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Operation, cast, or early controlled mobilizationTreatment for acute tears of the lateral ligaments of the ankle.

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www.jbjs.org20 Pickering Street, Needham, MA 02492-3157The Journal of Bone and Joint Surgery

Copyright 1991 by The Journal ofBone and Joint Surgery. Incorporated

VOL. 73-A, NO. 2, FEBRUARY 1991 305

Current Concepts Review

Treatment for Acute Tears

of the Lateral Ligaments of the Ankle

OPERATION, CAST, OR EARLY CONTROLLED MOBILIZATION

BY PEKKA KANNUS, M.D.*, AND PER RENSTROM, M.D.t, BURLINGTON, VERMONT

From the Department of Orthopaedics and Rehabilitation, University of Vermont, Burlington

It has been estimated that there is about one inversion

injury of the ankle per 10,000 people each day9’55’�, or

approximately 5,000 injuries in the United Kingdom and

23,000 injuries in the United States each day. Patients who

have a sprain of the ankle constitute 7 to 10 per cent of

those who are examined at the emergency departments of

the hospitals in Scandinavia77. Jackson et al.39 found this to

be the most common injury at the United States Military

Academy, West Point, with one-third ofthe cadets spraining

an ankle during their four years there.

A sprained ankle is the most common injury in

sports273050’55. In a prospective study in Gothenburg, Swe-

den, Axelsson et al.4 found that 18 per cent of the patients

who were treated at the emergency ward of a central hospital

for a sports-related injury had an acute sprain of the ankle.In similar studies in Finland69 and Norway57, acute sprains

of the ankle represented 21 and 16 per cent, respectively,

of all sports-related injuries.Sprains of the ankle occur in many sports. Garrick27

noted that injuries to the ankle accounted for 45 per cent of

injuries occurring during basketball and for 31 per cent of

those occurring during soccer. Sandelin69 observed that 29

per cent of all injuries of the lower extremities in soccer

were in the ankle, and that, of these, 75 per cent involved

the lateral ligamentous structures.

The lateral ligament complex of the ankle comprises

three major ligaments: the anterior talofibular, the calca-

neofibular, and the posterior talofibular. The anterior tab-

fibular ligament runs almost parallel to the axis of the foot

when the foot is in the neutral position, but when the foot

is in plantar flexion, this ligament assumes a course parallel

to the axis of the leg, thereby functioning as a collateral

ligament5’6. As most sprains occur with the foot in plantar

flexion, this ligament is the one that is injured most fre-

quently in inversion sprains.

According to studies by Brostr#{246}m’#{176}and Linstrand53,approximately two-thirds of sprains of the ankle are isolated

* Tampere Research Station of Sports Medicine, Kaupinpuistonkatu

1 , SF-33500 Tampere, Finland. Please address requests for reprints toDr. Kannus.

t Department of Orthopaedics and Rehabilitation, University of Ver-mont, Given Building, Burlington, Vermont 05405.

injuries to the anterior tabofibular ligament. If the inversion

trauma is more severe, the calcaneofibular ligament is also

involved. Brostr#{246}m observed that combined rupture of the

tabofibular and calcaneofibular ligaments occurred in 20 per

cent of his patients and that the cabcaneofibular ligament

was never ruptured alone.

Traditionally, in clinical practice, sprains of the ankle

have been classified as grade I (mild), II (moderate), or III(severe)5’6’4’20’50. A grade-I injury involves stretch of the

ligament without macroscopic tearing, little swelling or ten-

derness, slight or no functional boss, and no mechanicalinstability of the joint. A grade-Il injury is a partial mac-

roscopic tear of the ligament with moderate pain, swelling,

and tenderness over the involved structures. There is some

loss of motion and mild or moderate instability of the joint.In a grade-Ill injury, there is complete rupture of the big-

ament with severe swelling, hemorrhage, and tenderness.

There is loss of function and considerably abnormal motion

and instability of the joint.

Once the diagnosis has been made clinically and con-

firmed by stress radiographs or arthrography, or both, a

treatment regimen must be decided on. Almost all authors

have agreed that patients who have a grade-I or grade-Il

injury recover quickly with non-operative manage-

ment5’6’20’�#{176}and that the prognosis is, almost without ex-

ception, excellent or 5l920�39��556l .70, The treat-

ment program, usually cabled functional treatment, includes

three phases. Immediately after the injury, rest, ice (cold),

compression, and elevation (RICE) are used. Then a shortperiod of immobilization and protection with supportive

bandaging, taping, or bracing is utilized to control pain and

swelling. Finally, early active range-of-motion exercises are

started, followed by weight-bearing, proprioceptive training

with a tilt-board, and strengthening exercises for the per-

oneus muscle. Jackson et al.39 found that in cadets who

followed this type of regimen, the duration of disability was

eight days for a grade-I injury and fifteen days for a grade-

II injury.The treatment of grade-Il sprains of the lateral ligament

complex is more controversial. Many uncontrolled, non-

randomized studies have suggested that primary repair is

the method of choice, since most patients who had operative

306 PEKKA KANNUS AND PER RENSTROM

ThE JOURNAL OF BONE AND JOINT SURGERY

treatment seemed to have a mechanically stable ankle and

satisfactory subjective 34,47��6263�73 � However,

similar results have been reported after conservative treat-ment’ ‘ 15.2 I .35.3740.52.56

The cost of operative treatment is far more than that

of conservative treatment. For example, in 1980, the av-

erage cost of one acute sports-related injury in Finland was

$350 (United States dollars) if the patient was treated at the

casualty department but was thirteen times more ($4,500

[United States dollarsi) if a patient who had the same injury

was treated as an in-patient69.The importance of randomized clinical trials has been

emphasized in the recent orthopaedic literature28’5’ . In this

review, we examined twelve prospective randomized studies

of the treatment of acute grade-Ill ruptures of the lateral

ligaments of the ankle.

Prospective Randomized Studies

A review of the English-language literature revealedtwelve prospective randomized studies that had been carried

out for the purpose of identification of the proper treatment

of acute grade-Ill (complete) tears of the lateral ligaments

of the ankle’ � ,I7,24,25,33,46,48,58,59,61 .72.76

Age and Activity

The mean or median age of the patients was reported

in eight of the twelve studies, and it ranged from twenty-

three to thirty-two years. in the two earliest studies, from

19651725, the ages of the patients were not given, and in

two studies only the range of the patients’ ages (fifteen to

fifty years48 and twelve to fifty years59) was given. In tenstudies, high-performance athletes were included, and in

two48’72 studies, they were excluded.

Sex Distribution

in eleven studies, an average of 7 1 per cent of the

patients were men and 29 per cent were women. Korkala

et al.48 did not report the sex distribution.

Previous injuries

In six studies, patients who had had a previous sprain

of the ankle were excluded. In the studies by Brostr#{246}m�,

Prins6’ and Niedermann et al.59, 32, 26, and 21 per cent

of the patients had had one or more previous sprains of the

ankle. In the other three studies24’33’58, this information was

not given.

Diagnostic Methods

To be included in any of the studies, patients had tohave a typical history of injury and positive clinical findings

(talar tilt and an anterior drawer test indicative of a grade-

III sprain of the ankle). In addition, in every study at leastone radiographic method was used to confirm the clinical

diagnosis. In five studies’7’25’33�’48 stress radiography wasused, and in two studies�’59 arthrography was used for con-firmation. Both stress radiography and arthrography were

used in the other five studies24’58’6’72’76.

The arthrographic diagnostic criteria for an isolated tear

of the anterior tibiofibubar ligament and for rupture of both

the anterior tibiofibular and the calcaneofibubar ligament

were the same in all studies in which that method was used.

A detailed description of these criteria was given by

I and by Prins6’ . In the radiographic stress tests,the exact talar displacement (in millimeters) for a positive

anterior drawer test and the exact tabar tilt (in degrees) varied

among the studies, but in general they were consistent and

conformed to usual standards.

Ruptured Ligaments

The ratio of the number of patients who had an isolated

tear of the anterior tibiofibular ligament to the number who

had combined tears of the anterior tibiofibular and calca-

neofibubar ligaments varied, as a result of the slightly dif-

ferent diagnostic criteria that were used in each study. In

four studies’1�24�33�59 there were more isolated tears of the

anterior tibiofibular ligament than combination ruptures, and

in two studies58’76, the ratio was reversed. In two studies48’6’,all of the patients had rupture of both ligaments, and in the

other four’7’24’�’72 the ratio was not specified.

Treatment Protocols

All of these studies, except one72, compared at beast

primary repair of the ligaments and immobilization of the

distal part of the beg in a cast with only immobilization in

a cast. Sommer and Arza72 used elastic strapping and ban-

daging instead of a cast as conservative treatment.

The studies of Freeman25, ‘ , Gr#{248}nmark et

al.33, van Moppens and van den Hoogenband76, Korkala et

al.48, and M#{248}bler-Larsen et al.58 also had a third comparison

group, in which the injury was treated by strapping and

early controlled mobilization (functional treatment).

The duration of immobilization in a cast for patientswho had operative treatment and those who did not varied

among the studies and ranged from three to six weeks.

However, in each study (except the one by Prins61) the

duration was the same for patients who had been operated

on and for those who did not have an operation. In the study

by Prins6’ , the duration of immobilization in a cast was three

weeks for patients who were operated on but six weeks for

patients who were conservatively treated.

Seven studiesH253348SS7276 included a group of patients

who were treated with bandage or tape support only (func-

tional treatment); in these patients, early controlled mobi-

lization with full weight-bearing was allowed, within the

limits of pain, immediately after the injury. in the other two

groups that had immobilization in a cast, the time to weight-

bearing varied, among the studies, from zero to five weeks.

Most often, full weight-bearing was allowed within the first

two weeks.

Size of the Sample

The number of patients in each of the twelve studies

ranged from twenty-four to 28 1 . Only two studies’7’25 had

fewer than fifty participants, and the average was 125.

TREATMENT FOR ACUTE TEARS OF THE LATERAL LIGAMENTS OF THE ANKLE 307

VOL. 73-A, NO. 2, FEBRUARY 1991

Operative Technique

In all twelve studies, a very similar operative techniquewas used: primary suture of the ruptured ligaments. Bro-

1 used continuous sutures; in the other studies, therepair was performed with interrupted stitches and absorb-

able sutures. A detailed description of the operative tech-

nique was given by Prins6’ and by van Moppens and vanden Hoogenband76.

Physiotherapy

In six studies”�’7�24�25�33.58 specific physiotherapy was

prescribed after the period of immobilization. It included

various modes of treatment involving supervised mobili-

zation of the ankle; peroneab-muscbe, toe-raise, and toe-jump exercises; proprioceptive training; massage; and ultra-

short wave therapy. In each study, the rehabilitation pro-

gram was the same for each group. Two studies�’72 reportedthat no organized physical therapy was given, and in the

other fou?8’58’59’6’ it was not mentioned.

Duration of Follow-up and Number of Patients Followed

In all of the studies, follow-up consisted of normal

office visits at regular intervals after the injury. The latestfollow-up examination was six months after the injury in

three studies’7’�’6’ ; one year in five studies25’58’59’72’76; one

and one-half years in one study33; two years in two

studies24’48; and 3 . 8 years in one ‘ . The average du-

ration of follow-up was 1 .2 years, which we believe is long

enough to identify persistent mechanical instability but too

short to recognize late osteoarthrotic changes36.

The number of patients who were able to attend the

latest examination (the follow-up percentage) is critical

when the quality of a clinical orthopaedic trial is evaluated.

This value ranged from 63 to 100 per cent (average, 89 per

cent). In seven of the twelve studies, it exceeded 90 per

cent.

Follow-up Methods

All but three of the studies had subjective (question-

naire), clinical (physical examination), and radiographic

(stress radiographs) components of the follow-up protocol.In the work by Gr#{248}nmarket al.33, only results from mailed

questionnaires were presented. In the studies reported byBrostr#{246}m” and Niedermann et al.59, stress radiographs were

not made.

Radiographic follow-up evaluation of talar tilt and an-

terior drawer is of great importance when primary repair is

compared with conservative treatment, since the most im-

portant advantage of operative repair has been reported to

be improved mechanical stability of the ankle. This may,

in turn, bead to a decrease in late symptoms, such as giving-

way, pain, swelling, and stiffness.

When the foot is in the neutral position, the anteriordrawer test determines the integrity of the anterior tibiofib-

ular ligament primarily. Talar tilt primarily tests the cal-

caneofibular ligament when the foot is in that position, but

also the anterior tibiofibular ligament if the foot is in plantar

flexion53’�. The exact techniques used for testing anterior

drawer and talar tilt on stress radiographs varied among the

twelve studies, but within each study the same technique

was used for every patient.

Opinions vary regarding the value of the radiographic

talar-tilt test compared with the anterior drawer test. Tra-

ditionally, many have favored the talar tilt test’8’49’50’65, while

recently the anterior drawer test has been suggested to be

more reliable43. Some authors have concluded that the two

tests are complementary and that they should be used in

combination32’42’6’.

Statistical Analysis

Statistical analysis was adequately performed in eight

studies. In the other four’7’24’25’33, no statistical calculations

were given to support the conclusions.

Evaluation of Results

In general, according to the twelve studies, the resultsafter treatment of an acute grade-Ill sprain of the lateral

ligaments of the ankle were excellent. In most patients (75

to 100 per cent), irrespective of the therapy (repair and cast,

cast alone, or early controlled mobilization), the one-year

prognosis was excellent or good and fully acceptable, and

only a few patients had residual symptoms. Interestingly,

these over-all results were better than those reported in the

earlier studies7’35’52’73’74.

Furthermore, the twelve studies did not identify any

difference between the patients who had an isolated rupture

of the anterior tibiofibular ligament and those who had a

combined injury of the anterior tibiofibubar and calcaneo-

fibular ligaments. These findings may partially explain why,

in all retrospective, uncontrolled studies, the treatment that

is presented has led to fine results, and why such a contro-

versy about proper treatment can persist for years.

We selected nine outcomes by which to evaluate the

results of the studies: return to work or physical activity;

functional instability; pain, swelling, or stiffness with ac-

tivity; mobility of the ankle; atrophy of the muscles; return

to preinjury level of activity; reinjury; objective mechanicalstability of the ankle; and complications. For each outcome,

the five studies’7’24”�’59’6’ that had two treatment groups (re-

pair and cast and cast alone) were compared separately from

the six studies”25’33’48’58’76 that had three groups (repair and

cast, cast alone, and functional treatment). The twelfth

study72, comparing repair and immobilization in a cast with

functional treatment, was included in the latter comparison.

Return to Work or Physical Activity

Return to work or physical activity is an important

variable because of economic reasons. In addition, athletesand other physically active people appreciate a quick return

to training and competition.

Of the five studies that had two treatment groups, twoshowed that treatment in a cast alone was better in this

respect, with the time to return to activities averaging one

to two24 and four17 weeks earlier than after operative repair.

308 PEKKA KANNUS AND PER RENSTROM

ThE JOURNAL OF BONE AND JOINT SURGERY

Klein et ab.� found no difference, and Niedermann et al.59

did not report on this outcome. Prins6’ used different du-

rations of immobilization (three weeks after operation, but

six weeks when a cast was the only treatment), so his resultswere not used for comparison.

Of the seven studies that included patients who hadfunctional treatment, 25,58,76 reported the time between

injury and return to work or physical activity. The conclu-

sion in each of the four studies was that functional treatmentwas superior to the other two modalities in this respect;

return to activity was two to four times faster after functional

treatment than after operation or immobilization in a cast.

Treatment with a plaster cast alone was also found to be

slightly better than operative treatment and a cast.

Functional instability (Feeling of Giving-Way)

The term functional instability of the ankle was first

used by Freeman et al.26 to designate the disability to which

patients refer when they say that the foot tends to “give

away’ ‘ . This phenomenon has been reported to occur after

15 to 60 per cent of injuries to the lateral ligaments of the

ankle5’7’26’35’52’70’7375, and it seems to be independent of the

grade of the initial injury70’76.

The exact pathomechanics of this symptom are not

clear. It has been shown repeatedly’5’24’26’�’62’63’7476 that,

after an acute injury of the ankle, there is no correlation

between proved mechanical instability (radiographic talar

tilt and anterior drawer tests) and patients’ complaints of

functional instability (giving-way, pain, and swelling).

Freeman et al.26 suggested that functional instability of the

ankle is usually due to motor incoordination secondary to

a disorder of proprioception. In their prospective, random-

ized trial, they demonstrated that the incidence of this prob-lem can be reduced substantially by a treatment protocol

involving coordination exercises done on an ankle tilt-board.

Recently, this finding was confirmed by Tropp75 and by

Gauffin et al.29.

Other factors, such as formation of adhesions leadingto decreased mobility of the ankle (especially dorsiflexion),

weakness of the peroneal muscles, and chronic sprain of

the tibiofibubar ligament�’6’54’73, may also cause functional

instability. However, the specific robe of each of these fac-tors is, as yet, poorly defined.

Of the five studies that had two treatment groups, thefrequency of persistent functional instability was reported

in four. In two studies�’59, no difference was found between

the groups, with an average of 93 and 75 per cent of asymp-

tomatic patients. Evans et al.24 found that treatment in a

cast alone was better: 8 per cent of the patients who hadonly a cast had functional instability, compared with 26 per

cent of the patients who had repair and a cast. However,

Prins6’ found that, six months after the injury, 92 per cent

of the patients who had been treated with a cast only had a

fear of giving-way of the ankle; in patients who had oper-

ative repair, only 22 per cent had functional instability.

Of the seven studies that also included a functionaltreatment group, the frequency of late functional instability

was reported in five. In two studies”47, operative treatment

gave the best results (fewer than 10 per cent of the patients

had giving-way, compared with 18 to 50 per cent in the

other groups). In two studies58’76, functional treatment pro-

duced the best results (14 to 22 per cent of the patients had

functional instability, compared with 24 to 42 per cent in

the other groups). In the fifth study, by Freeman25, no dif-

ference could be identified among the groups.

In summary, three studies found no differences amongthe treatment groups, three found that there was less func-

tional instability after operative repair than after other treat-

ments, and three found that conservative treatment (cast or

functional treatment) was better than operative repair. We

concluded that no one treatment method seemed to reliably

minimize the chances of late functional instability.

Pain, Swelling, or Stiffness with Activity

Pain, swelling, and stiffness correlate closely with

functional instability, and quite often the two outcomes oc-

cur together.In four’7’24’�’59 of the five studies that had two treatment

groups, there was no difference in this outcome between

the group that had operative repair and a cast and the group

that had treatment with a cast alone. The incidence of these

symptoms ranged from 10 to 27 per cent. Prins6’ , again,

found completely different results. Pain occurred in only 7

per cent of the patients who had an operation but in 63 per

cent of the patients who had only a cast. Swelling persistedin 2 per cent of the patients who were operated on and in

29 per cent of those who were treated with only a cast.

Information regarding pain, swelling, and stiffness was

available in four of the seven studies that had a functional

treatment group. Freeman25 and M#{248}lber-Larsen et al.58 found

that functional treatment was better than a cast alone, and

the worst results were after operative treatment. Van Mop-

pens and van den Hoogenband76 reported no differences,

and Gr#{248}nmark et al.33 found that operative repair was betterthan the other forms of treatment.

In summary, these studies failed to demonstrate anydifferences among the treatment groups regarding long-term

pain, swelling, and stiffness, and recommendations cannot

be made regarding the optimum treatment to minimize these

problems.

Mobility of the Ankle

Restricted mobility of the ankle, especially in dorsi-

flexion, has been cited as one reason for persistent com-

plaints by patients5’6. Mobility of the ankle was measured

at the follow-up examination in three of the five studies that

had two treatment groups. Evans et al.24 noted that mobility

of the ankle was normal in 80 per cent of patients who had

conservative treatment but in only 48 per cent of patients

who had operative treatment. Niedermann et al.59 and Prins6’

found no differences between the two groups.

Mobility of the ankle was measured in 7276 of

the seven studies that included three therapy groups. In all

of these studies, functional treatment was superior to the

TREATMENT FOR ACUTE TEARS OF THE LATERAL LIGAMENTS OF THE ANKLE 309

VOL. 73-A, NO. 2. FEBRUARY 1991

other two methods for achievement of a full range of motion

earlier after the injury. However, after one year, there were

no differences.

Atrophy of the Muscles

Atrophy of the muscles in the calf was evaluated in

only two studies5976. In both, the circumferences of the

uninjured and injured sides were compared. Niedermann et

al.59 found no difference in this outcome, one year after the

injury, between patients who had operative treatment and

those who had only a cast. Van Moppens and van den

Hoogenband76 observed that, after nine weeks, patients who

were operated on or had immobilization in a cast had a

substantially higher rate of atrophy of the muscles of the

calf than did patients who had functional treatment (22 and

18 per cent compared with 4 per cent). After six months,

however, this difference did not persist.

Return to Preinjury Level of Activity

This criterion has been used very frequently in studies

of sprains of the ankle. Generally, at the final follow-up

examination, the researcher combines the subjective, func-

tional, and clinical data to determine an over-all result. It

is a very subjective parameter and, therefore, is sensitive

to bias. Additionally, one researcher may emphasize some

part of the evaluation more than others.

All five studies comparing two treatment methods gave

information on patients who returned to preinjury status. In

three studies’7’�’59 no difference was found between the

groups, and 62 to 8 1 per cent of the patients had recovered

completely. Evans et al.24 concluded that a cast alone was

better than operation (59 compared with 37 per cent). Prins6’

found no difference between the groups if return to everyday

activities was the criterion (98 per cent for both groups),

but operative repair had a considerable advantage if return

to sports was the criterion (77 compared with 29 per cent).

In the seven studies comparing three treatment groups,

all reported the number of patients who had returned to

preinjury status by the time of the latest follow-up exami-

nation. In three of the studies25’58’76, functional treatment

was found to be superior to operation or immobilization in

a cast. In the study by M#{248}lber-Larsen et al.58, complete

recovery occurred in 82 per cent of the patients in the func-

tional-treatment group, 65 per cent in the cast group, and

56 per cent in the operative-repair group. In the study by

van Moppens and van den Hoogenband76, the same per-

centages of return to preinjury status were 100, 98, and 95

per cent, and in the study by Freeman25, the rates were 58,

53 , and 25 per cent. In the study by ‘ , function

was fully restored in 92 per cent of the patients who were

operated on, in 82 per cent of those who had functional

treatment, and in 79 per cent of those who had immobibi-

zation in a cast. Gr#{248}nmark et al.33 reported similar results

of 97, 77, and 67 per cent. In two studies48’72, no difference

was found among the groups.

In summary, in five studies, no differences were iden-

tified; in four, conservative treatment was found to be better

than operative repair; and in three, operative treatment pro-

duced better results. Thus, we cannot recommend one mode

of treatment over the others if final restoration to the prein-

jury level of activity is used as the only criterion.

However, a clear advantage for treatment with strap-

ping and early controlled mobilization (functional treatment)

was present in most of these studies, if the time to the

absence of symptoms was also used as a criterion. This

finding was best demonstrated by van Moppens and van den

Hoogenband76, who carefully followed their patients nine,

twelve, twenty-four, and fifty-two weeks after the injury.

At nine weeks, 68 per cent ofthe patients who had functionaltreatment had been restored to the preinjury level, compared

with 7 per cent of those who were operated on and 13 per

cent of those who had only a cast. At twelve weeks, func-

tionab treatment still represented a considerable advantage

(81 , 36, and 7 per cent), and even at twenty-four weeks

there were differences (98, 76, and 88 per cent).

Reinjury

The number of patients who had had one or more

reinjuries may be a direct reflection of the mechanical in-

stability of the ankle. Of the five studies in which operative

repair and treatment with a cast were compared, four re-

ported the rate of reinjury during the period of follow-up.

In three studies24’�’59, there was no difference between the

treatment groups; the incidence ranged from 4 to 28 per

cent. Again, Prins6’ found that operation was superior: none

of the patients who had operative repair had a reinjury, but

19 per cent of those in the group that had only a cast had

a reinjury. The frequency of reinjury was evaluated in

four�’48’72’76 of the seven studies that had three treatment

groups. There were no differences among the groups, with

the incidence of reinjury ranging from 0 to 25 per cent.

Objective Mechanical Stability of the Ankle

Objective mechanical stability of the ankle is the most

important variable when the results of operative and con-

servative treatment are compared, since improved mechan-

icab stability after primary repair has been the main argument

for operation. Mechanical instability has been claimed to

be an important factor in the development of bate symptoms,

such as the feeling of giving-way, recurrent sprains, swell-

ing, tenderness, and pain. Mechanical stability of the ankle

can be measured objectively only with evaluations of tabar

tilt and anterior drawer on stress radiographs. Therefore,

only the evaluation of these examinations is reported here.

Of the five studies comparing operative treatment with

immobilization in a cast, three reported the results of ex-

amination with stress radiographs at the most recent follow-

up examination. Evans et al.24 and Klein et al.� observed

no difference between the two groups, but Prins6’ found that

operation gave better results: talar tilt was significantly less

in the ankles that had been repaired operatively (mean, 3.4degrees) than in those that had been immobilized in a cast

(mean, 9.9 degrees). No difference in anterior drawer was

noted between the two groups.

310 PEKKA KANNUS AND PER RENSTROM

ThE JOURNAL OF BONE AND JOINT SURGERY

Tabar tilt or anterior drawer, or both, was measured

radiographically at follow-up in five of the seven studies

evaluating three treatment groups. In four studies25’485876,

no substantial differences were found among patients who

had had an operation, immobilization in a cast, or functional

treatment, but Sommer and Arza72 concluded that functional

treatment was better than operation. The initial mean talar

tilt was 18 degrees in the functional-treatment group, and

at the one-year follow-up examination, it had decreased to

6 degrees (average improvement, 14 degrees). In the pa-

tients who were operated on, the initial mean talar tilt was

15 degrees, and at one-year follow-up examination, it was

6 degrees (average improvement, 9 degrees). The initial and

follow-up values for anterior drawer were eight and six

millimeters in the group that had functional treatment and

seven and six millimeters in the group that had an operation.

With mechanical stability as the criterion, operation,

immobilization in a cast, and functional treatment seem to

give equal, mostly excellent, results. Therefore, improved

mechanical stability alone does not seem to be a reason to

justify operative repair of acute tears of the lateral ligament

of the ankle.

Furthermore, three24”�’76 of the studies, as well as pre-

vious investigations’5’2662637475, suggest strongly that pure

mechanical instability of the ankle after an acute sprain of

the ankle is not an appreciable independent reason for the

development of late symptoms. In this respect, the theory

of Freeman et al.26 that motor incoordination and weakness

of the peroneab muscles are consequences of a disorder of

proprioception seems more appropriate. Mechanical insta-

bibity, a proprioceptive deficit, and weakness ofthe peroneal

muscles may occur simultaneously in the same patient (par-

ticularly in the presence of gross mechanical instability),

making it very difficult to identify the specific cause of

persistent functional instability.

Complications

To justify its use as a suitable choice of treatment for

injuries to the ligaments of the ankle, the optimum therapy

should be free of complications.

Of the five studies that had two treatment groups, all

reported the rate and type of complications. All complica-

tions but one occurred in groups that were treated opera-

tively. Niedermann et al.59 reported that, in the patients who

were operated on, the rate of infection of the wound was 4

per cent; the incidence of dysesthesias, 7 per cent; and the

rate of ‘ ‘ neuroma-like tenderness of the scar’ ‘ , 9 per cent.

Of the fifty patients in the operative-repair group in the studyby Evans et al.24, one had a pulmonary embolus, one had

Sudeck atrophy, six had a sensory deficit about the ankle,

and two had increased sensitivity of the skin over the scar.

Evans et ab. were the only authors to report a complication

(deep venous thrombosis of the calf) in the group that had

only immobilization in a cast. Clark et al.’7 reported that

manipulation of the ankle under anesthesia was needed four

months after one operative repair. Klein et al.� noted hy-

persensitivity of the scar in 19 per cent of the patients who

had an operation. Finally, Prins6’ reported three infections

of the wound and two paresthesias on the lateral side of the

foot.

Of the seven studies that had three treatment groups,

four reported complications, all but two of which occurred

in the operatively treated patients. Van Moppens and van

den Hoogenband76 reported that three patients had pain in

the area of the scar and one had hyperesthesia of the scar.

Korkala et al.48 observed five cases of deep venous throm-

bosis of the calf: two in the group that had a cast and three

in the group that had an operation. Gr#{248}nmark et al.33 noted

one deep venous thrombosis of the calf in an operatively

treated patient. Finally, ‘ reported that one patient

who had operative treatment had superficial necrosis of the

skin adjacent to the operative wound that necessitated skin-

grafting. In addition, seven patients who had operative re-

pair had a neuroma in the scar, and five had reduced sen-

sibility in the area.

Thus, with complications as the criterion, functional

treament is the safest choice (no complications in these

twelve studies). Immobilization in a cast is very safe as

webb. Operative treatment may, on occasion, produce Se-

rious complications.

Comparison of the Final Conclusions of Each Study

In each study, the authors reached a final conclusion

about the proper treatment of acute grade-Ill sprains of the

lateral ligaments of the ankle.

Of the five studies in which treatment with an operation

and a cast was compared with treatment with a cast alone,

the authors of three24�’59 concluded that conservative treat-

ment (cast alone) is the method of choice, even though they

indicated that early mobilization might give better results.

Clark et � also recommended conservative treatment,

with one exception - a young athlete who had a severe

tear and a talar tilt of more than 15 degrees - for whom

they recommended operative treatment. Prins6’ recom-

mended operative repair as the basic method of treatment.

In all seven studies that had three treatment groups,

the authors recommended functional treatment as the pri-

mary choice. Four�5’58’72’76 recommended functional treat-

ment without any reservations, and thre&”33’44 cited one

reservation: the young, active athlete, for whom primary

operative repair should be considered.

Conclusions

The treatment of acute complete (grade-Ill) tears of the

lateral ligaments of the ankle has generated much contro-

versy in the medical literature because the bong-term prog-

nosis is excellent or good in most patients, regardless of the

treatment (operative repair and cast, cast alone, or early

controlled mobilization). Perhaps, therefore, retrospective,

uncontrolled studies have been able to show fine results

whatever the actual treatment was.

After a critical review of these twelve studies, it is not

difficult to select functional treatment as the treatment of

choice for acute complete tears of the lateral ligaments of

TREATMENT FOR ACUTE TEARS OF THE LATERAL LIGAMENTS OF THE ANKLE 311

VOL. 73-A, NO. 2, FEBRUARY 1991

the ankle. Functional treatment includes only a short period

of protection by tape, bandage, or a brace, and allows early

weight-bearing. Range-of-motion exercises, as well as neu-

romuscular training of the ankle, should begin early. This

program clearly provides the quickest recovery to a full

range of motion and return to work and physical activity.

It does not, however, compromise the bate mechanical sta-

bility of the ankle more than the other treatments, and it

does not produce more bate symptoms (giving-way, pain,

swelling, stiffness, or muscular weakness) than operation

and immobilization in a cast or a cast alone. In addition,

functional treatment seems to be virtually free from com-

plications, while after the other methods of treatment, es-

pecialby operation, serious complications sometimes occur.

There are other reasons to consider functional treatment

as a method of choice. First, as has been reported by many

authors2 12. 3. I6,22.23,3� .43-45,67,68,7I , secondary operative recon-

struction or delayed repair of the ruptured ligaments of the

ankle can be performed years after the injury if necessary,

with good results that are fully comparable with those of

primary repair. Therefore, even competitive athletes may

be treated functionally at first, with the realization that 10

to 20 per cent may need elective secondary repair. Second,

functional treatment saves the patient from additional trauma

to the tissues and complications that are caused by operation.

Finally, the costs of the different treatments must be con-

sidered. Appreciation of the cost-benefit ratio for all types

of medical treatment has become extremely important in

modern health-care systems with limited economic re-

sources. In the treatment of sprains of the lateral ligaments

of the ankle, functional treatment can mean enormous eco-

nomic savings compared with an operation.

There are, however, some situations to which these

twelve studies did not give a specific answer, and when

operation should still be considered in the acute phase. Such

situations include large avulsions of bone and severe liga-

mentous damage on both the medial and lateral sides of the

ankle, indicating a major injury of the joint. An operation

may also be appropriate when the injury is severe and re-

current. Finally, because in none of these twelve studies

were the patients followed for more than four years, no

conclusion can be drawn regarding the effect of the three

methods of treatment on the late development of osteoar-

throsis of the ankle joint.

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