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A—strengthening our brand for the future; Sigmund Freud—his oral neoplastic disease and oral, maxillary, and facial surgery; Sylwester Gogolewski; AO in Scotland; Davos Courses 2006—assessment and evaluation; AO Educators’ Seminar for ORP, Davos 2006—a week to remember; AO Principles of Fracture Management; AOSpine Manual; Implant surfaces: Do they have any relevance to the surgeon? Platelet-rich plasma for bone healing—to use or not to use?; Biotechnology in musculoskeletal surgery: outlook and expectations; Pelvic and acetabular fractures—past, present, and future; AO Debate—acute on chronic, unstable slipped capitalfemoral epiphysis
Citation preview
AODIALOGUE
AO Foundation
The magazine for the AO community 1 / 07
Community zone
AO—strengthening our brand for the futureNew corporate identity released April 2007
Expert zone
Implant surfaces: Do they have any relevance to the surgeon?Research within AO
2 AODIALOGUE 1 | 07
Table of contents
community zone
AO in depth
4 AO—strengthening our brand for the future
people
6 Sigmund Freud—his oral neoplastic disease and oral, maxillary, and facial surgery 10 Sylwester Gogolewski
events
11 AO in Scotland12 Davos Courses 2006—assessment and evaluation15 AO Educators’ Seminar for ORP, Davos 2006—a week to remember
news
18 AO Principles of Fracture Management19 AOSpine Manual
expert zone
20 Implant surfaces: Do they have any relevance to the surgeon?
25 Platelet-rich plasma for bone healing—to use or not to use?
30 Biotechnology in musculoskeletal surgery: outlook and expectations
36 Pelvic and acetabular fractures—past, present, and future
40 AO Debate—acute on chronic, unstable slipped capital femoral epiphysis
AO Dialogue May 2007 Editor-in-Chief: James F KellamEditorial Advisory Board:Jorge E AlonsoJames HunterFrankie LeungJoachim PreinJaime QuinteroPol M RommensPublisher: AO FoundationDesign and typesetting: nougat.chPrinted by Bruhin Druck AG, Switzerland
Editorial contact address: AO FoundationStettbachstrasse 6CH-8600 DübendorfPhone: +41(0)44 200 24 80Fax: +41(0)44 200 24 60E-mail: [email protected] © 2007AO Foundation, Switzerland
All rights reserved. Any reproduction, whole or in part, without the publisher’s written consent is prohibited. Great care has been taken to maintain the accuracy of the information contained in this publication. However, the publisher, and/or the distributor and/or the editors, and/or the authors cannot be held responsible for errors or any consequences arising from the use of the infor-mation contained in this publication. Some of the prod-ucts, names, instruments, treatments, logos, designs, etc. referred to in this publication are also protected by patents and trademarks or by other intellectual property protection laws (eg, “AO”, “TRIANGLE/GLOBE Logo” are registered trademarks) even though specific reference to this fact is not always made in the text. Therefore, the appearance of a name, instrument, etc. without designa-tion as proprietary is not to be construed as a representa-tion by the publisher that is in the public domain.
Research within AO.
Read more in the expert zone.
AODIALOGUE
3
the AO Foundation. Without a policy or
program in communications, we lack
the ability to meet the needs of our in-
dividuals and stakeholders who are in-
volved with the Foundation, which is
you, our readers and you, our course
participants. We also lack the ability to
promote ourselves throughout the world
as an independent academic surgical re-
search and education foundation. Mr
Daemon has an impressive background
in communication and most important-
ly has a philosophy of communication
that matches the vision and mission of
the Foundation. As Editor of AO Dia-
logue and the head of the AO Commu-
nications Advisory Board, I wish to wel-
come him aboard and look forward to
the changes he will bring us.
Finally, in the expert zone there are sev-
eral articles by our research scientists.
These individuals, Mauro Alini, Geoff
Richards, and one of our biotechnol-
ogy advisors from the AO Biotechnol-
ogy Advisory Board, David Grainger,
are bringing forth changes in how we
approach fracture fixation and fracture
healing. Mauro Alini reviews platelet
derived growth factors and their effect
on bone healing. Geoff Richards shows
how changes in implant surfaces can
modify how the body reacts to the im-
plant. David Grainger provides an over-
view of the change that biomaterials
and biotechnology may have in our fu-
ture care of musculoskeletal injury and
disease.
Once again, although change strikes
fear and concern in our hearts, if done
well and for the appropriate reasons, it
can only make us better as it can for the
Foundation.
James F KellamEditor-in-Chief
editorial
Changes
We ask why someone has done this to
us. Life was satisfactory so why are you
doing this to me? However, we must
recognize that at times change is for the
better and necessary. This issue of the
AO Dialogue brings to our readers sev-
eral major advantageous changes with-
in the Foundation.
Firstly, the AO image is in the process of
change. All of you are very familiar with
the Blue Triangle and Yellow World that
form our logo. This logo has important
traditional and personal connections
to AO and to Davos so to change it has
many very important considerations for
the AO Foundation. Consequently it was
decided not to get rid of it completely but
to standardize it so that it will be recog-
nized worldwide and used in a standard
fashion. Our President, Christian Van
der Werken will outline the reasons for
this change and the importance of this
change for the AO Foundation.
Secondly, I would like to introduce you
to Herwig Daemon, our new head of
communications. Communications is
a new but very important area within
The mention of change always throws fear into most of our hearts. What we were comfortable with is about to be changed.
4 AODIALOGUE 1 | 07
• To modernize the overall AO brand commu-
nications appearance. In doing so, we portray
ourselves as a modern organization by slight-
ly updating the earlier designs. The AO logo
will be modified, with different logo versions
for different applications to accommodate a
variety of print technologies (Fig 1). We will
maintain our existing typography (Formata
and Meridien fonts) for familiarity. Our brand
colors of blue and yellow will be redefined to
strengthen the print quality, and we will use
secondary colors for charts, graphics, and a re-
definition of imagery and style (Fig 2).
• To simplify the complex AO brand structure
that currently exists. Today each institute,
region, and section has its own brand design.
(see Fig 3) As a single organization, we can
consolidate each of those institutes, regions
and sections to be recognized as “one AO”.
By simplifying our brand structure, we will
achieve one streamlined look for all organi-
zational units within AO and increase brand
recognition worldwide.
Put simply, Corporate Identity is the identity of
a corporation or organization which appears in
the form of a brand, trademark or logo—usually
created within a set of guidelines. These guide-
lines are crucial because they define how the
identity is applied for consistent use: through
colors, typefaces, layouts, logical “brand” hierar-
chy, and so on.
Strengthen, modernize, simplify, reduceThe efforts to create an updated, consistent Cor-
porate Identity for the AO are based on four main
goals:
• To strengthen the AO brand recognition as
well as our worldwide recognition. This is pos-
sibly the biggest challenge we face today. With
the impact of globalization, it is more crucial
than ever to present one face to the world. An
easily distinguishable identity also appeals
more to its target audience. The AO name and
logo are strong, and have been around long
enough to prove so. But an attractive logo is
not enough—for a brand to achieve recogni-
tion, it requires consistency in its use. And
that can only happen through having a clear
set of guidelines, and adhering to them.
Christian van der WerkenPresident of theAO Foundation
A Message from the President
AO—strengthening our brand for the future
At the start of April 2007, AO released its new Corporate Identity to the world. But what exactly is Corporate Identity, and why is it important?
5community zone AO in depth
• To reduce costs. A new “one-size-fits-all” con-
cept will involve a consolidation of formats,
including the development of a web-based
design tool for non-design professionals that
is easy to use. Our existing media will be re-
developed, with new stationery (DIN and US
formats), newsletters, notepads/forms, litera-
ture (brochures—from the annual report to
the course programs), presentations, posters,
and any other special formats.
Roll-out planEach AO employee involved in planning, creat-
ing, or implementing media will receive a set of
guidelines in the near future. I’m looking for-
ward to seeing the effects of this new initiative,
and am counting on each and every AO employ-
ee to help ensure that these guidelines will be
consistently carried out in order to make it a real
success.
For addtional information go to:www.aofoundation.org
Pantone© 294 C
CMYK 100/68/7/30
Pantone© 109 C
CMYK 0/10/100/0
Colors
Fig 1 The modifi ed AO logo.
Fig 2 The AO brand colors.
AO Foundation AO East Asia AO Austria
AO CMF
AO Alumni Association
AO Foundation Research
AO Latin America
AO Switzerland
AO Veterinary
AO ORP Alumni Association
AO Foundation Development
AO North America
AO Germany
AO Foundation TK System
AO Spain
AO Foundation Clinical Investigation
AO UK
AO Foundation Education
AO Foundation Publishing
AO Foundation Research Fund
Organization Regions Sections Specialties Alumni Associations
AO Alumni AssociationChapter Germany
AO Alumni AssociationChapter France
AO Alumni AssociationChapter USA
AO Alumni AssociationChapter Czech Republic
AO Alumni AssociationChapter Thailand
and more
Sender address structure
Fig 3 The modifi ed AO address “tree“.
6 AODIALOGUE 1 | 07
Sigmund Freud (1856–1939), the
founder of psychoanalysis, devel-
oped a carcinoma of the buccal cav-
ity in 1923, which was treated be-
tween 1924 and 1938 by Prof Hans
Pichler (1877–1950), Professor of
Oral, Maxillary, and Facial Surgery
at the University of Vienna, Aus-
tria. Freud and Pichler were both
professors there.
Freud’s neoplastic disease illus-
trates the development of onco-
logical oral, maxillary, and facial
surgery from 1920–1940, and the
problems of maxillary resection. It
also shows the specialty’s medical
and technical developments which
occurred in that time period.
This chronicle takes place against
the backdrop of the National So-
cialist dictatorship in Germany and
Austria.
Detailed information on Freud’s neo-
plastic disease is available from two
sources. The first is Pichler’s 80-page
closely-written case history report,
and the second is Freud’s 1929–1939
diary, in which he recorded percep-
tions about his own health.
The first consultation with Pichler
in 1919 was occasioned by painful
Prof Nicolas HardtClinic for Oral, Maxillary and Facial Surgery, Cantonal Hospital, Lucerne, Switzerland
swelling in the area of the right pal-
ate and maxillary tuberosity which
had lasted for about a week.
In 1920, an ulcer developed in the
same area of the tuberosity, which
healed by itself.
Despite being forbidden to smoke,
Freud continued to smoke 20 cigars
daily. In February 1923, the re-
newed occurrence of erosion in the
area of the right posterior alveolar
tuberosity was diagnosed by his
treating internist Dr Felix Deutsch
as leucoplakia with dysplasia. He
was referred to Prof Markus Hayek
(1861–1941), Head of the Ear, Nose,
and Throat clinic in Vienna.
Prof Hajek undertook a partial local
excision in the area of the right
tuberosity under local anesthesia.
Postoperation, significant arterial
bleeding was stemmed by the at-
tending nurse.
The histopathological examination
showed the presence of a squamous
cell carcinoma. Freud was not in-
formed of this, and he was referred
to Prof Guido Holzknecht (1872–
1931), who applied radiotherapy.
In September 1923, during a jour-
ney to Rome, Italy, Freud suffered
Sigmund Freud
His oral neoplastic disease
and oral, maxillary,
and facial surgery
1 Sigmund Freud at different times in his life.
1909 1923 1930
1931 1935 1938 1939
1914
7community zone people
tions between 1926 and 1928, each
comprising local excisions and dia-
thermy treatment. In March 1928,
a fifth new obturator prosthesis was
inserted.
By 1929 Freud had lost confidence
in Dr Deutsch, and Dr Max Schur
(1897–1969) took over the follow-
up visits as his personal physician–
a total of 49 consultations. Pichler
performed no new treatments from
June 1928 to 1929.
In 1929, political unrest first be-
came apparent with the raids of
Nazi groups on Prof Tandler’s Ana-
tomical Institute, forcing students
to flee through windows.
In the fall of 1929, Freud traveled
to Berlin for the new construction
of obturator prostheses by Prof Her-
mann Schröder—an oral surgeon
at the Charité University Hospital.
In October 1930 there was a clear
recurrence at the operation site,
leading to an eleventh operation by
Pichler with further resection, split
skin transplantation from the fore-
arm, and a renewed intraoperative
insertion of an obturator prosthe-
sis. The histopathological findings
showed precancerous changes.
More relapses occurred in February
and April 1931. These relapses were
treated by means of electrocoagu-
lation, which had been introduced
into surgery in 1930 by Hans von
Seemen, a pupil of Erich Lexer.
The recurrence in April 1931 was
excised during an additional sur-
gical intervention under local an-
esthesia. This resulted in major
arterial bleeding, and the resected
area was covered with a split skin
graft. The histopathological results
from a major oral hemorrhage,
which stopped without treatment.
Once home, he consulted Pichler,
who recorded the findings shown
in figure 3. Tumor growth was con-
firmed in the area of the tuberosity,
palatoglossal arch, and palate, with
involvement of the cheek and man-
dible.
On October 4, 1923, assisted by
Bleichsteiner, Pichler performed
a ligation of the right external ca-
rotid artery, with extirpation of the
submandibular and cervical lymph
nodes.
In a follow-up operation one week
later, a partial maxillary resection
was performed. Covering of the
wound surfaces was carried out
using the split skin graft technique
published in 1917 by Esser (1877–
1976), and by the insertion of a pro-
visional obturator prosthesis. On
the evening of the operation, Freud
enjoyed two Havana cigars.
Based on the histopathological re-
sults (R1 resection), Pichler, as-
sisted by Hofer and Bleichsteiner,
performed a fourth operation on
November 12, 1923, which com-
prised further resection of the pter-
ygoid process and a partial resec-
tion of the soft palate.
During 1923 and 1924, there were
a total of 143 outpatient consulta-
tions with Pichler. Three new obtu-
rator prostheses were made in this
time period.
Between 1926 and 1936 there was
a cycle of continually relapsing leu-
coplakia, nonspecific proliferations,
precancerous changes, and papillo-
mas. This led to 122 consultations
and 5 further operative interven-
again showed
the presence of
a precancerous
lesion.
Freud turned
to Prof V Kan-
zanjian (1879–
1974) to con-
struct three
new prostheses
in Hans Pichler’s laboratory. One
was made of hard rubber, and two
from hard rubber with a palate sec-
tion made of soft rubber. The cost
of these prostheses was US $6,000,
and paid for Boston based Kanzan-
jian‘s European vacation.
Freud’s acceptance of prostheses
was extremely bad, he called them,
“the curse of my life”.
In 1932, four operations with exci-
sions and electrocoagulations were
performed for multiple recurrenc-
es. The histopathological diagnosis
of cancer in situ continued to be
made.
When the Nazis took power on Jan-
uary 30, 1933, Germany not only
experienced political changes, but
also a power takeover of its clin-
ics. Under an April 1933 law, po-
litically unreliable professors were
dismissed from public office (a total
of about 15%, up to 30% in Berlin
and Frankfurt). Racism played a
decisive role in only a third of the
professors dismissed (Evans 2000).
This affected 11.5% of all internists,
10% of surgeons, 17% of neurolo-
gists, 90% of psychoanalysts and
5% of oral surgeons. At the Charité
in Berlin, every third doctor was dis-
missed (Bleker and Jachertz 1989).
Prof Cohn-Stock (1891–1985), who
2 3 4 5
2 Prof Markus Hajek (1861–1941).3 Findings at the consultation with Prof
Pichler in 1923.4 Prof Hans Pichler, 1923.5 Dr Max Schur (1897–1969).
Freud’s acceptance of prostheses was extremely bad, he called them, “the curse of my life”.
8 AODIALOGUE 1 | 07
movement, as the Austrians will
not become as brutal as the Ger-
mans”.
A classical failure of judgment, as
resulting events would show.
June 6, 1933: “The world is a huge
prison and Germany is the worst
cell. It pleases me to think that we
are still living as if on an island of
the blessed”.
Freud must have known that the
elite of German psychiatry pas-
sionately supported the Nazis’ laws.
For example, the neurologist and
psychiatrist Prof Carl Bonhoeffer,
while explicitly against killing by
doctors, nevertheless did not con-
demn the inhuman practice of ster-
ilization (Kater 2002).
In 1934, on the recommendation of
Prof Rigeaud of the Institut Curie
(Paris) and Prof Schloss (Vienna),
a radium prosthesis was inserted.
No further details exist. Further re-
lapses occurred, resulting in three
local operative interventions in
May, June, and September 1934.
The first signs of political chaos in
Austria began with the murder of
the Federal Chancellor, Dollfus, by
Austrian Nazis on July 25, 1934.
Freud’s health continued to suffer.
In 1935 four operations were per-
formed with the diagnoses: verru-
cous leucoplakia, papilloma, and
precancerous papilloma.
In January and March of 1936, the
26th and 27th operations were per-
formed, with the same histopatho-
logical findings of verrucous leuco-
plakia. In July the 28th operation,
the first to be performed not under
local anesthesia, but using nitrous
performed the first maxillary seg-
ment osteotomy in 1920, was one of
many who then emigrated.
At the notorious book burning at
the University of Berlin on May 10,
1933, Freud was declaimed with
the sentence: “against the overesti-
mation of life’s psychological drives
which eat away at the soul, and for
the nobility of the human spirit. We
surrender the written works of the
Jew S Freud…”
Compared to the lot of German
Jews, Freud considered life in Aus-
tria to be like living on an island
of the “blessed”. He was under the
false impression that anti-Semitism
would not find fertile soil in Aus-
tria.
Freud in January 1933: “People are
afraid that the German nationalis-
tic excesses are going to encroach
on our little
country. That
is nonsense. I
do not see any
danger here”.
April 8, 1933: “If
the Nazi move-
ment extends
to Austria, its
course will not
be marked by
the excesses of
the German
oxide anesthesia and local anesthe-
sia, with the resection of an ulcer in
the area of the palate took place.
The histopathological diagnosis
showed the presence of a squamous
cell carcinoma, 13 years after the
first diagnosis. As there were no
tumor-free areas in the contours, a
29th operation was performed with
follow-up resection, and again in
December, another operation under
nitrous oxide anesthesia, with co-
agulation of a new ulcer.
An extreme trismus followed, for
which newly discovered short wave
treatment was applied.
The 31st operation was performed
in April 1937, and no new tumor
growth was found. The extreme
trismus and pain remained; the
maximal mouth opening was mea-
sured as 12mm distance between
incisor teeth.
The pathologist Prof Erdheim, who
had provided almost all the previ-
ous histological diagnoses, died at
the end of 1937. So great was his in-
volvement in this case that he was
able to identify unlabeled sections
as belonging to Freud.
In January 1938, a squamous cell
carcinoma again recurred in the
areas of the maxillary antrum and
orbital floor, leading to a 32nd op-
eration under nitrous oxide anes-
thesia with extensive resection of
these regions.
A follow-up resection performed in
February showed only leucoplakia.
In March 1938, the Nazis assumed
control of Austria. Freud described
this as FINIS AUSTRIAE, by which
he was referring more to the demise
116 7 8 9
6 Prof Hermann Schröder of the Berlin Charité.
7 Prof Jakob Erdheim (1874–1937).
8 Prof V Kanzanjian (1879–1974).
9 Obturator prosthesis with detachable palate section.
10 Prof Günther Cohn-Stock (1891–1985) Charité Berlin.
11 May 10, 1933: Burning of books.
10
“People are afraid
that the German
nationalistic excesses
are going to encroach
on our little country.
That is nonsense.
I do not see any
danger here.”
9community zone people
During an examination in London
in July 1938, Dr Exner, a South Af-
rican oral surgeon who had previ-
ously been a guest of Pichler, could
also find no tumor; although Schur
was convinced that a recurrence of
the tumor would occur.
Pichler flew to London on Septem-
ber 7, 1938, and his examination
showed an extensive recurrence of
the carcinoma with extension to
the right orbital floor. Surgery took
place on September 9, 1938, using
the McIntosh intubation technique
that had not yet been introduced to
continental Europe. A cheek flap,
using the method of Moure (1922),
was performed and an extensive
right-sided resection of the maxilla
and orbital floor with concomitant
intraoperative instantaneous sec-
tion monitoring. This was also not
in use on the Continent.
The diagnosis using instantaneous
sections showed an R0 resection,
ie, tumor-free resection edges with
the histopathological diagnosis of a
verrucous leucoplakia. A renewed
tumor growth in the orbital floor
area occurred in February 1939.
The sample excision confirmed the
presence of a squamous cell carci-
noma. Prof W Trotter and Exner
described the tumor as inoperable.
Pichler wrote to insist on an addi-
tional operative intervention.
On the advice of the treating doc-
tors, x-ray irradiation was per-
formed by the radio-oncologist Dr
Finzi.
As was to be expected, a necrosis
with perforation occurred in the
area of the right cheek, which led
of the upper middle class of the old
Austria than to political change.
Austria’s absorption into the Third
Reich marked the beginning of
Jewish persecution, and thus of
Freud. Using the 1935 Nuremberg
racial laws, 28 professors and 120
university lecturers were dismissed
from public office.
Austrian Nazis enthusiastically as-
sisted the German anti-Semites.
This was based on a racism that
had a stronger tradition and deeper
roots in Austria and Hungary than
in Germany (Carsten 1976, Kater
2002). By the spring of 1939, almost
2,000 Jewish doctors in Austria
were forced to give up their profes-
sion.
In spite of his neoplastic disease,
Freud, then 82, decided to emi-
grate but was unable to obtain an
exit permit, as the Nazis already re-
garded Freud as the personification
of the Jewish enemy.
Faced with this situation, Pichler
managed to convince Dr Sauer-
wald—the party commissioner
responsible for exit permits—that
Freud’s scientific works were not
concerned with “Jewish villanies”,
and he succeeded in getting Sauer-
wald to study Freud’s writings.
Sauerwald then suppressed all in-
criminatory documentary evidence
against Freud, while Pichler dealt
with the secret police. Freud left Vi-
enna on the Orient Express on June
4, 1938.
Before departure, a last examina-
tion was carried out by Pichler on
June 2, 1938, who detected no re-
currence of the tumor.
to unbearable pain. In one of his
last letters, Freud wrote on July 5,
1939: “My world is a small island of
pain floating on an ocean of indif-
ference.“
Sigmund Freud fell into a coma on
September 21 and died at 3am on
September 23, 1939.
SummaryProf Pichler’s treatment of the 14
year long neoplastic disease en-
abled Freud to create his impressive
later works. Thanks to the skilful
intervention of Pichler, Freud was
able to leave Austria for Britain and
thereby avoid the fate of many of
his compatriots.
Max Schur, the doctor and poet,
wrote the following in 1972 about
Prof Pichler: ”He was an exception-
ally kind-hearted and human per-
son. A surgeon who was not afraid
of performing radical interventions
when they were necessary. His as-
sociation with Sigmund Freud was
one of extreme respect, tact, and
politeness. Pichler was fortunately
a man of obsession, in the best spir-
itual meaning of the word.”
BibliographyLiterature in the author’s
possession.
12 13 14 15
12 Prof Hans Pichler 1936.
13 Nitrous oxide anesthesia 1936 Munich University.
14 Pogrom in Vienna 1938.
15 Departure on the Orient Express Vienna-Paris-London. Princess Marie Bonaparte, American ambassador Bulitt.
16 Insuffl ation anaesthesia 1940 using the method of McIntosh.
16
10 AODIALOGUE 1 | 07
During his time within the AO organization,
he first studied polylactides as candidates to
replace internal fixation devices. He soon real-
ized that constructs made of this material may
also serve as bone substitute materials, and that
membranes and scaffolds were most valuable for
tissue engineering purposes. In great detail, he
investigated and developed different composi-
tion, manufacturing, and sterilization processes
to make sure the materials fulfilled their func-
tion in the human body. In later years in Davos,
his attention turned again to polyurethanes,
another bioresorbable material, which can be
tuned to provide optimal conditions for bone as
well as cartilage tissue engineering. He not only
conducted excellent research, but had his own
and his team’s work published in renowned,
peer reviewed journals. No less than 150 pub-
lications were the result of his tireless work and
maybe twice as many abstracts were presented
in the leading orthopedic and biomaterials meet-
ings. He was active right up until the end of his
career at the AO. Indeed, two of his final proj-
ects on isosorbide-based biodegrad-
able polyurethanes and the use of
various plant polyprenols to biolize
biodegradable polymeric scaffolds
to promote cell attachment, growth
and proliferation, and/or to prevent
tissue adhesion may yet yield great
rewards.
Prof Gogolewski provided his ex-
cellent knowledge of the chemistry,
synthesis, and production of resorb-
able biomaterials as well as their
behavior in the human body freely
to everyone interested in this sub-
ject. This knowledge allowed him
to realistically assess the potential
of a future treatment option. He
has been a cornerstone of the AO
Research Institute for 18 years and
contributed greatly to our expertise
in this area. I sincerely thank him
for his innovative work and tireless
dedication and wish him a long and
happy retirement.
Erich SchneiderDirector AO Research Institute
Professor Sylwester Gogolewski is a well-known
figure to many within the AO. He has worked
on bioresorbable polymers in the AO Research
Institute for the past 18 years. After a long ca-
reer spent mostly in the world of research, this
knowledgeable man whose vim and vigor belies
his age, has left Davos and the AO to return to his
home country.
Sylwester was born in 1936 in Warsaw, Poland.
He received his Master’s Degree from the Uni-
versity of Lodz, where he specialized in chemis-
try. His doctoral dissertation dealt with nylon, a
modern polymer at that time and his habilitation
with the crystallization of polyamides. Moving
up in his academic career, he became Associate
Professor and Head of the Polymer Department
at the Technical University of Zielona Góra. 1980
was the year he made Western Europe his per-
manent home and became a Visiting Professor
at the Department of Polymer Chemistry in the
University of Groningen, the Netherlands. Even
though he only stayed there for three years, his
work on vascular prostheses and
polyurethanes carried out in this
institution inspired him again and
again throughout the years. In
August 1983 he decided to leave
the university to join a Swedish
research and development com-
pany in the French speaking part
of Switzerland. He joined the AO
Foundation in 1988 with the task of
researching and developing resorb-
able materials for use in fracture
treatment.
Sylwester Gogolewski
On his retirement, a tribute to his contributions to the AO.
11
AO in Scotland
Chris OliverConsultant Trauma Orthopaedic SurgeonEdinburgh Orthopaedic Trauma Unit
Edinburgh has a long and distinguished history
in medicine and surgery, with many advances
pioneered in the city or by Edinburgh graduates.
Notable surgeons include John Hunter, anato-
mist and “founder of scientific surgery“ in the
late 18th century; Robert Liston, who performed
the first operation under anesthesia (ether) in
1846; and Sir James Simpson, who discovered
chloroform the following year, by testing it on
his dinner guests until they slid under the table!
Other “firsts” include Charles Bell, who identi-
fied the nerve functions in 1811 and founded
the science of neurology; James Syme, pioneer
of plastic surgery; the first hypodermic syringe
(Alexander Wood 1853). In the early days,
anatomy students had difficulty obtaining suf-
ficient subjects for dissection, and the need was
filled by grave robbers—the “resurrectionists”.
In 1829 Messrs Burke and Hare streamlined the
process by murdering and then selling their vic-
tims directly to the unquestioning university‘s
surgical department. The pioneering trail con-
tinues through Alexander Fleming, discoverer of
penicillin (1928) and anti-typhoid vaccines, the
UK‘s first successful kidney transplant (Michael
Woodruff, 1960) and the cloning of the famous
Dolly the Sheep (Ian Wilmut, 1996).
The 4th Scottish AO Principles of Operative
Fracture Management Course for Surgeons was
held in March 2007 in Edinburgh. The four day
course was held at the new surgical skills centre,
Quincentenary Hall (www.surgeonshallcom-
plex.com) at the Royal College of Surgeons of
Edinburgh (www.rcsed.ac.uk). The Quincente-
nary Hall is a new state-of-the-art surgical skills
complex in a versatile modern building adjacent
to the historic Surgeons’ Hall. The course chair-
manship was taken over by Mr Clark Dreghorn
(Glasgow) and Mr Andy Kent (Inverness) this
year, replacing Mr Chris Oliver and Mr John Ke-
ating from the Edinburgh Orthopaedic Trauma
Unit who have led the course since its inception
in 2004. The faculty is mostly Scottish with sur-
geons from Edinburgh, Glasgow, Stirling, Pais-
ley, Aberdeen, and Inverness. On this occasion
Dr Maarten van der Elst came from the Neth-
erlands as visiting faculty. The course now ca-
ters for 48 participants of which half come from
Scotland. The AO Principles Course in Scotland
has not only allowed the participants to develop
skills but has also allowed the Scottish surgeons
to become a cohesive force in trauma orthopedic
surgery. The high standard of the Scottish train-
ing workshops, lectures, and discussion groups
has been internationally recognized.
community zone events
12 AODIALOGUE 1 | 07
Davos Courses 2006
Assessment and evaluation Piet de BoerDirector AO EducationDübendorf, Switzerland
Assessment of a course and evaluation of indi-
vidual presentations within that course is a com-
plex and controversial area. Everyone is agreed
that the purpose of AO Education is to improve
the quality of care given to patients by the course
participants after the course. We are probably
several decades away from being able to measure
this effect, but the Davos Courses in 2006 were a
landmark in our progress towards this goal.
Davos 2006 saw two new programs rolled out for
the first time—needs assessment and the Audi-
ence Response System (ARS) based course eval-
uation system.
Needs assessment This is the brainchild of Bob Fox and Joe Green,
our US based educational consultants. The proj-
ect began following an AOEB brainstorming re-
treat at the triennial Alumni event in Sardinia
in 2005. Individual course chairmen around
the world were asked to define key competen-
cies for the courses that they were running. A
competence is something that you wish the
course participants to acquire as a result of the
course. Twelve competencies were defined for
the Principles course and twelve for the Advanc-
es course. For the principles course, a different
group of course chairmen were asked to write a
series of questions with yes/no answers, relating
to the competencies that had been defined, to be
able to assess the knowledge level of the course
participants before the course began.
Course participants were contacted online some
four weeks before the course and asked to look at
the competencies that had been defined for their
course. They were asked to evaluate how impor-
tant each of these competencies were on a scale
of 1–5 and to record how well they thought they
already understood these competencies. The dif-
ference between the two scores reflected a mea-
sure of how motivated the course participants
were. Clearly if a course participant has a high
perceived need for a given competence and thinks
that he has a low level of current knowledge then
that course participant will be extremely moti-
vated to learn. Following completion of this per-
ceived needs assessment, course participants on
the Principles course were then asked a series of
13community zone events
The significance of these results is two fold.
Firstly, we have shown that this system can be
made to operate reliably and provide reproduc-
ible results. Secondly, because AO now possesses
and uses such a system we can truly say to any
CME authority that the contents of our courses
are determined by the needs assessment of our
course participants—the highest level of quality
as dictated by the CME regulating authorities.
Furthermore, the results with regards to the per-
ceived needs of our course participants will help
determine the future structure of courses.
Audience Response System ARS based course evaluation of individual pre-
sentations was carried out on all AO courses this
year. Course chairmen were asked to define five
key learning objectives for their courses. Course
participants were asked at the start of the course
how important these were to their everyday
practice. At the end of the course, course partici-
pants were asked about these key learning objec-
tives. They had five choices:
1. Did not learn anything new.
2. Learned something new, but do not want to
use it in my practice.
3. Learned something new, but probably won’t
be able to use it in my practice.
4. Reconfirmed that what I do in my practice set-
ting is appropriate.
5. Learned something new and plan on using it
in my practice
It can be seen that answers 4 and 5 represent a very
positive learning experience from the course.
yes/no questions relat-
ing to the individual
competencies. Analy-
sis of these results gave
an understanding as
to the current level
of knowledge of the
course participants.
Following the course,
the course partici-
pants were asked to
fill in the same needs
evaluation form and to
complete a set of ques-
tions relating to the
competency.
ResultsThe results of the per-
ceived needs of the
course participants from Davos closely reflected
those of course participants in Leeds, Sapporo,
Reno, San Diego, Stockholm, and Dubai. Over-
all, course participants were extremely highly
motivated and it is interesting that they rated
the importance of the individual competencies
quite consistently. The need to assess and treat
a haemodynamically unstable pelvic fracture in
an emergency situation was rated by all course
participants, outside Japan, as being the most
important skill they could acquire from the Prin-
ciples course.
Assessment of the yes/no questions showed that
approximately 60% of the course participants
got the question right and 40% wrong. This re-
flects the relatively junior nature of our Princi-
ples course participants in Davos and this data
is similar to that collected in Leeds and in Uru-
guay.
Following the course, the perceived needs of the
course participants dropped dramatically. That is
to say that the course participants assessment of
the course was extremely favorable. Disturbing-
ly, the results from the yes/no answers however
showed virtually no change. We are, at present,
working with colleagues from AO North Ameri-
ca to change the knowledge assessment tool to a
more sophisticated system, to try to better assess
the true level of knowledge of our course par-
ticipants.
Perceived needs—participants fill in:
D Desired level of competence (1–5)
P Present level of competence (1–5)
How to read gap values:
≥ 3 Fear
1.6–2.9 High interest & motivation
≤ 1.5 Low interest & motivation
14 AODIALOGUE 1 | 07
At the end of each lecture, discussion group,
and practical course, participants were asked to
evaluate the presentation. They were asked to
evaluate the presentation on a scale of 1–5, as to
whether the presentation had been relevant to
their practice. They were then asked to evaluate
the performance of the individual faculty mem-
ber concerned in the presentation.
ResultsThe results with regards to the five key learning
points for the courses showed that most courses
had been overwhelmingly successful in achiev-
ing their learning objectives. Particularly suc-
cessful courses were the Swiss Residents’ course
held the first week in Davos and the English
Principles course held in the second week.
Most courses were extremely well rated by the
course participants. However, comparison of the
individual courses did show that some courses
were consistently more successful than oth-
ers with regards to the course participants’ as-
sessment. This information was fed back to the
course chairmen and individual faculty mem-
bers and will form a basis for the reevaluation of
individual courses in the future.
The data with regards to the in-
dividual presentations revealed a
hitherto unknown fact. If an in-
dividual presentation was rated by
the course participants as not being
relevant to their practice, then the
course participants almost invari-
ably rated the performance of an
individual faculty member as being
poor. The correlation between
these two figures, which has never
been recorded before in education
research literature, will form the
basis for further studies.
Individual faculty were given infor-
mation with regards to their own
particular performance, but were
not given information about others.
The assessment of their own per-
formance could be gauged by their performance
scores and also by the difference in the scores be-
tween the relevance scores and the performance
scores. In the future, we hope to be able to ana-
lyze conspicuously good or less than average per-
formance and provide advice to the individual
faculty member as to how to improve their own
performance.
Overall, the amount of information that we have
gained about the Davos 2006 Courses is huge.
Well over a quarter of a million pieces of infor-
mation were collected and evaluated and the re-
sults give us the most comprehensive view of the
success of Davos in 2006. This program will con-
tinue in the years to come and allow us to get an
understanding of how things are changing and
hopefully improving with the years. Individual
course chairmen now get useful information
with regards to planning of future courses and
individual faculty members get, for the first time,
an objective assessment of their own particular
performance. Future developments will include
the refining of the question and answer section
of the needs assessment and an introduction of
this into the Advances courses. We hope that in
2007 a more detailed needs assessment will be
able to be carried out for certain other courses
including the orthopedic geriatric course.
The next development in assessment will be the
introduction of a research project entitled “The
Barriers Project”. The barriers project attempts
to look at the barriers that exist for surgeons
who wish to change their practice but are not
able to do so. A pilot project carried out in 2005
revealed that over 75% of the Advances course
participants were unable to change their prac-
tice—even if they wanted to—the most common
reason being an inability to access or afford the
equipment. This research project was approved
by the AOEB at its March meeting and prelimi-
nary results should be available in early 2008.
The barriers project takes us another small step
towards the end process of evaluation of our ed-
ucational events—evidence that we change the
practice of surgeons so as to improve the results
of patient care.
15
A week to rememberAO Educators’ Seminar for ORP, Davos 2006
Yvonne MurphyRegistered NurseBirmingham, United Kingdom
A group of 22 ORP educators from England,
USA, Australia, New Zealand, Austria, France,
Germany, Belgium, Norway, Sweden, Switzer-
land, Mexico, Brazil, Israel, Iran, Malawi, and
China gathered at the 6th ORP Educators’ Semi-
nar, in Davos, in December 2006 for an advanced
learning experience. The seminar’s aims were to
support the ORP in acquiring and developing ed-
ucational skills in order to contribute effectively
to the AO education program within their coun-
try and worldwide and to extend and develop
the AO ORP Alumni community. Faculty mem-
bers for this seminar included Susanne Bäuerle,
Rossanna Fornazzari, Lisa Hadfield-Law, David
Pitts, Donna Russell-Larson, and Isabel Van Rie.
Most of the course participants arrived on Sat-
urday, December 9, and stayed in the same hotel
allowing everyone to meet and bond almost
instantly. The first meeting of the participants
occurred at the hotel dining room where one
long table was reserved for the ORP. Participants
introduced themselves as they arrived and every-
one felt very welcome and comfortable. This was
the start of a group friendship that went from
strength to strength.
The course began early Sunday morning as the
group met at the hotel reception and were intro-
duced to some of the course core faculty. The wel-
come meeting for the entire surgical faculty was
held at the conference centre. I was astounded
at how many faculty members it took to run the
courses in Davos. The room was enormous and
almost full. The President of the AO Foundation,
Chris van der Werken, welcomed everyone with
an inspiring talk as did Piet de Boer, the Director
of AO Education.
community zone events
16 AODIALOGUE 1 | 07
Our group’s first task was to observe
the Principles precourse meeting.
We were asked to identify three
items we had learned from this ob-
servation. Although we all could
certainly identify more than three
items that we could use in our own
precourse meetings, it was evident
that a clear course plan of action,
review of the practical exercises,
and the opportunity for faculty to
discuss their concerns were the
most important items. Our group
was made to feel very welcome by
the surgical faculty and we were
encouraged to introduce ourselves
alongside our colleagues.
After the precourse meeting, the
group separated to do different
things including lunch, going back
to the hotel to rest etc. I was in a
group of five that chose to attend
the Synthes welcome get-together
on Jakobshorn Mountain. This was
an amazing experience for me as I
had never skied or been on a snow
covered mountain before. The trip
up the mountain made me a little
nervous when I realized how high
up we were going, but once there
I wouldn’t have missed it for any-
thing. The sun was shining yet it was snowing
and the snow looked like glitter falling from the
sky. In the midst of this there was a barbeque,
music playing, and mulled wine to keep out the
cold. It was a fantastic atmosphere and just one of
the many wonderful memories I will take from
Davos and keep with me always.
In the evening we returned to the conference
centre for the main welcome reception. After
the welcome we attended a dinner to meet the
course directors and core faculty who would be
facilitating the ORP educators’ seminar. This
was another great learning experience. Every-
one shared stories about their countries and how
courses for ORP were organized in each one, as
well as generally getting to know each other.
This was the first of many dinners together.
Monday was the first day of our seminar. The
president of the AO Foundation spoke about
the importance and value of ORP in AO educa-
tion. Following this, we went on to examine the
reasons we had come to the educators’ seminar.
Typical answers to this question included, “Be
able to give presentations and feel confident in
doing this”, “Develop my teaching skills”, “To
gain knowledge and ideas to take back to my
own courses”, “Share ideas and meet people”. We
heard a talk about valuing our differences. The
ORP faculty who travel to present courses in dif-
ferent countries spoke to us about the different
cultures and how doing and saying something
one way in one country may not be acceptable in
another, and how this needed to be recognized
and overcome in order to deliver a good course
for participants.
After observing a practical exercise involving
surgeons we were asked to identify three items
that had gone wrong. It was a fantastic learning
experience for our group. We went away with
the knowledge of what can go wrong even with
the best planning and realized how important
singing from the same song sheet is. I also think
the course director learned from us that day as
I know the constructive feedback was available
for him to see.
Finally we learned about presentations, the one
area where everyone seems to lack confidence.
We learned that “Proper preparation and prac-
tice prevents poor performance”. This includes
set, dialogue, and closure, and keeping slides
clear, concise, and simple. We also learned to in-
tegrate questions to make it interesting and to
ensure that the participants are awake!
Tuesday was another full and exciting day about
teaching and practicals. Developing the roles of
a table demonstrator and practical moderator
require guidance and support, and this seminar
was the ideal place to get it. After preparing and
running a practical, feedback was then given to
us by our observing faculty.
The day did not finish until late into the evening,
as we had been given the task of preparing a pre-
sentation for the following day on what we had
learned so far. It was a particularly difficult task
for my friends who did not have English as their
first language. However, it brought the whole
group together even more and created a strong
bond between us. Everyone helped each other in
Participants enjoying both the Davos weather and the seminar.
17community zone events
whatever way they could. It was hard work but
extremely rewarding.
Wednesday was “the performance”. This was a
day full of anxiety for us all, even though we
knew we were presenting to our friends. Need-
less to say it was a successful day full of emo-
tion as we all wanted everyone to do well. Those
without English as a first language did particu-
larly well. I am English and I understood every
presentation as they were all superb. The presen-
tations were videotaped and we have a copy to
look back on and learn from. The seminar from
this moment on seemed much more relaxed for
all of us as we felt that we had dealt with our big-
gest challenge, although the hard work and long
days continued.
The day finished with us learning about manag-
ing a discussion group. This type of learning I
particularly enjoy as I find talking to different
people easy. Others in the group found it more
difficult as it was not a familiar environment for
them and one not commonly used in their coun-
try. It was, however, something everyone wanted
to try once they had learned the principles.
At the end of the day we had a wonderful course
dinner where we were taken by horse and sleigh
up a mountain to a traditional Swiss restaurant
and ate to our hearts’ content.
On Thursday we found out about the AO Founda-
tion and how it works. We were informed about
the ORP Alumni and this now made sense to us,
we could see what an excellent group this was
for ORP education. We explored the AO website.
Exploring this was another wonderful learning
experience. I don’t think any of the group real-
ized how much information could be accessed
via this and we were all really enthused.
On Friday, we made the link between the re-
search lab and the patient. The process that the
products have to go through before approval is
quite daunting and extremely interesting. It
made me appreciate why implants cost as much
as they do. We were also given a practical to do
as participants. This was a really exciting ex-
perience for me as it was a tibial nailing and I
specialize in maxillofacial. With the experience
came the realization that teaching and learning
principles are just the same whatever the size of
the implant.
Finally the seminar came to an end and we re-
flected on what we had learned and what we
would do with it. We had all learned a great
deal and knew we had a lot to offer our home
countries. On my return home I made a list of
words that summed up this seminar for me: in-
spiring, excellent, interesting, networking, col-
laboration, realization, development, education,
encouragement, humor, laughter, and above all,
friendship.
The seminar topics inspire discussion.
18 AODIALOGUE 1 | 07
Volume 1 focuses on the basic knowledge and
the principles of fracture management, eg, bio-
mechanics, tools for preoperative planning, soft-
tissue management, different methods of reduc-
tion and fixation, implants. Simultaneously, it
addresses new issues pertaining to internal/ex-
ternal fixation, damage-control surgery, mini-
mally invasive surgery, and biotechnology.
Volume 2 focuses on the management of specific
fractures in different anatomical areas. For each
of these areas there is a separate chapter discuss-
ing the assessment of injuries, surgical anatomy,
preoperative planning, surgical treatment, and
postoperative care, while pointing out pitfalls
and complications. New fixation techniques and
implants have in particular been taken into ac-
count.
DVD-ROM for PC and Macintosh• All illustrations are available for download
and can be used for personal presentations.
• Animations and video clips featuring step-by-
step procedures can also be downloaded for
self-education or use within personal presen-
tations.
• The complete text of the book is available for
quick reference.
For more than forty years, the AO has—true to
its calling—imparted the principles of fracture
management by several publications and special
courses worldwide. The second edition of the AO
Principles of Fracture Management book has
been fully updated and extended to describe the
latest techniques and covers the complete con-
tent of the AO Principles Course of today. It is
now published as a two-volume set and provides
excellent guidance and expertise, compiled by
nearly one hundred contributors, all of whom
are renowned surgeons and members of the AO
faculty. An exceptionally large number of new
illustrations as well as animations and video
clips turn this work not only into excellent ref-
erence books but make them unique learning
tools. Both residents as well as advanced trauma
surgeons will benefit from this concept.
AO Principles of Fracture
ManagementSecond expanded edition
Thomas P Rüedi, Richard E Buckley, Christopher G Moran
AO principles
• Fracture reduction and fixation to restore anatomical relationships.
• Fracture fixation providing absolute or relative stability, as required by the “personality” of the fracture, the patient, and the injury.
• Preservation of the blood supply to soft tissues and bone by gentle reduction techniques and careful handling.
• Early and safe mobilization and rehabilitation of the injured part and the patient as a whole.
For addtional information and to order go to:www.aopublishing.com
19community zone news
AOSpine ManualPrinciples and techniques (Vol 1)
Clinical applications (Vol 2)
Max Aebi, Vincent Arlet, John K Webb
Clinical applications (Vol 2) is based on the novel
interactive sessions within AOSpine courses and
acts as a huge resource of clinical cases with
which the readers’ current knowledge on how to
treat their patients can be expanded.
It presents discussions concerning typical clinical
cases. The reader is involved in the development
of the rationale of treatment, the indications, the
contraindications, the argumentation in favor
of a technique or against one, and the outcome.
Case examples are outlined with learning points
from more than 50 surgeons of which each is a
leader in their surgical field. Clips from AOSpine
live surgery videos enhance the learning experi-
ence.
Max Aebi, Vincent Arlet, and John K Webb are
the three editors-in-chief who oversaw the cre-
ation and publication of this book along with a
team from the AO. More than 80 authors con-
tributed to the manual and the twelve section
editors ensured high standards throughout.
The two volumes offer the reader a combined
total of 1,500 pages and over 3,000 figures. Also
included is one DVD-ROM for both volumes.
Principles and techniques (Vol 1) relates to the
teaching of basic surgical knowledge and surgi-
cal techniques at AOSpine courses and acts as a
foundation for the application of these principles
in clinical practice.
It presents basic scientific and technical prin-
ciples—it provides the reader with the scientific
background to understand spine surgery and it
teaches how to apply these surgical principles
using the instrumentation necessary in a step-
by-step manner with exceptional illustrations;
some critical steps are explained using sequences
from AOSpine teaching videos.
For addtional information and to order go to:www.aospine.org
20 AODIALOGUE 1 | 07
Implant surfaces:Do they have any relevance to the surgeon?
R Geoff Richards
What happens when an implant surface is placed into the body? When inserting a plate, nail, screw, cage, or any other
internal fracture fixation (IFF) device into the body, regard-
less of the material, the implant is coated almost immediately
(within seconds) with a proteinaceous film upon contact with
blood. The proteins come from the blood and provide a provi-
sional matrix for the cells to adhere to. The cells never see the
actual implant surface but this matrix which has adsorbed to
the surface. The surface can determine which proteins absorb
and the orientation of their attachment. Cell adhesion then
usually follows within minutes (fibroblasts and macrophages)
followed by either soft-tissue adhesion or matrix adhesion and
eventual mineralization.
The molecular events at the surface-body interface are con-
trolled by surface properties. In an example of a metal used in
IFF (Fig 1), the actual surface is not the metal but a continu-
ally changing oxide surface. Metal ions diffuse at different
rates into the oxide and oxygen diffuses from the oxide into
the bulk metal. Biological ions are incorporated onto the oxide
along with protein adsorption. The proteins undergo confor-
mational changes over time. All these processes are influ-
enced by: surface topography, greater texture exposes more
discontinuities for interaction with proteins; surface chemis-
try, determines types of intermolecular forces, governing in-
teraction with proteins; surface hydrophobicity, determines
which and how much proteins bind; surface heterogeneity
(nonuniformity), different domains interact differently with
proteins; and surface potential, influences the distribution of
ions in solution and interaction with proteins. The protein
size, charge, and stability affect both the rate of arrival to the
surface and interaction with it. Blood (which has more than
150 proteins) interacts with the surface with albumin being
the most concentrated, having a moderate size (66KD) domi-
nating initial interactions. Fibrinogen (340KD), which has a
lower concentration in the blood has a rate of arrival at least
one hundred times slower, but usually dominates the surface,
exchanging with the faster and weaker bound albumin due to
its greater affinity. This is a very simple view of protein inter-
actions with a surface, but gives an idea of the dynamics of the
biological interactions.
21expert zone
What happens at a soft tissue–implant surface interface? Internal fracture fixation (IFF) implant surface finishes vary
from electropolishing of stainless steel to microrough com-
mercially pure titanium (cpTi) and Titanium-6%Aluminium-
7%Niobium alloy (TAN). TAN is used in LISS plates, locking
screws, and nails and is often mistakenly referred to as tita-
nium by surgeons. In the context of soft tissue, represented in
vitro by fibroblasts, members of my group found rough verses
smooth titanium and steel does not significantly affect fibro-
blast cell adhesion or subsequent growth. Polished TAN also
promoted fibroblast cell adhesion and growth; however both
aspects were seriously compromised on microrough TAN.
Specific aspects of the TAN topography were implicated (rough
beta phase particles within the softer alpha phase matrix),
however, the contribution of its unique surface chemistry to
the cell behavior was unknown. The observation of lower ad-
hesion, spreading, and growth on the surface of standard mi-
crorough TAN necessitated the design of a series of experi-
ments to help distinguish between the effects of material and
those of topography. Coating the standard test materials with
a uniform chemistry provided a practical model to investigate
how surface chemistry and the various topographies interact
in their effect on cells. These experiments eventually drew to
the conclusion that behavioral cues for fibroblasts on metal
implant surfaces were generally confined to the influence of
surface topography over the cue of surface chemistry.
Soft tissues, which are more sensitive to differences in im-
planted materials than bone, can react much quicker to prob-
lematic surfaces and are therefore good biocompatibility mod-
els. Early soft tissue integration with vascularization at the
tissue-implant interface, without liquid filled capsule forma-
tion is often desirable. If a bone is fixed subperiosteally and
the implant is not integrated fully, movement between the
implant and tissue interface may cause the formation of a fi-
brous capsule around areas of the implant which may become
liquid filled. Liquid filled soft tissue fibrous capsules are not
desirable, as they prevent tissue integrating with the implant
and encourage infection because they may reduce vascular-
ization at the biomaterial tissue interface causing the creation
of an immunoincompetent zone and an ideal place for patho-
gen proliferation. Consequently, immune cells are less able to
defend the body against any bacteria that have entered at the
biomaterial tissue interface. Movement of the implant also in-
fluences fibrous encapsulation and may hinder fast integra-
tion into the body and also attract more inflammatory cells to
the site.
Where gliding tissues are concerned, it is thought that a non-
adhering fibrous capsule on the soft tissue side of an IFF im-
plant may reduce the chance of gliding tissues —such as mus-
cles and tendons—adhering to the implant. One example that
requires neighboring tissues to freely glide over the implant is
within orbital fractures where connective tissues should glide
freely and not adhere to the implant surface, or problems with
eye movement can occur. In the case of overlying tendons in
distal radius fracture treatment, current literature describes
how titanium and its alloys tend to lead to more intratendon
inflammatory reactions when compared to steel, leading to
tendon-implant adhesion, tendon damage which prevents
normal tissue motion and may cause limited palmar flexion,
and even tendon rupture. The intrusion of a plate can produce
Ca
P
lionstaMetal/oxide ion diffusion
Biological ion incorporation
Protein absorption
Protein conformational changes
Fig 1 An implant surface is never static within the body and undergoes
continual changes over time, even without mechanical abrasion.
22 AODIALOGUE 1 | 07
friction for the gliding tissue and is liable to become a site for
tissue adhesion and inflammation. These osteosynthesis ap-
plications require the development of surfaces that prevent
soft tissue attachment and irritation, allow tissue gliding, but
maintain their biocompatible properties. It is highly unlikely
that a liquid filled void could occur within these situations,
due to the large movements of the gliding tissues. One way to
reduce the tissue adhesion would be to reduce surface micro-
roughness of the plate in contact with the tissue. Our work
strongly indicates that the surface topography of the titanium
(or even titanium alloy such as Ti15MO, used in hand sur-
gery), rather than the material itself is responsible for this
problem and polishing of the surfaces of plates in contact with
gliding tendons could prevent it. X-ray photoelectron spec-
troscopy results showed that the surface chemistry of anod-
ized polished metals (titanium and its alloys) did not differ
from the chemistry of the standard (as used in clinics) micro-
rough metals. Therefore, the polishing method tested should
be suitable for clinical use, where soft tissue adhesion is not
desired.
Bone With long term or permanent implants, such as spine
cages or chondylar plates in CMF, osseointegration is vital to
their success. Bony integration is increased on implant sur-
faces with higher amounts of microroughness and this is also
seen in the areas of prosthetics (hips and knees) and dentistry
(stents). The majority of research within these areas is into
increasing bony integration.
IFF devices are often removed to avoid: growth disturbances
in pediatrics; delayed infection; implant migration/breakage;
allergic reactions; soft tissue irritation; implant protrusion/in-
trusion (eg, into a joint); build up of fretting particles in unre-
lated organs (from loose multi component implants), as well
as being cosmetically disturbing (protrusion under skin). The
necessity of IFF implant removal is chiefly within the pediat-
ric population. Advocates of life long retention maintain that
difficulty in removing a device due to extraosseous formation
warrant their preservation to avoid complications such as in-
creased operative time, blood loss, and debris contamination.
Problems associated with excessive bony overgrowth account
for ~7% of all complications encountered. In temporary im-
plants such as plating, nailing with the use of screws or the
application of external fixators, minimal bone bonding to im-
plants is desirable for the least traumatic explantation. Strong
bony integration is a disadvantage when considering removal
and the surface microstructure is the major determinant of
this.
Our in vitro work with osteoblasts has shown that surface
polishing acts on a cellular level in that implant surface topog-
raphy influences both osteoblast proliferation and differentia-
tion. We have shown that surface polishing can significantly
reduce expression of osteocalcin, a principle factor involved in
bone mineralization, thus essentially inhibiting the cells abil-
ity to mineralize and form a mature matrix. Moreover, an in-
verse relationship has been observed between osteocalcin
gene expression and total DNA content, indicating a less dif-
ferentiated osteoblast phenotype to be present on polished
smooth samples. The polishing therefore reduces subsequent
mineralization which shows that there is more to surface pol-
ishing than simple macro changes for friction of surface
roughness on the bony integration.
Our recent in vivo work assessed the effect of surface topogra-
phy of TAN and titanium (cpTi) screws with different surface
topographies (polished and microrough) in a sheep cortical
(tibial) and cancellous (rib) bone model over three time peri-
ods of 6, 12, and 18 weeks. The effect of implant topography
on bone adherence was evaluated mechanically by measure-
ment of the peak torque removal force and histologically to
assess the amount of bone present at the surface of the im-
plant. The results demonstrated that polishing both cpTi and
TAN resulted in lower removal torque than standard micror-
ough screws when placed into cancellous bone. Polished cpTi
screws also had a lower removal torque when implanted in
the cortical bone. Polished TAN screws did not have a signifi-
cantly reduced removal torque when implanted in the tibia
but at 12 and 18 weeks, there was a trend for a reduction in
removal torque. Histologically, the polished screws consis-
Fig 2 Scanning electron microscope images of
S aureus bacteria adhered to a) standard micro-
rough TAN, The bacteria are scattered all over
the surface in small clumps of 6 bacteria, b)
electropolished TAN. Bacteria are found to clump
in large clumps, with no small clumps of 6 or less
seen.
23expert zone
tently demonstrated a lower percentage of bone contact than
the standard microrough implants. This study demonstrates
that polishing can reduce removal torque and the percentage
of bone contact in vivo and thereby improve the ease of re-
moval of TAN and cpTi screws placed into cortical and cancel-
lous bone. Where nonpermanent implants are concerned,
having some fibrous material present (as in the case of these
polished cpTi and TAN screws) may be advantageous—be-
cause it can prevent the screw from becoming completely
overgrown by bone, allowing for easier removal without com-
promising its stability within the bone (which is based upon
thread design more than surface structure).
Current in vivo work in our group looks at locked-screw and
plate combinations since many removal problems have been
noted with various designs of such systems. TAN is commonly
used for screws (and plates with LISS) with cpTi being used for
the LCP plate. We believe that excess bone bonding to these
implants is the major cause of the difficulty in removing the
screws from the plates. The purpose of the study is to assess
the effect of surface treatment of LCPs upon direct bone con-
tact after 6, 12, and 18 month implantation times in sheep
tibial cortical bone. We anticipate that the polished surfaces
will demonstrate decreased bone bonding and decreased ex-
traction forces. The results of this investigation could have sig-
nificant impact on the surface design of locking-head screws
and LCP plates to avoid the clinical problems during removal
of the implant. A second area we are working on is intramed-
ullary nailing. IM nails are composed of either stainless steel
or TAN. TAN is preferred due to its better biocompatibility and
mechanical properties. However excess bone bonding to the
TAN nails, resulting in difficulty in their removal has been
described. TAN has a microrough surface since the alloy is a
mix of soft α and harder ß phases which gives a micro spiked
morphology after surface processing. This surface integrates
extremely well with bone (as shown in our previous work
with cortical screws in vivo and discs in vitro). We know that
polishing TAN smoothes these micro spikes within the TAN
surface, which should reduce the amount of direct bone con-
tact for the nails as well as removal torques. The difficulty in
removing nails due to excess bone on-growth has not been
described for steel, which is clinically used with a smooth sur-
face. After a 12 month implantation period the nails will be
extracted by a pull-out test and some nails will remain in situ
for histomorphometric evaluation. We anticipate that the pol-
ished TAN nails will demonstrate decreased bone bonding
and extraction forces. This finding could be used to recom-
mend changes to current surface treatments of intramedul-
lary nails to reduce complications seen with nail removal, es-
pecially in rapidly growing bone in pediatrics.
Infection Surfaces of IFF implants are generally designed to
encourage soft and/or hard-tissue adherence, eventually lead-
ing to tissue integration. Unfortunately, this feature may also
encourage bacterial adhesion. Soft-tissue infections and os-
teomyelitis are serious complications associated with im-
plants, particularly with open fractures, external fixation de-
vices, and intramedullary nailing. Consequences of implant-
associated infections include prolonged hospitalization with
systemic antibiotic therapy, several revision procedures, pos-
sible amputation, and even death. Serious complications are a
great problem due to the emergence of antibiotic resistant bac-
teria such as methicillin-resistant Staphylococcus aureus
(MRSA). Hence modifying the actual metal implant surface to
inhibit or reduce initial bacterial adhesion may be an option.
Our recent work has looked at visualization and quantifica-
tion of Staphylococcus aureus, Staphylococcus epidermidis, Strepto-
coccus mutans, and Pseudomonas aeruginosa adhering to various
surfaces including standard microrough cpTi and TAN sur-
faces, electropolished cpTi and TAN surfaces, and standard
electropolished stainless steel. Significantly more live bacteria
were observed on standard microrough TAN surfaces than on
the other metal surfaces. There was no significant difference
in the amount of bacteria found on the other surfaces. Such
an observation suggests that the standard microrough TAN
surfaces encouraged S aureus adhesion, and could lead to
higher infection rates in vivo. Hence polishing TAN surfaces
could be advantageous in osteosynthesis areas in minimizing
bacterial adhesion and lowering the rate of infection. In the
case of infection prevention chemistry and alternative tech-
nology with active biological surface modifications for pre-
vention of bacterial adhesion and infection at the implant site
will have a stronger future than pure topographical modifica-
tion.
Fig 3 Modified universal humeral
nails used in our current study on
nail removal. Left, polished test TAN
nail with mirror like surface, middle,
standard microrough surface TAN
nail with matt surface, and right,
polished standard surface steel nail
with smooth surface.
24 AODIALOGUE 1 | 07
Geoff, whose degree was in cell and immunobiology, com-
pleted a masters in electron microscopy and received a PhD in
cell adhesion at The University of Wales, Aberystwyth. He has
authored over 50 peer reviewed papers and more than 200
abstracts, has 1 patent and 2 are pending. He has supervised 6
PhDs, 13 masters, 3 medical theses, and 2 diplomas with sev-
eral more ongoing. He is cofounder and Editor-in-Chief of the
first and only online open access biomaterials journal: “Euro-
pean Cells & Materials” (www.ecmjournal.org) which has
4,850 registered readers worldwide and is indexed by Medline
among others. Geoff is an honorary Senior Research Fellow at
the University of Glasgow, honorary lecturer at Aberystwyth
University and has a 3 year visiting Professorship at Tokyo
Medical and Dental University, Japan. He is President of the
Swiss Society for Biomaterials and has organised many con-
ferences and symposiums within this field.
We have developed topographies to answer clinical questions
without having to worry about shelf life and other concerns
with chemical/biological modifications. Topographical modi-
fications can be robust, cheap, and permanent, whether in
storage or in the body and (in the case of metals) can override
other cues of information to the cell such as chemistry. This
gives topographical surface modification a good solid platform
to start from. On top of this, topographical surface modifica-
tions, unlike chemical modifications, should not need extra
approval before clinical use. Polishing various implant sur-
faces has the potential to reduce the torque required for their
removal, reduce soft tissue problems, and in the case of TAN,
reduce bacterial attachment.
In situations with either hard or soft tissue interactions with
biocompatible bulk materials, the ‘implant biocompatibility’
is determined more by the design and surface characteristics.
Without surface modification an implant may be biocompati-
R Geoff Richards, Prof Dr SciProgram Leader Bio-performance of
Materials & Devices
AO Research Institute, Davos, Switzerland
Fig 4 4-hole LCPs used with locking screws in our current cpTi
(silver), standard microrough cpTi (gold), polished anodized
titanium (blue) and electropolished stainless steel control
(silver).
ble in one anatomical situation, yet not in another. Polishing
is not the answer to everything, though may have use in cer-
tain clinical applications as mentioned within this article.
There is no ‘one surface’ for all applications and surfaces on
one implant interacting with different tissues need to be con-
sidered as separate entities.
25expert zone cover theme polytrauma management
Platelet-rich plasma for bone healing—to use or not to use?
Sebastian Lippross, Mauro Alini
Introduction At the beginning of the 21st century, the clini-
cal application of platelet-rich plasma (PRP) was considered a
breakthrough in the stimulation and acceleration of bone and
soft tissue healing. Since then, its use has been predominantly
in maxillofacial surgery as an autologous additive to bone
grafts and soft tissue transplants, although other indications
such as chronic diabetic ulcers and some standard orthopedic
procedures have been suggested. This article will clarify the
rationale behind the clinical application of PRP by reviewing
the literature and outlining some of our own observations in
basic research.
Platelets and the growth factors they release are essential for
regulating the cellular events that follow tissue damage. They
adhere, aggregate, form a fibrin mesh, and subsequently re-
lease a large variety of growth factors and cytokines. At least
15 different factors are known to be contained within plate-
lets [1–3], including platelet derived growth factor (PDRF-bb,
-ab und -aa isoforms), transforming growth factor-beta (TGF-
beta, -beta1 and -beta2 isoforms), platelet factor 4 (PF4), in-
terleukin 1 (IL-1), platelet-derived angiogenesis factor (PDAF),
vascular endothelial growth factor (VEGF), epidermal growth
factor (EGF), llatelet-derived endothelial growth factor
(PDEGF), epithelial cell growth factor (ECGF), insulin-like
growth factor (IGF), osteocalcin (Oc), osteonectin (On), fi-
brinogen (Fg), vitronectin (Vn), fibronectin (Fn) und throm-
bospontin-1 (TSP-1). The impact on bone and tissue regenera-
tion of most of these factors has been recognized by many
authors [4–13]. As opposed to an artificial composition of re-
combinant proteins, PRP maintains the natural concentra-
tions within a cocktail of growth factors acting on multiple
pathways [14]. Furthermore, artificial recombinant growth
factors require further synthetic or animal proteins as carri-
ers. PRP in contrast serves as a natural carrier itself [15].
Thereby PRP can mimic the highly efficient in vivo situation
much more closely than a custom designed protein prepara-
tion.
As platelet concentrates can be prepared from whole blood
within a short time using relatively simple methods, they have
the potential to be an immunogenically inert additive to pro-
mote rapid healing and tissue regeneration. Preparation of
platelet concentrates usually requires a two step centrifuga-
tion procedure [16]. In the first step full blood is divided into
a platelet-containing and a cell-containing fraction [17]. Dur-
ing the second step, which is high speed centrifugation, plate-
lets can be sedimented and rediluted to the desired volume of
plasma (usually 1/10 of the initial blood volume) yielding
platelet concentrations of more than 1,000,000 platelets/μl
[15, 17]. To release the growth factors and cytokines, platelets
need to be activated. In vivo this happens through platelet
agonists like thrombin, collagen, ADP, serotonin, and throm-
boxane A2. For experimental purposes, bovine thrombin and
CaCl2 are the most commonly used agents. In our own studies
26 AODIALOGUE 1 | 07
we have demonstrated equal efficacy for freeze-thaw-activa-
tion of PRP [18]. In clinical practice PRP is used as a liquid,
made from 50–100ml of full blood that quickly forms a gel
when applied with thrombin. Several companies have devel-
oped kits and devices for automatic preparation during surgi-
cal procedures.
Although the general concept seems plausible, controversy re-
mains about whether PRP and other platelet preparations
meet the high expectations set by the clinical demands. For
the practitioner it appears very difficult to obtain information
on the actions and the possible risks of using platelet concen-
trates.
Clinical safety considerations Clearly an autologous prepa-
ration does not bear the risks of transmissible diseases nor of
immunogenic reactions. If commercially available devices are
used, FDA approval will usually ensure that the preparation
process is carried out in a sterile and pyrogen free manner. We
are not currently aware of any serious adverse effects that
have occurred when PRP was used for wound healing and
bone grafting. Still, a possible risk arises from bovine throm-
bin that is used to activate PRP. Coagulopathies due to anti-
body formation against thrombin, Factor V, and Factor XI
have been reported after cardiac surgery [19, 20].
Basic research—in vitro and in vivo effects of autologous platelet concentrates While there are numerous case stud-
ies and small clinical trials on the clinical applications, knowl-
edge about the underlying effects at the cellular level is limit-
ed. Nevertheless, PRP has been shown to stimulate cell
proliferation of osteoblasts and fibroblasts and to upregulate
osteocalcin in these cells [21, 22]. In a recent study by our
own group we demonstrated the differentiation of mesenchy-
mal stem cells (MSC) into bone forming cells in the presence
Application Type of study Study design Conclusion Reference
Treatment of intra-
bony defects
Comparative
controlled clini-
cal study
70 interproximal intrabony osseous
defects were treated with PRP and a
ceramic porous hydroxyapatite (HA)
scaffold or HA and saline
Treatment with PRP and HA led to
significantly more clinical im-
provement than HA and saline
[32]
Treatment of intra-
bony defects
Randomized
clinical trial
(split mouth,
double masked)
Bilateral periodontal intrabony de-
fects were matched in 13 individuals
and treated only with a bovine xeno-
graft or with PRP
PRP significantly increased the
clinical periodontal response of le-
sions treated with xenogenic bone
grafts
[33]
Treatment of
infrabony defects
Prospective case
series
Five similar bilateral paired infrabony
defects were treated with autologous
platelet concentrate (APC) or a biore-
sorbable barrier membrane (MEM)
Similar gain in clinical attachment
level and probing depths in APC
and MEM treated groups
[34]
Lumbar spine fusion Prospective re-
view compared
to historical
results
23 individuals underwent transforam-
inal lumbar interbody spinal fusion
(TLIF) with PRP compared to histori-
cal results
2-year minimum follow-up
showed faster healing in the PRP
group, but no significant differ-
ence in the pseudarthrosis rate
was observed
[35]
Total ankle replace-
ment
Comparative
Study
114 and 66 Agility total ankle replace-
ments were performed without and
with autologous concentrated growth
factors for distal syndesmosis fusion
Autologous concentrated growth
factors appeared to make a sig-
nificant positive difference in the
syndesmosis union rate in total
ankle replacements
[36]
Treatment of mandib-
ular continuity de-
fects in tumor cases
Prospective
study
44 individuals were treated with bone
graft and PRP and bone graft alone
Maturity index of bone grafts
with PRP was higher than in bone
grafts alone
[37]
Table 1 Application in bone healing
27expert zone cover theme polytrauma management
of PRP [18]. An increase in growth and differentiation of PRP-
treated periodontal ligament cells has been shown by two
groups [10, 23]. Further investigation revealed stimulation of
the mitogenic (ie, transforming) response to PRP in human
trabecular and rat bone marrow cells [24, 25]. Additionally,
we were able to demonstrate a strong effect on the expansion
of endothelial progenitor cells by platelet-released growth fac-
tors [26].
In vivo studies do not support the positive actions of PRP. In
fact, in one of the most recent investigations PRP decreased
the osteoinductivity of demineralized bone matrix in nude
mice [27]. Other researchers performed trials on various ani-
mals and reported no beneficial effect of using PRP for bone
healing [28] or suggest a low regenerative potential for its use
in combination with xenogenic bone grafts [29]. Some studies
also show effective augmentation of porous biomaterial in rats
[30] and sheep [31]. Careful analysis of these studies reveals
that none are scientifically comparable. Therefore, we cannot
draw an overall scientific conclusion of PRP actions in animal
models.
Clinical trials and case studies Case reports and small clin-
ical trials have been reported in craniomaxillofacial surgery
as in other specialties. Table 1 and table 2 display a selection of
such studies which overall support the beneficial effect of PRP
and other platelet concentrates. As previously mentioned, in
animal studies the two main factors making it almost impos-
sible to compare any two of the studies published are the lack
of a standardized PRP preparation protocol (Table 3) and the
lack of commonly accepted evaluation criteria.
Application Type of study Study design Conclusion Reference
Treatment of chronic
ellbow tendinosis
Cohort study Out of a cohort of 150 patients with
chronic elbow tendinosis, 15 were
given one injection of PRP, and 5
were given one injection of bupiva-
caine
Pain was reduced in patients
treated with PRP compared to the
control group in this pilot study
[38]
Treatment of diabetic
foot ulcers
Prospective
randomized
controlled trial
40 individuals were randomized into
a PRP- and saline-gel group and fol-
lowed up for 12 weeks
Significantly more ulcers healed in
the PRP group
[39]
Treatment of diabetic
foot ulcers
Meta-analysis More than 25,000 cases of diabetic
foot ulcers were treated with and
without platelets
Ulcers treated with platelet con-
centrate were significantly more
likely to heal
[40]
Table 2 Other applications
Device Preparation time Platelet yield (whole blood) as stated by manufacturer
Company
GPS
(gravitational platelet separation)
12 min Up to 8 Cell Factor Technologies
PCCS (platelet concentrate collec-
tion system)
20 min Up to 7 Implant Innovations
Symphony II 15 min Up to 6 DePuy
SmartPReP 15 min Up to 9 Harvest Technologies Corp
Magellan 15 min Up to 10 Medtronic
Table 3 Commercially available preparation systems
28 AODIALOGUE 1 | 07
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19 Cmolik BL, Spero JA, Magovern GJ, et al (1993) Redo cardiac surgery: late bleeding complications from topical thrombin-induced factor V deficiency. J Thorac Cardiovasc Surg; 105:222–227.
Sebastian Lippross, MDBiomaterials and Tissue Engineering
Program
AO Research Institute, Davos
Mauro Alini, PhDHead of Biomaterials and Tissue
Engineering Program
AO Research Institute, Davos
Summary and conclusions PRP preparation provides a
fairly simple method to deliver a variety of natural growth
factors to the patient. High concentrations of proteins acting
in concert through different pathways can be achieved by
commercially available systems that can be used in the oper-
ating room. The risks of contamination and immunogenic
response are considerably low when using FDA approved sys-
tems. The remaining risk of coagulopathies could be mini-
mized by using alternative activation methods to standard
bovine thrombin. On the whole, the beneficial effects of PRP
in clinical application remain doubtful. No appropriate clini-
cal investigations that meet all modern quality criteria have
been conducted up to now.
Based on our own and other groups’ in vitro findings, one
could hypothesize that PRP can be supportive of the healing
processes if used in the right manner. The appropriate use of
PRP has yet to be determined by larger randomized controlled
trials. Additional basic investigations on the mechanisms of
action could elucidate under which conditions PRP can act as
a tissue healing additive.
29expert zone cover theme polytrauma management
35 Hee HT, Majd ME, Holt RT, et al (2003) Do autologous growth factors enhance transforaminal lumbar interbody fusion? Eur Spine J; 12:400–407.
36 Coetzee JC, Pomeroy GC, Watts JD, et al (2005) The use of autologous concentrated growth factors to promote syndesmosis fusion in the Agility total ankle replacement. A preliminary study. Foot Ankle Int; 26:840–846.
37 Marx RE, Carlson ER, Eichstaedt RM, et al (1998) Platelet-rich plasma: Growth factor enhancement for bone grafts. Oral Surg Oral Med Oral Pathol Oral Radiol Endod; 85:638–646.
38 Mishra A, Pavelko T (2006) Treatment of chronic elbow tendinosis with buffered platelet-rich plasma. Am J Sports Med; 34:1774–1778.
39 Driver VR, Hanft J, Fylling CP, et al (2006) Autologel Diabetic Foot Ulcer Study Group. A prospective, randomized, controlled trial of autologous platelet-rich plasma gel for the treatment of diabetic foot ulcers. Ostomy Wound Manage; 52:68–70, 72, 74.
40 Margolis DJ, Kantor J, Santanna J, et al (2001) Effectiveness of platelet releasate for the treatment of diabetic neuropathic foot ulcers. Diabetes Care; 24:483–488.
20 Spero JA (1993) Bovine thrombin-induced inhibitor of factor V and bleeding risk in postoperative neurosurgical patients. Report of three cases. J Neurosurg; 78:817–820.
21 Graziani F, Ivanovski S, Cei S, et al (2006) The in vitro effect of different PRP concentrations on osteoblasts and fibroblasts. Clin Oral Implants Res; 17:212–219.
22 Dolder JV, Mooren R, Vloon AP, et al (2006) Platelet-Rich Plasma: Quantification of Growth Factor Levels and the Effect on Growth and Differentiation of Rat Bone Marrow Cells. Tissue Eng.
23 Annunziata M, Oliva A, Buonaiuto C, et al (2005) In vitro cell-type specific biological response of human periodontally related cells to platelet-rich plasma. J Periodontal Res; 40:489–495.
24 Gruber R, Varga F, Fischer MB, et al (2002) Platelets stimulate proliferation of bone cells: involvement of platelet-derived growth factor, microparticles and membranes. Clin Oral Implants Res; 13:529–535.
25 Oprea WE, Karp JM, Hosseini MM, et al (2003) Effect of platelet releasate on bone cell migration and recruitment in vitro. J Craniofac Surg; 14:292–300.
26 Lippross S, Verrier S, Hoffmann A, et al (2007) Platelet released growth factors boost expansion of endothelial progenitor cells [abstract]. 53rd Annual Meeting of the Orthopaedic Research Society 2007; Poster No 481.
27 Ranly DM, Lohmann CH, Andreacchio D, et al (2007) Platelet-rich plasma inhibits demineralized bone matrix-induced bone formation in nude mice. J Bone Joint Surg Am; 89:139–147.
28 Pryor ME, Yang J, Polimeni G, et al (2005) Analysis of rat calvaria defects implanted with a platelet-rich plasma preparation: radiographic observations. J Periodontol; 76:1287–1292.
29 Sanchez AR, Sheridan PJ, Eckert SE, et al (2005) Regenerative potential of platelet-rich plasma added to xenogenic bone grafts in peri-implant defects: a histomorphometric analysis in dogs. J Periodontol; 76:1637–1644.
30 Rai B, Oest ME, Dupont KM, et al (2007) Combination of platelet-rich plasma with polycaprolactone-tricalcium phosphate scaffolds for segmental bone defect repair. J Biomed Mater Res A.
31 Lucarelli E, Fini M, Beccheroni A, et al (2005) Stromal stem cells and platelet-rich plasma improve bone allograft integration. Clin Orthop Relat Res; 62–68.
32 Okuda K, Tai H, Tanabe K, et al (2005) Platelet-rich plasma combined with a porous hydroxyapatite graft for the treatment of intrabony periodontal defects in humans: a comparative controlled clinical study. J Periodontol; 76:890–898.
33 Hanna R, Trejo PM, Weltman RL (2004) Treatment of intrabony defects with bovine-derived xenograft alone and in combination with platelet-rich plasma: a randomized clinical trial. J Periodontol; 75:1668–1677.
34 Papli R, Chen S (2007) Surgical treatment of infrabony defects with autologous platelet concentrate or bioabsorbable barrier membrane: a prospective case series. J Periodontol; 78:185–193.
30 AODIALOGUE 1 | 07
Biotechnology in musculoskeletal surgery: outlook and expectations
Biotechnology represents a complex and diverse technical field
involving the fusion of modern biological methods that inno-
vate new products, capabilities and enabling technologies to
improve the quality of human life. Much argument abounds in
the literature on a single definition: each precise meaning de-
pends on field of use and context. In present economic terms,
biotechnology equates to drug innovation where modern
pharmaceutical pipelines are stocked with drug candidates
produced from biotechnology methods. But those same tech-
nologies are driving many other biomedical opportunities,
some relevant to musculoskeletal repair. A previous AO Dia-
logue article [1] and recent AO series book chapter [2] intro-
duced some general features of biotechnology use in medicine.
Most biotechnology strategies applicable to medicine are fo-
cused on new drug products from biotechnologies (eg, thera-
peutic peptides, proteins, and transgenes), incorporation of
these bioactive agents into delivery systems (carriers, coatings,
matrices), products of biotechnology (recombinant fibrin
glues, collagens, viral vectors, bio-engineered polysaccha-
rides), use of altered living cells as producers of therapeutic
agents or functional tissue replacements either in vitro (biore-
actors) or in vivo (cell therapy, regenerative medicine). Fur-
ther, active cells, therapeutic bio-derived compounds and bio-
materials are combined implant biomaterials (tissue engineered
constructs as cartilage and bone substitutes), and hybrid cell/
protein and chemical reporting constructs are exploited as ad-
vanced imaging tools (molecular beacons, genetically altered
cell probes, targeted molecular imaging agents). As capabilities
and creativity are unbridled, medicinal possibilities and surgi-
cal applications for these materials will only expand [3]. Meth-
ods in tissue engineering use many forms of biotechnology—
combining growth factors or other cell signaling molecules,
biomaterials scaffolds to provide form and support, seeded vi-
able cell populations to enable tissue regeneration, and appro-
priate bioreactors that promote recapitulation of viable tissue
form and function for novel implantable constructs. The ap-
proach is rapidly merging with regenerative medicine, often
used synonymously to signify the unified goal and strategy for
reproducing lost tissue or physiological functions with thera-
peutic and clinical potential. Bone and cartilage are primary
foci for biotechnology research, attempting to improve func-
tional tissue healing and neogenesis with varying degrees of
clinical success and failure.
From an academic perspective, biotechnology represents a
“blue sky” field: rapid advances have been made since the 1985
Nobel Prize was awarded for the polymerase chain reaction
and “recombinant” became routinely used in the Wall Street
Journal. The 21st century has been coined the “Century for
Biology” reflecting expectations of what diverse biotechnolo-
gy contributions might promise for therapeutic breakthroughs.
Nonetheless, the gap between preclinical research and clini-
cal applications is substantial. Many current biotechnology
studies provide ambivalent or starkly contrasting musculosk-
eletal outcomes. The lack of mechanistic details in many
‘cocktail’ approaches to treating difficult trauma situations
with mixtures of cells, genes, proteins, and biomaterials re-
flects the quite typical development of a complex field seeking
David W Grainger
31expert zone cover theme polytrauma management
simple solutions without many driving hypotheses. A con-
founding, dizzying array of biotech opportunities exist for
new approaches to trauma treatments, but many without sub-
stantial scientific validation to date. However, research prog-
ress must move from the current ‘black box’ and ‘blue sky’
endeavors to actually place significant tools in the hands of
clinicians. Table 1 highlights many possible areas where im-
pacting contributions are expected from preclinical to clinical
use. Several prospects and prognostications are reviewed
briefly below in some relevant areas.
1
Osteoporosis and fragility fractures. Anticipated biotechnology con-
tributions: advanced imaging, new interventional therapies, pro-
phylaxis.
Imaging New noninvasive imaging tools rely on new re-
agents with target-specific sensitivity and fidelity to provide
molecular and cellular level details. Molecular targeting and
imaging reagents are now combined with new optoelectronic
tools to improve lesion and tissue-specific contrast. Research
animals that express fluorescent proteins (GFP) in their cells
either constitutively, locally, or upon introduction of an exog-
enous cue are widely available. Hybrid molecular probes con-
taining both tissue specific agents and contrast agents that pro-
vide disease-specific activation via site-specific enzymatic
cleavage or targeting unfolding reactions have been developed.
Fiber-optic based tissue imaging is desirable using far red and
near-infrared (IR) light that travels through tissues most effi-
ciently and thus often used for whole animal imaging. How-
ever, IR-active tissue probes for such systems are rare. Now,
protease-activatable IR-active imaging probes can reveal in
vivo cathepsin B enzyme activity specific to tumor sites and
this strategy should be extended to musculoskeletal tissue en-
zymes as well. Harvested autologous bone marrow cells can
also be retrovirally transduced to constitutively express
flourescent/luminescent fusion proteins and reintroduced to
the rat. Over 4 weeks posttransplantation, the whole body dis-
tribution of transduced rat cells has been monitored using
Biotechnology target Expectations
Improved in vivo models for preclinical
evaluations
Genetically altered small and large experimental animal models that more accurately
reproduce aspects of human physiology, disease, and healing
New bioreactor-based ex vivo/in vitro living
tissue equivalents and tissue phantoms
Reduced cost, more accessible living and non-living biomimetic models for testing
therapeutic manipulations of tissue and avoid animal use
Advanced patient diagnostics and rapid
genetic analysis
Rapid, molecular level diagnosis and biomarker profiling of bone and connective tissue
disease states and risks, prediction of optimal drug therapies (pharmacogenomics)
and outcomes
Treatment of osteoporosis and fragility
fractures
Advanced molecular imaging tools, improved diagnostic and screening reagents and
methods, new interventional therapies from innovative biopharmaceutical drugs and
new devices, improved patient identification and prophylaxis
Improved cell and molecular biology
tools, methods and probes to advance
musculoskeletal research
Improved understanding of the biological basis of healing, identification of markers of
disease, genetically programmed cell types for therapies, exploitation of pluripotent
cells to program wound healing and bone neogenesis, cells as advanced imaging tools
Solutions to large bone defects, nonunions,
enhanced bone healing
Therapeutic gene and bioengineered growth factor delivery, tissue-engineered bone
regeneration, cell-based healing, reliable therapeutic vasculogenesis and new small-
molecule bone regenerative drugs
Mitigating infection Elucidation of pathogenesis mechanisms associated with implant-centered infection,
new anti-microbials addressing virulence and resistance mechanisms, new methods
to better deliver antimicrobials to implant sites, novel combination device and
biomaterials-based approaches to limit device and wound-site colonization
Reduce health care costs Depends upon regulatory and reimbursement strategies that provide economic
incentives, drive competition, and increase treatment options
Table 1 Anticipated biotechnology impacts on research, preclinical and clinical components of musculoskeletal repair.
32 AODIALOGUE 1 | 07
noninvasive bioluminescence imaging. Further novel molec-
ular and cellular homing agents, combinations with nano-
phased contrast agents (eg, particles) and associated instru-
ment innovation will continue to improve both resolution and
site-specificity in bone, cartilage, and connective tissue.
New drug targets Molecular and cellular studies reveal that
osteoblasts produce a protein signaling molecule—macro-
phage colony-stimulating factor—that induces macrophage
proliferation. A second osteoblast protein, RANKL, also binds
to a different macrophage receptor, inducing differentiation
into osteoclasts. A third osteoblast protein—osteoproteger-
in—blocks osteoclast formation by binding RANKL and
blocking its receptor interaction on macrophages. Parenteral
delivery of recombinant osteoprotegerin, a fragment of the
TNF receptor family protein (also called OCIF), to limit osteo-
clast formation, is a new therapeutic approach, reducing rates
of bone resorption by at least 60% in humans. Other molecu-
lar blockades against RANKL, such as recombinant antibod-
ies, are being developed with this capacity. Several other
known molecules in signaling pathways controlling bone for-
mation and resorption—including estrogen, parathyroid hor-
mone (PTH), and insulin-like growth factor-1 (IGF-1)—have
biotechnology development histories. Estrogen’s known nu-
clear transcriptional DNA regulation is also accompanied by
distinct osteoblast kinase-coupled receptor binding in bone
that prompts increased osteoprotegerin and reduced RANKL
production, suppressing osteoclast formation. Estrogen ex-
tends osteoblast survival while simultaneously inducing os-
teoclast death. Reduced estrogen levels accompanying meno-
pause decrease this inhibition of osteoclast formation and
resorptive activity, as well as bone building activity. PTH be-
haves in the opposite way by regulating RANKL and osteo-
protegerin to trigger osteoclast formation indirectly by bind-
ing to osteoblasts and prompting them to increase RANKL
and decrease osteoprotegerin production, respectively. De-
spite this resorptive action, the recombinant PTH fragment
(Forteo™, approved 2002, Eli Lilly) represents the first effica-
cious bone-building drug. Endogneous PTH at continuously
elevated levels over long periods promotes bone resorption;
periodic intermittent PTH injections build bone (known since
1928 from bone density studies in dogs but ignored for 50
years) by promoting osteoblast maturation and lengthening
osteoblast lifespan, enhancing numbers of bone-forming os-
teoblasts that function longer. In both men and postmeno-
pausal women, intermittently administered PTH increases
bone density (notably in spine), enhances bone structural in-
tegrity, and prevents fractures. Daily PTH injections increase
bone density 8–10% after one year, reducing fracture risk by
60%.
Wide differences in human serum IGF-1 levels, genetically
programmed but related in part to PTH levels, have important
implications for bone density and fracture incidence. IGF-I
normally circulates as a complex with the BP3 binding pro-
tein; appreciable free IGF-I is not normally found in blood and
is rapidly cleared from circulation. Administration of free
IGF-I at potentially therapeutic doses exerts acute insulin-like
side effects and lower doses exhibit limited, transient efficacy.
Somatokine™ (Insmed) is the biotechnology-derived recom-
binant equivalent of IGF-1 complexed with BP-3 in a single
molecule, studied for bone mass enhancement. Other, im-
proved biopharmaceuticals will likely result from biotechno-
logical discoveries regarding osteoporosis at the genetic, mo-
lecular and cellular levels, providing new therapeutic targets.
2
Bone defects, nonunions, enhanced bone healing. Anticipated bio-
technology contributions: gene-based and engineered growth factor
delivery, tissue engineered bone regeneration, cell-based healing,
therapeutic vasculogenesis, and bone regenerative therapies.
Biopharmaceutical therapies Similar to osteoporosis, new
biotechnologically derived drugs are sought to augment natu-
ral healing, accelerate bone formation and produce clinically
relevant amounts of new bone in areas of damaged or diseased
skeletal tissue. Many more protein-based drugs for bone neo-
genesis, primarily recombinant growth factors (eg, cytokines
and chemokines), have been reported than can be mentioned
here. Notably, the TGF-b superfamily of bone morphogenetic
proteins (BMPs) is the most studied and the most lucrative
clinical products to date. Recombinant human BMP-2
(rhBMP2, as InFuse™, Medtronics) enjoys a substantial in-
vestigative base and clinical use, mostly off-label. Many BMPs
have shown comprehensive bone inductive properties when
delivered locally either as the pure recombinant protein, or as
a transgene plasmid [4, 5]. Efficacy varies based on animal
model, patient age and health, wound site biology, and dosing.
Platelet derived growth factor (PDGF-BB) has produced prom-
ising results in several bone healing scenarios and appears
promising as another bone-targeted cytokine therapy. Two
primary limitations are evident in these cytokine delivery
strategies: (1) that a single growth factor is necessary but pos-
sibly not 100% sufficient to fully, reliably recapitulate rapid
bone regrowth, and (2) that direct delivery of the protein
agent to the wound site can often be dose and activity limit-
ing, with site-dependent efficacy. Multiple growth factor de-
livery is intuitive since this is precisely how cell-mediated
healing functions in vivo. However, multiple agent delivery to
bone sites lacks design parameters: sequential timing and dos-
ing of these endogenous agents in bone healing sites in vivo is
unknown and therefore rational duplication is impossible.
Nonetheless, several combination growth factor therapies
have been reported for bone formation [6, 7]. Delivery of the
33
therapeutic transgene for each cytokine (eg, BMP2, VEGF, or
PDGF) avoids limitations of direct protein drug delivery [8, 9].
However, control features on therapeutic gene expression (on/
off), duration, and dosing are currently problematic for reli-
able routine use. Delivery of multiple transgenes might better
duplicate endogenous BMP and cytokine synergies in vivo
[10]. Additionally, viral vectors, while extremely efficient for
transgene delivery to cells, are accompanied by serious risks of
immune reactions. Naked plasmids and nonviral gene deliv-
ery vectors are being studied as alternative gene delivery strat-
egies to bone, some with creative wound-healing responsive
designs [11], but are plagued generally by poor delivery effi-
ciencies in vivo and cell toxicity in some cases [12]. Future
biotechnology improvements are critical: new innovative
viral vector modifications to reduce local dose requirements
and host response, more effective nonviral vectors for local
gene delivery, and bioengineered cells (eg, ex vivo modified
stem cells) with introduced therapeutic cytokine genes tar-
geted to injury sites upon injection. New drug conjugates, re-
combinant protein signal molecules, and small molecule sur-
rogates with therapeutic mitogenic or morphogenic properties
in musculoskeletal repair are inevitable.
Cell-based approaches Many osteo-inductive biomaterials
have been described but their almost uniform disappointing
clinical performance to date is notable. Most notable recent
innovation in this area involves biomaterials scaffolds en-
hanced with biotechnology: tissue-engineered implantable
constructs capable of reproducing tissue form and function
using viable cells and potent drug combinations [13, 14]. To
improve in vivo performance, integrated understanding of in-
trinsic biological factors and kinetics governing bone and tis-
sue development in vivo, and their appropriate therapeutic
exploitation and functional control in situ are essential. Tis-
sue engineering methods are now inseparable from modern
pharmaceutics in using materials science, cellular and mo-
lecular biology to identify therapeutic targets, produce bioac-
tive substances and deliver them specifically to tissue sites to
promote specific biological responses. Most therapeutically
important neotissues will require production of transport-
competent organized vascular and neural networks for sur-
vival. Defect neovasculogenesis remains an unsolved prob-
lem: nothing regenerates without adequate perfusion. This is
limiting production of three-dimensional implants without
cell necrosis and viability issues. Numbers of requisite endo-
expert zone
34 AODIALOGUE 1 | 07
thelial progenitor cells vary enormously across species mak-
ing cross-comparisons difficult. The capability of angiopotent
cell types to adequately and rapidly restore perfusion to defect
sites to enable normal healing remains to be seen. Intraopera-
tive solutions to this problem are difficult. Biotechnological
enhancements of conventional scaffold approaches to bone
induction and regeneration require further work to distin-
guish themselves as reliable alternatives. It appears that sim-
ply mixing all biological components or primordial tissue into
a porous biomaterial and implanting it into a wound site is
insufficient in most cases to produce the desired clinical end-
point. That is, being present is not functionally equivalent to
timing and dosing of endogenous presentation.
Progenitor cell-based strategies represent an area of current
excitement and promise. Stem cell therapies are certainly po-
litically and scientifically dominant, but mesenchymal stem
cells in particular, with their capacity to differentiate to osteo-
blast, chondrocyte, fibroblast, and adipocyte cells, have at-
tracted substantial orthopedic and trauma attention [15, 16].
MSCs vary in their regenerative capacity, but have been used
successfully in human bone repair [17]. Identification of fac-
tors and pathways that promote reliable MSC osteogenic com-
mitment and allow use of MSCs with functional potential for
optimal bone repair remains a critical challenge. Age and
source-related regenerative variability are also important is-
sues. Bone-healing acceleration in response to osteogenic fac-
tors appears to result from increased recruitment in respon-
sive MSCs from the soft-tissue compartment around the bone
site, specifically sourced from muscle, fascia, vasculature, and
nerves (ie, cell recruitment and differentiation). Lastly, the
distinct roles of local biomechanical stimuli versus the intrin-
sic MSC mitogenic and morphogenic potential of the bone
healing site remain to be distinguished and exploited in mus-
culoskeletal healing scenarios. MSC coordination of vasculo-
genesis could be mechanically cued [18]. In these contexts,
further MSC genomic and proteomic analyses should help
identify molecules and mechanisms that promote reliable,
sustained osteogenic MSC mitogenic and morphogenic poten-
tial.
3
Infection. Anticipated biotechnology contributions: elucidation of
pathogenesis mechanisms associated with implant-centered infec-
tion, new antimicrobials, new methods to deliver antimicrobials to
implant sites, novel combination device and biomaterials-based ap-
proaches to limit device colonization.
Infection risk in an antibiotic-resistant era is a continuing
concern, and increasing implant incidence increases that risk
of infection [19, 20]. Modern pathology and infectious disease
research has been aided immensely by biotechnology meth-
ods. Model pathogen knock-outs, recombinant assay reagents,
and microbial genetic profiling provide enormous amounts of
new information about infection and disease, antibiotic resis-
tance mechanisms, and potential new antimicrobial targets.
This is now applied to device-centered infection problems and
elucidation of new antibiotics. Traditional synthesis of natural
antibiotics is often tedious, sometimes impossible or uneco-
nomical. Biotechnology methods permit fermentation of ge-
netically engineered microbial cultures to mass-produce com-
plex natural products and drug libraries beyond current reach
of organic chemists. Additionally, new antimicrobial bioma-
terials strategies to limit adherence and colonization, inacti-
vate pathogenic phenotypes (eg, by confounding microbial
quorum sensing), and locally deliver new antimicrobials more
effectively will emerge from biotechnology contributions to
this area. Infection prevention is much more effective than
post facto attempts to eliminate it, so that prophylaxis is more
attractive in new antiinfectives.
Other considerations for biotechnology Two further issues
cloud the horizon for clinical adoption of biotechnology: in-
surance reimbursement and regulatory strategies. Regardless
of research promise or clinical efficacy, these two hurdles rep-
resent rate-limiting steps to introducing experimental tech-
nology to the population at large. Reimbursement policies de-
termine to a large extent whether any medical innovation is
readily adopted by clinicians, and, importantly, whether bio-
technology firms (and their stockholders) can risk investment
into product development and innovation [21]. Regulatory
policies differ widely in biotechnology across countries and
continents [22]. Transparent, uniform processes are currently
lacking. The United States in particular faces a landmark deci-
sion in 2007 about regulating so-called bio-generics—phar-
maceuticals of biotechnology origin coming off patent. This
policy will dictate to a large extent financial requirements for
bringing new biotechnology products through the approval
path to market, and how future products will be developed
and innovated with this model, and in what specific clinical
areas [23]. Cell therapy products in particular remain an out-
standing example of research intrigue and promise, and regu-
latory doubt: such therapies might not offer product designs
for wide clinical adoption that can pass through regulatory
requirements with sufficient market economics to provide in-
centive for their development [24, 25].
Acknowledgements: The author thanks the many colleagues
who have imparted valuable perspectives, wisdom, and in-
sight. The field is far too big to go at it alone.
35expert zone cover theme polytrauma management
David W Grainger, PhDMember, AO AcC, BAB
Inaugural George S & Dolores Doré Eccles Presidential Endowed Chair of
Pharmaceutics and Pharmaceutical Chemistry, and Professor of Bioengineering
Departments of Pharmaceutics and Pharmaceutical Chemistry, and Bioengineering
University of Utah, Salt Lake City, USA
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36 AODIALOGUE 1 | 07
Pelvic and acetabular fracturesPast, present, and future
Introduction This article is a written summary of the Marvin
Tile 2006 Lecture given by Martin Bircher. The Marvin Tile
Lecture is given at the University of Toronto Pelvic and Ace-
tabular Fracture course to recognize Marvin Tile for his out-
standing contributions to orthopedic surgical teaching and in
particular his commitments to pelvic and acetabular fracture
treatment. In 1987, Mr Bircher was a Marvin Tile fellow when
his passion for trauma management and treatment of pelvic
and acetabular injuries was ignited. Mr Bircher returned to
London, England, where he put his passion into action, be-
coming one of the most respected pelvic and acetabular frac-
ture surgeons in the United Kingdom. This paper entitled
“Pelvic and acetabular fractures—past, present, and future”,
provides us with an overview of where we have come from so
as to aid in planning for the future.
The past In ancient China and Egypt there is abundant evi-
dence for the treatment of orthopedic injuries including frac-
tures of the pelvis. Mummified bodies have been found with
overlapping of the pubic symphysis [1]. These may have been
caused by some unpleasant injury, perhaps crushed by large
stones being used to construct pyramids. However it is more
likely that these deformities were caused by the process of
mummification and bandaging itself. Perhaps overzealous
pelvic sheeting!
In India, surgery was developing with instruments devised to
release ligaments, and traction apparatus to reduce disloca-
tions of the hip. In Ancient Greece there are descriptions of
wounds about the pelvis being caused by arrows, and pelvic
and acetabular fractures being caused by heavy stones.
Hippocrates actually classified hip dislocation [2]. He de-
scribed inward, outward, backward, and forward dislocations
of the head of the femur in relation to the pelvis. He devised
strategies for relocation, emphasizing the importance of a dif-
ferent technique for each different type of dislocation.
Around the time of the birth of Christ, anatomy became of
great interest. Accident surgery had also become very impor-
tant. Avicenna (980–1087 AD) produced many texts in Arabic
describing anatomical structures and he again emphasized
the underlying principles of fracture treatment outlined by
Hippocrates [3].
In 1066, William the Conqueror arrived in England and de-
feated King Harold at the Battle of Hastings. William was a
warrior who had no interest in medicine and spent his years
pacifying the unruly British. It is widely reported that Wil-
liam the Conqueror died of a ruptured testicle but I believe he
actually died of the complications of a pelvic injury. Although
a ruptured testicle would be acutely painful, it will not in it-
self lead to death. I believe the sequence of events were as fol-
lows: William’s wife became increasingly irritated by his en-
larging frame. In 1087, she sent him to Rouen to go on a diet.
On the way he was involved in a skirmish (he could not really
resist a fight). In those days saddles had a very high pommel
and as his horse stumbled he was thrown against the pommel
Martin Bircher
37expert zone cover theme polytrauma management
and sustained a symphyseal separation. I often see these in
modern day horse riders, particularly in North America where
saddles are of a slightly different design than in Europe. This
would account for his external injuries which I think were
misinterpreted as a testicular rupture. I believe he sustained a
symphyseal separation and injury to the genito-urinary tract,
probably a urethral rupture. There would have been second-
ary contamination leading to septicemia and death.
During the Dark Ages, Europe saw very few ad-
vances in the specialty of orthopedics and in par-
ticular pelvic surgery. The modern specialty was
really born with the publication of Malgaigne’s
books on fractures and subluxations in 1847 [4].
At the same time in the United Kingdom, Sir
Astley Cooper (1768–1841) described various
pelvic fractures, making the distinction between
marginal stable fractures and unstable pelvic
ring injuries. At this stage it should be empha-
sized that all these observations were made on
clinical grounds with no x-rays. For an acute di-
agnosis to be made there had to be obvious visi-
ble or palpable displacement of bones. This is
why in Malgaigne’s books and atlas he only de-
scribes significantly displaced fractures and dis-
locations of the pelvis. There is some confusion
with modern day surgeons about what precisely
a Malgaigne fracture is. I believe if one studies
his books closely, he is describing what is now known as bilat-
eral sacral fracture or “jumper’s fracture”. These are the H-
shaped double vertical shear fractures that people sustain
when they fall or jump from a great height. There are usually
saggital transforaminal fractures of the sacrum accompanied
by transverse connections with translocation of the sacrum
and encroachment of the sacral canal. These injuries are usu-
ally complicated by neurological damage. Malgaigne describes
these fractures associated with people jumping from build-
ings that were on fire. He also describes novel techniques for
reduction of the fractures with the introduction of large
wooden rods into the rectum. The wooden rod would reduce
the translated sacral fractures into a better position. However,
the technique was usually complicated by gross abdominal
distension and he therefore went on to devise silver cylinders
with cannulas to allow the escape of air. He records one pa-
tient being able to walk home after such treatment after twelve
days despite “a little infection”! The modern specialty of ace-
tabular surgery was yet to be born.
With the introduction of x-rays, the subspecialty advanced
rapidly and different types of pelvic and acetabular fracture
were identified. Albin Lambotte (1866–1955) produced stun-
ning descriptions of techniques for fixing sacral fractures and
described the use of sacral bars [5]. He was truly the master of
all surgeries and significantly advanced the surgery of fracture
management. In the UK in 1948, Sir Frank Holdsworth (1904–
1969) produced his paper on dislocations and fracture disloca-
tions of the pelvis [6]. He was a student at Cambridge and St
George’s Hospital, Hyde Park. He undertook a number of ju-
nior positions at St George’s before becoming the first orthope-
dic specialist in Sheffield in 1937. His paper studied 50 patients
and made key observations—including the dangers of death by
bleeding and the complication of genitor-urinary injury. He
concluded that sacral iliac dislocation was an evil injury with
most patients suffering chronic permanent agonizing pain
whereas patients with ilio-sacral fracture dislocations (cres-
cent fractures) had a better overall outcome.
In the 1950s and 1960s, other than pelvic slings, the only sur-
gical treatment recommended for unstable pelvic injuries were
forms of external fixation. These became the gold standard
treatment of such injuries. George Pennal (1913–1976) work-
ing in the University of Toronto Anatomy Department, began
to identify subsets of pelvic fractures including lateral com-
pression injuries, vertical shear forces, and open book type
fractures. The study of the biomechanics led him to produce a
classification which was later further modified by Tile.
Meanwhile in Paris in the late 1950s and 1960s, Robert Judet
began attempting to treat displaced acetabular fractures sur-
gically. He felt that the outcomes with displaced acetabular
fractures following conservative treatment were unaccept-
able. He identified certain subsets of acetabular fractures that
did not do well with conservative treatment. These included
fractures that involved the tectum or roof and those fractures
where the hip was unstable. He described ten classic fracture
patterns (five basic and five complex). Judet also developed
38 AODIALOGUE 1 | 07
many surgical approaches, particularly the ilio-inguinal ap-
proach, for treatment of anterior acetabular injuries. His work
was continued by his student Emile Letournel who diligently
collected data, listed complications, and educated a large
group of surgeons including Claude Martinbeau, Joel Matta,
Geoffrey Mast, Keith Mayo, and Eric Johnson. Other sur-
geons visited Paris regularly, including David Helfet and Roy
Moed. Meanwhile in Toronto, Marvin Tile continuing Pen-
nal’s work, published the classification of pelvic fractures in
the Journal of Bone & Joint Surgery (1986), and brought the
specialty together with his comprehensive book entitled
“Fractures of the Pelvis and Acetabulum”. There have now
been three editions of Tile’s book (1984, 1995, and 2003).
With Tile’s teaching and the Sunnybrook fellowships, the
practice of pelvic and acetabular surgery has been advanced
and spread across the world. I was fortunate enough to be one
of his fellows in 1987. His books complement the equally bril-
liant text on fractures of the acetabulum produced by Emile
Letournel.
The present Presently in the developed world, a full time job
as a trauma surgeon is not considered compatible with a good
lifestyle. The hours can be inconvenient and other subspecial-
ties within orthopedics pay much more handsomely. For pel-
vic and acetabular fracture surgery to provide the greatest
benefit to the injured patient in all countries, certain issues
need to be urgently addressed. By providing a good pelvic
fracture service the trauma system as a whole will benefit.
Trauma hospitals are struggling financially and this is at least
partly due to the unsophisticated coded systems that are used
to define activity and thus funding. For example, there are
over 17 different ICD10 codes for pelvic fractures and over 40
codes relevant to the pelvis in the OPCS system. Better coding
systems need to be developed in order to allow prompt pay-
ment for the treatment of trauma patients.
However, some units, particularly within the USA, are avoid-
ing treating uninsured trauma patients as they drain resourc-
es. This is known in the United States as ‘dumping’. These is-
sues are not only causing clinical problems but also have a
major detrimental effect on training.
An example of these inefficiencies was highlighted in the
United Kingdom in 2002. After a frustrating year of delays in
the definitive treatment of pelvic and acetabular patients I
went public with an audit that demonstrated that, within my
locality, it was 12 days between injury and a definitive surgery
for a pelvic and acetabular fracture. This audit led to a number
of meetings with healthcare providers resulting in the intro-
duction of a special tariff for definitive pelvic and acetabular
fracture reconstruction. It was felt that if there was a better
financing capability, the delay would be reduced. This in some
ways helped the situation as trauma units started receiving
more money for the treatment of pelvic fractures. However
other injuries eg, open fractures, are still poorly resourced
and the trauma units are still struggling. Unfortunately a sub-
sequent audit in my unit between June 2004 and June 2005
showed that the mean delay between injury and definitive
surgery still remains 12.6 days. The steady increase in local
trauma that remains underfunded has absorbed the extra re-
source earmarked for pelvic fractures. Other meetings are
going on in order to try and further rectify this problem. These
problems I believe are mirrored across Europe and North
America.
What are the solutions? We must make trauma care attrac-
tive as a career to recruit young doctors, make sure they are
paid appropriately, and that they have good working condi-
tions. We need to apply political pressure and lobby our po-
litical masters.
39expert zone cover theme polytrauma management
There is some good news, certainly within the UK. We have
over a dozen specialist pelvic units with fellowship trained
surgeons. The new tariff will help to fund these units. Regular
courses are run across the world and we recently completed
another successful course in September 2006. The bad news is
that these unacceptable delays remain and the pelvic story is
somewhat deflected away from the fact that trauma systems
are failing across the world. We are also being flooded with an
increasing number of osteoporotic traumas associated with
our ageing population.
We need to collect data. With this in mind, the European Pel-
vic Association of Surgeons (EPAS) has been formed. This will
give us teeth. We also need to evolve better coding systems
and continue educating ourselves, the public, and the politi-
cians.
The future The immediate future of pelvic and acetabular
surgery, in my opinion, should mainly focus on organization-
al changes. Systems need to be defined. Education needs to
continue. Trauma, and particularly pelvic and acetabular sur-
gery, needs to be brought to the forefront and inadequacies of
our systems need to be highlighted to the politicians and the
public. We should continue developing fine instruments and
strive to develop new techniques to make the surgery of pelvic
and acetabular fractures safer. With this in mind, computers
will come to the forefront. Image guided surgery combined
with sophisticated preoperative imaging will allow more fo-
cused treatment and less extensive incisions which are associ-
ated with a high complication rate. These advances, however,
will not be possible if cases are delayed and callus forms
around fracture surfaces. Indirect reductions are impossible
under these circumstances. It would be an advantage to have
new gadgets eg, talking drills that tell you the length of the
screw, self-tapping biodegradable implants, precontoured
plates, fracture glue, and some form of bone restorer.
We need to link up with our hip revision surgical colleagues
to deal with this influx of osteoporotic acetabular trauma. In
the acute phase, reconstruction is sometimes impossible or
fruitless. It is now recognized that techniques, other than re-
construction, are available and are indicated when fractures
are very comminuted or bone quality is poor. Within our unit
at St George’s, there is close liaison between the fracture group
and the hip reconstruction revision group.
In the more distant future, robotic surgery may become a pos-
sibility. On the biological front, there is encouraging work on
cartilage replacement and nerve regeneration. We are still
confronted on a regular basis with young patients with large
areas of primary articular cartilage damage occurring at the
time of an acetabular injury. Primary articular cartilage loss is
irreversible and until we have a system of replacing it, we will
not achieve good long term outcomes following a reconstruc-
tion of such injuries. One of the more devastating complica-
tions following a pelvic fracture is lumbo-sacral nerve injury.
Young men are rendered impotent and women suffer neuro-
logical pelvic floor symptoms. In the future we may be able to
replace areas of injured nerve thus reversing neurological
damage, impotence, and pelvic floor weakness.
In the more distant future spare part surgery may become an
option. New acetabular sockets may be available and perhaps
whole sacral units with nerves attached may be pulled “off the
shelf”.
If one looks at a UK £2 coin you will see written around the
edge the saying “standing on the shoulders of giants”. Our un-
derstanding and advancement of pelvic and acetabular sur-
gery relies on the work of our forefathers. I am privileged to
have stood on the shoulders of Marvin Tile and will always be
grateful for the teaching and advice he has given me.
Bibliography
1 Wenz W, et al (1975) Blick in die Vergangenheit. “Ägyptische Mumie im Röntgenlicht”. Adiologe; 125: 45–49.
2 Lithington ET (1828) Hippocrates. London. Loeb classic library Vol III.3 Varusis Amidas (2001) History of Orthopaedics. Athens.4 Malgaigne JF (1847) Traite des fractures et des luxations,
2 volumes.5 Lambotte A (1913) Chirurgie Oreratoire du Fractures. Paris,
Masson et Cie.6 Holdsworth FW (1948) “Dislocations and Fracture Dislocations of
the Pelvis”. J Bone Joint Surg Br; 30:461.
Martin Bircher, MDUnited Kingdom
40 AODIALOGUE 1 | 07
AO DebateAcute on chronic, unstable slipped capital femoral epiphysis
Steven L Frick and Virginia Casey
Acute on chronic, unstable slipped capital femoral epiphysis is
a common condition that faces the orthopedic surgeon in the
emergency department or the clinic. For many years, either in
situ pinning or gentle closed reduction and in situ pinning has
been recommended. Recently, with a newer understanding of
the hip blood supply and the concept of femoral acetabular
impingement as a cause for osteoarthritis, interest in the pos-
sibility of open reduction and pinning was renewed. This de-
bate will explore the two options.
Case presentation A 12-year-old male was presented to the
emergency department by ambulance after tripping and fall-
ing in the playground at school. He was unable to get up and
could not bear weight on his left lower extremity. He reported
3 months of left knee pain and occasional limping prior to the
fall. He had an unstable slipped capital femoral epiphysis on
the left that was completely displaced (Fig 1a–b).
What is the best surgical treatment for this patient? Is it emer-
gent or urgent? What is his risk of osteonecrosis? What is the
role of intracapsular hematoma as a possible cause of osteone-
crosis?
Steven L FrickOpen reduction for acute on chronic slipped capital femo-ral epiphysis The recommended treatment for slipped capi-
tal femoral epiphysis (SCFE) has for years been pinning in
situ, regardless of the severity of the slip, as retrospective long
term follow-up studies reported higher complications and
poorer results with reduction or realignment procedures [1].
The case presented of an acute on chronic SCFE is better dis-
cussed in terms of physeal stability, as Loder has clearly de-
fined unstable SCFE (patient unable to bear weight) as the
major risk factor for osteonecrosis (ON) [2]. The classification
based on timing of symptoms previously used in the literature
is helpful in understanding the pathoanatomy of SCFE, which
differs from femoral neck fractures as the proximal femur re-
models in response to the slip. The callus that thus forms pos-
teromedially has important treatment implications.
Traditional teaching is that reduction of SCFE is dangerous
and may cause ON. The literature is unclear if this applies to
stable slips, unstable slips, or both. Standard treatment of un-
stable SCFE frequently describes unintentional reduction
during positioning prior to internal fixation in situ, and does
not recommend a formal reduction maneuver. Practitioners
are cautioned to avoid forceful manipulations and reductions
that may cause ON. An anatomical explanation for the in-
creased risk would be stretching the posteromedial retinacu-
lar vessels over the slip callus.
Major adverse sequelae of SCFE are ON, poor motion, and
early arthritis. Chondrolysis is less common in the era of can-
nulated screw fixation. Loder reported an ON rate of 50% in
unstable slips, and other reports cite a 10–50% risk. An arte-
riographic study of 5 unstable SCFE describes loss of the dom-
inant vessel supplying the epiphysis in 3 of the 5 when the
epiphysis is displaced, and in one case demonstrated restora-
tion of flow in this vessel after reduction. The study concluded
that in some unstable slips the vascular injury occurs at the
41expert zone cover theme polytrauma management
time of injury, and that reduction does not necessarily con-
tribute to the risk of ON [3]. Growing evidence shows that
residual anatomic abnormalities predispose patients to early
hip osteoarthritis (OA)—how much deformity is acceptable,
and how much remodeling potential a given individual has
are not yet clearly defined. For SCFE, long term studies (Wein-
stein) state that deformity can be tolerated well.
The idea that reduction of an unstable SCFE is dangerous is
not supported by more recent reports. Practically, some un-
stable slips cannot be pinned in situ as the neck is completely
displaced from the epiphysis. After 40 years of experience,
two centers reported only a 13% incidence of ON following
early manipulative reduction of acute SCFE, although not all
had open procedures or capsular decompression. Gordon et al
recommend early reduction of unstable slips with arthrotomy
(decompression) and cannulated screw fixation to lessen the
risk of ON. Open reduction of unstable SCFE has been advo-
cated [4, 5], with the advantage of decompressing any intra-
capsular hematoma, and allowing some direct assessment of
reduction. The disadvantage is that closed reductions and
open anterior approaches do not allow visualization and re-
moval of posteromedial callus. This leads to the recommenda-
tion to reduce unstable slips to their “stable” or “preacute”
position—ie, to the position that will not stretch the capsular
vessels over the callus. To decrease the risk of ON, the surgeon
accepts residual deformity that may predispose the patient to
poor motion and early OA.
Ganz et al [6] have increased our knowledge and understand-
ing of the blood supply to the femoral head, and also of the
effects of proximal femoral deformity on hip joint longevity
and function, with an emphasis on femoroacetabular im-
pingement (FAI) as a cause of early OA of the hip. The detailed
studies of proximal femoral arterial anatomy [7], develop-
ment of an anatomically based surgical approach and clinical
series of safe surgical dislocation of the hip [8] offer a new way
to address SCFE. The potential adverse effect of intracapsular
hematoma on femoral head blood flow has also been con-
firmed, showing that increased intracapsular pressure can de-
crease perfusion to the epiphyseal region and may contribute
to ON following femoral neck trauma (Ng and Cole).
Leunig et al reported utilization of the Ganz surgical disloca-
tion approach for SCFE in an article that primarily described
the intraarticular changes noted in SCFE patients intraopera-
tively consistent with FAI. No patient developed ON (3 had
acute on chronic SCFE), and the research from this group has
led others to begin using the surgical dislocation approach to
address SCFE pathology, including the unstable slip. If this
approach can result in a decreased incidence of ON following
unstable SCFE, it may become the standard treatment method
as it allows restoration of normal anatomy that should also
improve motion and lessen the risk of early OA. Surgical dis-
location of the hip allows circumferential visualization of the
femoral head and neck, with the piriformis and importantly
obturator externus tendons intact to protect the vascular sup-
ply. The exposure of the femoral neck must be done with care
and must not damage the vessels within the periosteum and
capsular layer posteromedially. This exposure affords visual-
ization of the remodeling and callus along the posteromedial
femoral neck, which can then be removed to allow complete
reduction of the slip deformity without stretching the vessels
over the callus and compromising perfusion. The position of
the head on the neck can also be directly visualized, lessening
dependence on radiographic assessments of head-neck align-
ment. It still remains to be seen whether or not this approach
can eliminate ON, or if the injury to the blood supply can
occur at the time of initial displacement and be unrecover-
able.
Recent literature supports reduction of unstable SCFE and
stable fixation with decompression of any intracapsular he-
matoma. The options for achieving this are closed reduction
and fixation followed by capsulotomy, open reduction via an
anterior approach, or surgical dislocation. Follow-up studies
(>2 years) are needed to document that surgical dislocation
can be done safely in patients with unstable SCFE.
Virginia CaseyClosed reduction and in situ pinning Slipped capital femo-
ral epiphysis (SCFE) is a common disorder that affects 0.2 to
10 adolescents per 100,000. It is characterized by displace-
Fig 1a–b Unstable slipped capital femoral
epiphysis.
b
c
b c
42 AODIALOGUE 1 | 07
a
ment of the femoral head on the metaphysis causing pain and
deformity. SCFE can be classified based on duration of the
symptoms (more traditional classification) or on physeal sta-
bility as described by Loder. Classification of symptoms based
on chronicity includes acute, chronic, and acute on chronic
categories. Older literature utilized this classification for data
collection. More recent literature characterizes slips accord-
ing to physeal stability, which has been found to be the major
determinant for the risk of developing osseous necrosis.
Treatment of chronic stable SCFE is not controversial. These
patients have no risk of osseous necrosis and do well with in
situ pinning [2, 9, 10]. However, significant controversy re-
mains for the optimal treatment of a child with an unstable
SCFE (patient unable to bear weight) be it acute or acute on
chronic in nature.
There are several factors to consider when treating unstable/
acute slipped capital femoral epiphysis. The most important is
the avoidance of osseous necrosis. SCFE with osseous necrosis
is more likely to have a poor functional outcome with the
need for subsequent surgery. Factors that may be associated
with the development of osseous necrosis include physeal sta-
bility, slip severity, age of the patient, timing of fixation, num-
ber of screws/pins for fixation, and reduction of the deformity.
Of these factors, the only predictor of osseous necrosis that is
consistent in the literature is physeal instability. The literature
cites a 10–50% osseous necrosis rate in unstable SCFE.
Few studies evaluate the treatment of SCFE. The papers that
do assess treatment are limited by small patient numbers, ret-
rospective designs, and significant treatment variability.
Treatments studied include: casting, in situ pinning, inciden-
tal reduction and pinning, formal closed reduction, pinning
with or without preoperative traction, and open reduction
with or without a number of different femoral osteotomies.
The most common treatments cited in a recent survey of the
POSNA membership revealed that 84% perform in situ pin-
ning after positioning or incidental reduction, 11.8% pin after
a formal reduction, and 3% perform an open reduction.
Reduction that is done with positioning and is “incidental” is
thought to reduce the acute component of an acute on chron-
ic slip. This allows for some deformity correction without
stretching the blood supply over the callous which forms on
the posterior-medial femoral neck in chronic SCFE. Peterson
demonstrated no increase in incidence of osseous necrosis
with closed reduction of acute SCFE. However, Tokmakova
found an increased risk of osseous necrosis even with a partial
reduction when compared to pinning in situ.
O’Brien and Jones have shown that even in patients with
moderate to severe SCFE there is extensive remodeling of the
deformity [11]. In these patients there was resorption of the
anterolateral femoral neck allowing near normal hip range of
motion with the exception of a loss of 5–20° of internal rota-
tion in some patients. Those patients with incomplete remod-
eling are candidates for a femoral osteotomy.
The long term literature on SCFE is favorable for the hips with
mild to moderate deformity and no osseous necrosis [1]. The
hips with severe deformity have increasing hip pain with
time. Those hips with osseous necrosis tend to do poorly. Thus
treatment is aimed at decreasing rates of osseous necrosis
while minimizing deformity. The literature does not support
an obvious best treatment option for unstable SCFE. Open
treatment using the Ganz surgical dislocation approach may
prove to decrease the rates of osseous necrosis and restore nor-
mal anatomy, though this is not yet supported in the litera-
ture.
In situ pinning and incidental reduction with pinning are
percutaneous techniques that are not technically difficult.
The known long term results of these treatments are as good if
not better than open reduction techniques that are techni-
cally more challenging and not as amenable to being per-
formed by general orthopedic surgeons. While time may prove
that new open reduction techniques are successful in the pre-
vention of osseous necrosis, current literature supports the
use of less invasive techniques and should be the mainstay of
treatment for unstable SCFEs.
b
c
Fig 2a–b X-rays after 4 weeks showing no change
in alignment of the hip.
43expert zone cover theme polytrauma management
Bibliography
1 Carney BT, Weinstein SL, Noble J (1991) Long-term follow-up of slipped capital femoral epiphysis. J Bone Joint Surgery Am; 73(5):667–674.
2 Loder RT, Richards BS, Shapiro PS, et al (1993) Acute slipped capital femoral epiphysis: the importance of physeal stability. J Bone Joint Surg Am; 75:1134–1140.
3 Maeda S, Kita A, Funayama K, et al (2001) Vascular supply to slipped capital femoral epiphysis. J Pediatr Orthop; 21(5):664–667.
4 Parsch K, Zehender H, Buhl T, et al (1999) Intertrochanteric corrective osteotomy for moderate and severe chronic slipped capital femoral epiphysis. J Pediatr Orthop B; 8(3):223–230.
5 Aronson J, Tursky EA (1996) The torsional basis for slipped capital femoral epiphysis. Clin Orthop Relat Res; (322):37–42.
6 Ganz R, Parvizi J, Beck M, et al (2003) Femoroacetabular impingement: a cause for osteoarthritis of the hip. Clin Orthop Relat Res; (417):112–120.
7 Gautier E, Ganz K, Krugel N, et al (2000) Anatomy of the medial femoral circumflex artery and its surgical implications. J Bone Joint Surg Br; 82(5):679–683.
8 Beck M, Kalhor M, Leunig M, et al (2005) Hip morphology influences the pattern of damage to the acetabular cartilage: femoroace-tabular impingement as a cause of early osteoarthritis of the hip. J Bone Joint Surg Br; 87(7):1012 –1018.
9 Kennedy JG, Hresko MT, Kasser JR, et al (2001) Osteonecrosis of the femoral head associated with slipped capital femoral epiphysis. J Pediatr Orthop; 21(2):189–193.
Fig 3a–b Osteonecrosis with collapse of the
femoral epiphysis.
b
c
Outcome The patient was taken urgently to the operating
room and underwent reduction to the “preacute” position by
placing him in traction on a fracture table, under fluoroscopic
guidance. The proximal femur was stabilized with a single 7.3
mm cannulated screw, and the hip was aspirated to decom-
press the intracapsular hematoma. The patient was kept on
crutches with limited weight-bearing for 4 weeks, and x-rays
then showed no change in alignment of the hip and good posi-
tion of the screw (Fig 2a–b).
The patient was then lost to follow-up. He returned at 11
months after his surgery complaining of left groin pain and a
limp, and x-rays at that time showed osteonecrosis with col-
lapse of the femoral epiphysis (Fig 3a–b).
10 Tokmakova KP, Stanton RP, Mason DE (2003) Factors influencing the development of osteonecrosis in patients treated for slipped capital femoral epiphysis. J Bone Joint Surg; 85-A(5):798–801.
11 O’Brien ET, Fahey JJ (1997) Remodeling of the femoral neck after in situ pinning for slipped capital femoral epiphysis. J Bone Joint Surgery Am; 59(1):62–68.
Suggestions for further reading
Aronsson DD, Loder RT (1996) Treatment of the unstable (acute) slipped capital femoral epiphysis. Clin Orthop Relat Res; (332):99–110.Gordon JE, Abrahams MS, Dobbs M, et al (2002) Early reduction, arthrotomy, and cannulated screw fixation in unstable slipped capital femoral epiphysis treatment. J Pediatr Orthop; 22(3):352–358.Mooney JF III, Sanders JO, Browne RH, et al (2005) Management of unstable/acute slipped capital femoral epiphysis: results of a survey of the POSNA membership. J Pediatr Orthop; 25(2):162–166.Notzli HP, Siebenrock KA, Hempfing A, et al (2002) Perfusion of the femoral head during surgical dislocation of the hip. Monitoring by laser Doppler flowmetry. J Bone Joint Surg Br; 84(2):300–304.Peterson MD, Weiner DS, Green NE, et al (1997) Acute slipped capital femoral epiphysis: the value and safety of urgent manipulative reduction. J Pediatr Orthop; 17(5):648–654.Rattey T, Piehl F, Wright JG (1996) Acute slipped capital femoral epiphpysis. Review of outcomes and rates of avascular necrosis. J Bone Joint Surgery Am; 78(3):398–402.
Steven L Frick, MDPediatric Orthopaedics
Residency Program Director
Department of Orthopaedic Surgery
Carolinas Medical Center
Charlotte, NC, USA
Virginia Casey, MDPediatric Orthopaedic Surgeon
OrthoCarolina
Charlotte, NC, USA
AODIALOGUE 1/07 Upcoming events
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