Upload
oliver-boggess
View
212
Download
0
Tags:
Embed Size (px)
Citation preview
HAD Unit III ReviewTom Eck [email protected]
Unit III Exam•A ton of material, but questions tend to be
a bit more targeted—be sure to use the TBL as a guide
•Lab: review the prosections, especially the pelvis ones
•Abdominal Wall•Perineum•Gastrointestinal Tract•Genitourinary•Lower Limb•Lymphatics•Embryology•Shelf
Abdominal Wall•Fascia Layers• Innervation – intercostals, iliohypogastric,
ilioinguinal•Musculature – rectus abd., obliques, quad.
lumborum •Vessels – inferior and superior epigastric•Hernias – inguinal, femoral, congenital•Abdominal folds
▫Median = urachus▫Medial = umbilical arteries (deoxygenated)▫Lateral = inferior epigastric vessels
1. When surgeons cut through the anterior abdominal wall below the arcuate line, which of the following do they NOT encounter?
Camper’s fa
scia
Scarp
a’s fasci
a
Anterio
r laye
r of r
ectus .
..
Posterio
r layer o
f rectu
s...
Transversa
lis fa
scia
13% 13%
20%
43%
10%
1. Camper’s fascia2. Scarpa’s fascia3. Anterior layer of
rectus sheath4. Posterior layer of
rectus sheath5. Transversalis
fascia
Layers of Anterior Abdominal Wall1. Skin2. Camper (fatty)3. Scarpa (fibrous)4. Muscles
-External Oblique -Internal Oblique -Transversus Abdominus
5. Transversalis Fascia (fibrous)6. Extraperitoneal Fat7. Parietal Peritoneum- Above the arcuate line, the aponeuroses of
the abdominal muscles ensheath the rectus abdominus
- Below the arcuate line, they pass in front of it
2. What would likely result from a vertical incision through the right semilunar line superior to the umbilicus?
Paralys
is of t
he right r
ec...
Isch
emia of t
he right r
ec...
Paralys
is of t
he right e
x...
Isch
emia of t
he right e
x...
23% 23%20%
34%1. Paralysis of the right
rectus abdominis2. Ischemia of the right
rectus abdominis3. Paralysis of the right
external oblique4. Ischemia of the right
external oblique
Innervation and Blood Supply to Rectus Abdominus
Semilunar Line
Innervation via Intercostals
Blood Supply via Superior Epigastric
Blood Supply via Inferior Epigastric
3. You palpate a mass lateral to the inferior epigastric artery and superior to the inguinal ligament. What is true of this hernia?
It alw
ays passe
s thro
ugh...
It is
encase
d in sp
ermatic..
.
It does n
ot pass
thro
ugh...
It passe
s medial to
femor..
66%
0%
22%13%
1. It always passes through the superficial inguinal ring
2. It is encased in spermatic fascia
3. It does not pass through the deep inguinal ring
4. It passes medial to femoral vein
Hernias of the Myopectineal Orifice•Superior to Inguinal Ligament = Inguinal
▫Direct: between medial and lateral umbilical folds (in Hesselbach’s Triangle) medial fold = obliterated umbilical artery lateral fold = inferior epigastric vessels
▫Indirect: lateral to lateral umbilical fold; may be congenital, due to failure of processus vaginalis to close
•Inferior to the Inguinal Ligament = Femoral▫Passes through the femoral canal medial to
the femoral veins
4. Which nerve supplies the efferent limb of the cremasteric reflex?
Iliohypoga
stric
nerve
anterio
r scro
tal nerv
e
Ilioingu
inal nerve
genita
l bra
nch of g
enit...
femora
l bra
nch of g
eni...
0% 0%
14%
70%
16%
1. Iliohypogastric nerve2. anterior scrotal nerve3. Ilioinguinal nerve4. genital branch of
genitofemoral nerve5. femoral branch of
genitofemoral nerve
Cremasteric Reflex
• Afferent Limb: femoral branch of genitofemoral nerve and ilioinguinal nerve
• Efferent Limb: genital branch of genitofemoral nerve
• Iliohypogastric Nerve (L1): skin above inguinal ligament
• Ilioinguinal Nerve (L1): skin of anterior scrotum and adjacent thigh
• Genitofemoral (L1, L2): skin below inguinal ligament, motor to cremaster
• Note: both the ilioinguinal nerve and the genital branch of the genitofemoral nerve pass through the inguinal canal
• Fascia Layers• Muscles – external urethral sphincter, external
anal sphincter, bulbospongiosus, ischiocavernosus• Innervation – Pudendal Nerve, primarily • Autonomics (i.e. point and shoot)
Perineum
5. When fluid deep to Scarpa’s fascia in the abdominal wall reaches the perineum, where does it accumulate?
just
under the sk
in
the su
perficia
l perin
eal...
the deep perin
eal pouch
the is
chioan
al fossa
6% 3%
46%46%1. just under the skin2. the superficial
perineal pouch3. the deep perineal
pouch4. the ischioanal fossa
Perineal Spaces (of Urogenital Triangle)
Levator Ani (Encased in Fascia)
Deep Perineal Compartment (External Sphincter, etc.)
Superficial Perineal Compartment (Ischiocavernosus, Bulbospongiosus, etc.) Perineal Membrane
Colles Fascia* Scarpa’s Fascia of Abdomen Dartos Fascia of Scrotum
Subcutaneous Fat Camper Fascia on Abdomen
Skin
Deep
Su
perfi
cial
*Note: also continuous with the fascia lata of the thigh, though fluid will not pass laterally
6. When anesthetic is injected near the ischial spine, which of the following areas retains sensation?
anal region
anterio
r labium m
ajora
posterio
r labium m
ajora
anterio
r labium m
inora
posterio
r labium m
inora
36%
24%
6%
15%18%
1. anal region2. anterior labium majora3. posterior labium majora4. anterior labium minora5. posterior labium minora
Pudendal Nerve• S2, S3, S4• the pudendal nerve supplies
ALL of the perineal muscles and ALL of the overlying skin…
• EXCEPT for the anterior scrotum/labium majora, which are supplied by the ilioinguinal nerve
• Path: exits greater sciatic foramen and wraps around the ischial spine to enter the lesser sciatic foramen, extending anteriorly to the perineum
Pudendal Nerve Block
• anesthetized it as it wraps around the ischial spine
• Pudendal Nerve Branches▫ Inferior Anal Nerves:
external anal sphincter, perianal skin
▫ Perineal Nerve: perineal muscles, perineal skin
▫ Dorsal Nerve of the Penis/Clitoris: external urethral sphincter
Block here
• Arterial Supply▫Foregut = Celiac Truck▫Midgut = Superior Mesenteric Artery▫Hindgut = Inferior Mesenteric Artery
• Portal Circulation• Biliary Flow• Innervation (Sympathetic and Parasympathetic)
• major relationships (i.e. superior mesenteric artery passes over the third part of the duodenum)
GI Tract
7. Which artery is in direct danger from an ulcer eroding the posterior wall of the stomach’s body?
common hepatic
left ga
stric
right g
astric
gastr
oduodenal
splenic
0%
11%
51%
30%
8%
1. common hepatic2. left gastric3. right gastric4. gastroduodenal5. splenic
The Celiac Trunk
• artery of the foregut• Three branches:
▫ Splenic ▫ Common hepatic▫ Left gastric
• Artery endangered by ulcer in posterior wall of first part of the duodenum?▫ Gastroduodenal
artery
Splenic Artery
Celiac Trunk
8. Which vessel(s) have reversed flow to permit a collateral circulation in this patient with chronic hepatitis?
periumbilic
al veins
left umbilic
al vein
gastr
ic veins
middle re
ctal v
eins
Infe
rior r
ectal v
eins
95%
3% 0%0%3%
1. periumbilical veins2. left umbilical vein3. gastric veins4. middle rectal veins5. Inferior rectal veins
Porto-Caval Anastamoses
1. Paraumbilical veins superficial veins of abdominal wall Caput medusae
2. Superior rectal veins Middle and Inferior Rectal Veins (Inferior Iliac Vein) Internal hemorrhoids
3. Gastric veins Veins of Lower Esophagus ( Azygous System) Esophageal varices
1,2,3
9. If the left renal vein becomes occluded near its termination, which of the following will result?
caput m
edusae
esophage
al varic
es
inte
rnal h
emorrhoids
left va
ricoce
le
right v
aricoce
le
0%
14%5%
73%
8%
1. caput medusae2. esophageal varices3. internal hemorrhoids4. left varicocele5. right varicocele
Memorize major branches/tributaries of the abdominal aorta and IVC as well as how they relate to each other. Be able to draw this out.
10. When the pain of acute appendicitis moves into the right lower quadrant from the periumbilical region, which nerves carry this sensation?
visce
ral a
fferents
from th
...
visce
ral a
fferents
from t..
visce
ral a
fferents
from t..
inte
rcosta
l nerves
5%
23%18%
55%1. visceral afferents from the
foregut2. visceral afferents from the
midgut3. visceral afferents from the
hindgut4. intercostal nerves
Referred Pain in Appendicitis•Initial pain = periumbilical; visceral
afferents from inflamed appendix refer to the T10 dermatome
•Later pain = LRQ; as the parietal peritoneum is irritated, somatic afferents from intercostal nerves (subcostal, iliohypogastric, etc.) transmit well-localized pain
•Arterial Supply•Follow the Urinary Tract•Female Reproductive Tract•Male Reproductive Tract
▫SEVEN UP (Seminiferous Tubules, Epididymus, Vas Deferens, Ejaculatory Duct, (Nothing), Urethra and Penis)
• Innervation (Sympathetic and Parasympathetic)
Genitourinary
11. If a surgeon were to accidentally lacerate one of the following, which would involve the least risk of hemorrhage?
susp
ensory
ligament
meso
variu
m
meso
salpinx
meso
metrium
round lig
ament
card
inal ligament
34%
9%
17%
26%
6%9%
1. suspensory ligament2. mesovarium3. mesosalpinx4. mesometrium5. round ligament6. cardinal ligament
Ligaments of the Female Reproductive Tract
• Broad ligament▫ Mesovarium▫ Mesosalpinx▫ Mesometrium
• Suspensory Ligament: carries ovarian neurovascular bundle
• Cardinal Ligament: carries the uterine artery, situated below the broad ligament
• Round Ligament (and Ovarian ligament): remnant of gubernaculum
12. What does this hysterosalpingogram demonstrate?
uterin
e fistula
endometriosu
s
fallo
pian tu
be obstructi
on
conge
nital o
varian agenesis
normal
anatomy
24%
12% 12%16%
36%1. uterine fistula2. endometriosus3. fallopian tube obstruction4. congenital ovarian
agenesis5. normal anatomy
• the female reproductive tract communicates with the peritoneal cavity via the fallopian tubes
• a major route for spread of infection
• basis for abdominal pregnancy
13. Which of the following is at greatest risk in a hysterectomy?
uterin
e artery
urete
r
urinary
bladder
ureth
ra
rectu
m
12%
79%
0%3%6%
1. uterine artery2. ureter3. urinary bladder4. urethra5. rectum
The Ureter
• Know the path of the ureter
• At risk for damage when the uterine artery is ligated
• Passes along the posterior abdominal cavity
• Crosses the external iliac artery lateral to the internal iliac artery below the pelvic brim
• “water under the bridge” - passes under the uterine artery, lateral to the lateral fornix of the vagina before entering the urinary bladder
14. Along which nerve(s) do fibers carrying pain from the prostate travel?
hypogastri
c nerve
sacra
l splan
chnic
nerves
pelvic sp
lanchnic
nerves
thora
coabdominal s
pla...
3% 3%
67%
28%
1. hypogastric nerve
2. sacral splanchnic nerves
3. pelvic splanchnic nerves
4. thoracoabdominal splanchnic nerves
Visceral Pain
• pain line = lower limit of peritoneum • above the pelvic pain line, visceral afferents
follow sympathetic fibers• below the pain line, visceral afferents follow
parasympathetic fibers• Pelvic splanchnic nerves carry
Parasympathetic fibers• Sacral splanchnic nerves carry Sympathetic
fibers (as do all other splanchnic nerves)• Don’t get hung up on pathways for autonomics
(i.e. greater splanchnic celiac ganglion, etc.; straight from Dr. Vasan); symptoms are more important
15. Which branch of the internal iliac artery supplies the superior portion of the bladder?
obtura
tor
umbilical
uterin
e
vaginal
superio
r vesic
le
6%
42% 42%
0%
9%
1. obturator2. umbilical3. uterine4. vaginal5. superior vesicle
The Internal Iliac Artery
•posterior division: superior gluteal, iliolumbar, lateral sacral
•anterior division: supplies the viscera of the pelvis from anterosuperior to posteroinferior
The Anterior Division
Obturator
Umbilical ( S. vesicle)
Vaginal
Middle Rectal
Internal Pudenda
l
Inferior
Gluteal
Uterine
Obturator Foramen
Greater Sciatic
Foramen Inferior Vesicle (in
males)
•Muscles, Actions, and Innervations•Same kinds of things as upper limb, except…
▫ligaments are stressed a bit more▫the foot matters <<< the hand▫In general, somewhat less detail required—
knowing muscle compartment often enough to define action and innervation
▫know all major nerve deficits, how to recognize them, and what structures are involved
Lower Limb
16. What action at the hip might be lost if the nerve that passes through the obturator foramen were damaged?
flexion
extensio
n
adduction
abduction
medial ro
tation
late
ral ro
tation
8%5% 5%
8%5%
68%1. flexion2. extension3. adduction4. abduction5. medial rotation6. lateral rotation
Medial Compartment of Thigh
• Innervation: obturator nerve• Receives blood supply, in part, from the
obturator artery• Muscles: adductors longus, brevis, and
magnus; gracilis, obturator externis*
• For most muscles, simply knowing the compartment will tell you its primary action
*The pectineus is the only muscle that contributes to adduction, but is not innervated by the obturator nerve.
17. If a tumor were to compress the structures that exit the greater sciatic foramen superior to the piriformis, which of the following might be lost?
thigh
extensio
n
hip abduction
foot e
version
posterio
r thigh se
nsation
urinary
continence
36%
28%
3%
25%
8%
1. thigh extension2. hip abduction3. foot eversion4. posterior thigh
sensation5. urinary continence
Greater Sciatic Foramen• formed from greater sciatic
notch, closed off inferiorly by the sacrospinous ligament and posteromedially by the sacrotuberous ligament
• the superior gluteal nerve innervates the gluteus medius, gluteus minimus, and tensor of the fascia lata all three provide hip abduction (and medial rotation); loss = “hip drop”
• thigh extension = tibial, inferior gluteal; • foot eversion = peroneal (superficial); • posterior thigh sensation = post. femoral cutaneous• urinary continence = pudendal (external urethral
sphincter)
18. What action at the hip would be most weakened by avulsion of the lesser trochanter of the femur?
extensio
n
flexion
abduction
adduction
elevation
5%
39%
5%
37%
13%
1. extension2. flexion3. abduction4. adduction5. elevation
Iliopsoas• The most powerful flexor of
the hip• Three muscles: psoas major,
psoas minor, iliacus• Psoas major and iliacus are
the only muscles that insert at the lesser trochanter
• Psoas major significant for signaling apendicitis, route for spread of infection to/from thigh
• Greater trochanter: most of the gluteal muscles; gluteus medius, minimus, gemelli, obturator internis, piriformis Lesser
Trochanter
Iliacus
Psoas Major
Greater Trochanter
Important Attachment Sites• Greater trochanter• Lesser trochanter• Tibial tuberosity = quadriceps femoris• Ischial tuberosity = hamstrings (except short head
of biceps femoris)• Base of 5th metatarsal = fibularis brevis• Base of 1st metatarsal = fibularis longus
• For most of the rest, simply knowing the bone (or general region) should suffice
19. Following injury, if you note ease in abducting the tibia, causing visual deformity (genu valgum), which ligament may have been damaged?
anterio
r cru
ciate
posterio
r cru
ciate
fibular colla
teral
tibial colla
teral
patella
r
16% 16%
6%
39%
23%
1. anterior cruciate2. posterior cruciate3. fibular collateral4. tibial collateral5. patellar
Ligaments of the Knee• The knee is the largest and least stable joint of the
body; know the deficits
• ACL = laxity in anterior displacement of tibia; connects lateral femoral condyle to anterior tibia
• PCL = laxity in posterior displacement of tibia; connects medial femoral condyle to posterior tibia
• FCL (lateral) = genu varum• TCL (medial) = genu valgum
• vaLgum = Lateral displacement of distal component• varum = medial displacement of distal component
• Coxa = hip; genu = knee; hallux = big toe
20. ID this ligament:
anterio
r cru
ciate
posterio
r cru
ciate
fibular colla
teral
tibial colla
teral
patella
r
50%
31%
19%
0%0%
1. anterior cruciate2. posterior cruciate3. fibular collateral4. tibial collateral5. patellar
The ACL and PCL
• The attachments of the ACL and PCL are important to know; they also explain why lateral rotation of the tibia—when the knee is bent—is greater than medial rotation
MEDIAL FEMORAL CONDYLE
LATERAL FEMORAL CONDYLE
ACL
PCL TIBIAL
PLATEAU
RIGHT KNEE JOINT FROM
ABOVE LATERAL ROTATION
The ligaments become lax upon lateral rotation and taut on medial rotation
The ACL and PCL
MEDIAL FEMORAL CONDYLE
LATERAL FEMORAL CONDYLE
ACL
PCL TIBIAL
PLATEAU
RIGHT KNEE JOINT FROM
ABOVEANTERIOR DISPLACEMENT
Only the ACL resists anterior displacement. Likewise, only the PCL resists posterior displacement.
21. In an individual complaining of “foot drop,” foot inversion is also weakened, but not abolished. Which muscle permits continued functionality?
flexor d
igito
rum lo
ngus
flexor h
allucis
longu
s
tibialis poste
rior
soleus
gastr
ocnemius
10%
27%
17%
7%
40%
1. flexor digitorum longus2. flexor hallucis longus3. tibialis posterior4. soleus5. gastrocnemius
Ankle Joint Movements
• “foot drop”: loss of deep fibular nerve, specifically, but most common injury occurs to the common fibular nerve as it winds around the neck of the fibula
• Inversion: tibialis anterior and posterior • Eversion: lateral compartment muscles• Plantar flexion: posterior compartment muscles• Dorsiflexion: anterior compartment muscles
22. Which nerve, when damaged, leads to anesthesia over the plantar surface of the foot?
tibial
deep fibular
superfi
cial fi
bular
femora
l
obtura
tor
50%
11%
0%
14%
25%
1. tibial2. deep fibular3. superficial fibular4. femoral5. obturator
Cutaneous Nerves of the Lower Limbs• Fairly important to know• Generally, knowing the
name of the cutaneous nerve is less important than knowing the major nerve it is derived from
• Tibial medial/lateral plantar
• Femoral saphenous• Know cutaneous
distribution of obturator, superficial peroneal, deep peroneal
•Memorize the lymph chart!!•Also study lower limb drainage•When in doubt—which there shouldn’t be
any—guess superficial inguinal!
Lymphatics
23. To which group of nodes does lymph from the 5th toe reach first?
popliteal
superfi
cial in
guinal
deep inguinal
extern
al iliac
inte
rnal il
iac
66%
26%
3%0%6%
1. popliteal2. superficial inguinal3. deep inguinal4. external iliac5. internal iliac
Lymphatics of the Lower Limbs
• Lymph following the drainage of the small saphenous vein popliteal ( deep inguinal)
• Lymph following the drainage of the great saphenous vein superficial inguinal
• Lymph following the deep veins of the legs deep inguinal
•Gastrointestinal – know foregut, midgut, hindgut derivatives; rotation
•Urinary – three stages of kidney development
•Reproductive – know the precursors to each adult structure; know the male/female homologs
•congenital abnormalities
Embryology
24. Which of the following is derived from the ventral mesentery of the stomach?
Gre
ater o
mentum
Lesse
r omentu
m
Splenore
nal liga
ment
Gastr
osplenic
ligament
Gastr
ocolic
ligament
50%
33%
6%11%
0%
1. Greater omentum2. Lesser omentum3. Splenorenal ligament4. Gastrosplenic ligament5. Gastrocolic ligament
Stomach Rotation
VEN
TRAL
DO
RSA
L
• The stomach rotates clockwise 90° during development
• Ventral mesentery lesser omentum
• Dorsal mesentery greater omentum
• The greater omentum can be divided into gastrocolic, gastrosplenic, gastrophrenic, and occasionally, splenorenal ligaments
25. Which of the following is derived from an embryo kidney structure?
uterin
e tube
prosta
tic utri
cle
susp
ensory
ligament
ductus d
eferens
round lig
ament
36%39%
0%
9%
15%
1. uterine tube2. prostatic utricle3. suspensory ligament4. ductus deferens5. round ligament
Urogenital Development
• The urinary tract and reproductive tract develop in close association with each other
• Much of the male reproductive tract is derived from the mesonephric duct of the second set of kidneys (mesonephros), including the ductus deferens
• Remember: Male = Mesonephric duct = Medulla-Derived Testis
• Female = Paramesonephric duct = Cortex-Derived Ovary
26. What restricts the normal ascent of a horseshoe kidney?
inferio
r mese
nteric
vein
inferio
r mese
nteric
artery
fuse
d bladder
shorte
ned ureters
6%
35%
15%
44%1. inferior mesenteric
vein2. inferior mesenteric
artery3. fused bladder4. shortened ureters
Horseshoe Kidney
• Because the IMA is the inferiormost vessel that branches off the aorta anteriorly, it will block the ascent of a horseshoe kidney
• This condition is asymptomatic
•The Bad News: cumulative final; limited study time
•The Good News: you’ve been preparing all along! The clinical approach the course directors employ is a good representation of what you’ll see. Also, questions tend to be less detail-oriented on the Shelf.
Shelf Exam
27. A 45-year-old woman has a uterine leiomyoma that is 5 cm in diameter and is pressing on the urinary bladder, causing urinary frequency. Which of the following is the most likely location of the leiomyoma?
cerv
ical c
anal
late
ral m
argin of u
terin
e...
subendro
metrially
in th
e...
subperit
oneally on th
e ...
subperit
oneally on th
e ...
3%6%
36%
42%
12%
1. cervical canal2. lateral margin of uterine cavity3. subendrometrially in the
uterine cavity4. subperitoneally on the anterior
surface of the uterine corpus5. subperitoneally on the posterior
surface of the uterine fundus
•First, don’t let the details of the clinical scenario intimidate you
•Who knows what a leiomyoma is?! Who cares!
•All we need to know is that its pushing on the bladder and causing increased urinary frequency
•You are well equipped to handle most questions; don’t assume anything is over your head
• The question is really just a convoluted way to test our understanding of how the uterus relates to the bladder
• Process of elimination • Cervical canal and
subendometrial are both inside the uterus
• Lateral margin – too far away
• Subperitoneally – good – on surface of uterus; anterior or posterior? anterior – uterus lies behind the bladder (this is what they were testing!)
What’s on the Test?
• Go to nbme.org and look for “Basic Science Subject Examinations” “Content Outline”
• You will find a breakdown of the topics and their representation; 20 sample questions – do them
• Last year’s exam• A ton of GI questions• Very little head and neck – if you dissect the content
outline, this is plausible• From asking around about previous years, I found
this to be a common observation
Study Suggestions
• My number one suggestion: make learning this unit your number one priority, since GI and pelvis tend to be strongly represented
• If you do that, you will leave yourself a day and a half to go over the first two units (especially unit I)
• Review Books: • BRS Gross Anatomy: detail can be a bit
overwhelming; focus on the pink boxes; comprehensive exam at end is fairly representative; chapter exams are somewhat detail-oriented (also try RoadMap, PreTest)
• High-Yield Embryology: embryo is 25 of 150 questions; high-yield has a reasonable level of detail, no questions
Study Suggestions
• Another good approach: review your TBL’s; the questions tend to cover the most clinically relevant material
• If you’re really ambitious, you might even consider reading through the Big Moore Blue Boxes (depending on how comfortable you are with the basic anatomy)
You’re almost there! Good luck!