Foot and ankle rehabilitation success hinges on screening accuracy

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Biomechanics Magazine June 2006

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Foot and ankle rehabilitation success hinges on screening accuracy

The challenge of treating athletes is to return them to sports

activity quickly without risking disability.

By: Saluta, MD, and A. Nunley, MD

Traumatic injuries of the foot and ankle occur frequently in sports

activity. In a review of injuries seen in a multispecialty sports

clinic, 25% of 12,681 injuries that occurred in the 19 sports cited

as most popular involved the foot and ankle.1 In addition, an

estimated 20% to 35% of total time lost to injury in running and

jumping sports can be attributed to ankle injuries.2

Practitioners who treat athletes with traumatic injuries of the foot

and ankle should keep in mind some key points. Proper evaluation is

important. Knowledge of when to order special imaging studies, such

as stress x-rays or an MRI, should be incorporated into the

diagnostic armamentarium. Cognizance of the more serious diagnoses is

especially important. Determining which problems can be managed in

the office and which ones require immediate referral to an orthopedic

surgeon for operative management is prudent.

Early treatment makes a crucial difference to a patient's chances of

successful surgery for acute fractures and ligament tears. Reviewing

some of the less common problems, such as a navicular stress fracture

or a Lisfranc sprain, is beneficial; if they are missed, significant

disability may result. Treating athletes is more difficult than

treating persons in the general population-the special challenge is

to return the athlete to sports activity quickly without risking

disability.

Ankle sprains

Diagnosis. These are the most common foot and ankle injuries seen in

athletes. Studies in Scandinavia have shown that ankle sprains

account for up to 21% of sports-related injuries.3 The mechanism

usually is forced inversion of the ankle, which tears one or more of

the lateral ankle ligaments. These ligaments, which provide lateral

stability to the ankle, are the anterior talofibular ligament (ATFL),

calcaneofibular ligament (CFL), and posterior talofibular ligament

(PTFL).

Injuries can be classified in three grades. Grade 1 sprains involve a

stretch or tear of the ATFL with no instability of the joint, grade 2

sprains consist of a complete tear of the ATFL with a partial or

complete tear of the CFL, and grade 3 sprains include complete tears

of both the ATFL and the CFL.4

Initial evaluation consists of a physical examination, which should

include palpation over the fibular origin of the ATFL and the

calcaneal insertion of the CFL. Swelling anterior or inferior to the

malleolus should be differentiated from supramalleolar swelling,

which may indicate fracture or syndesmotic injury.

Patient assessment includes the anterior drawer test, which involves

subluxation of the talus anterior to the tibia with the knee bent and

the ankle plantar-flexed. Measuring anterior translation, this test

is used to judge the integrity of the ATFL (normal value, 2 to 9 mm).

The talar tilt test examines the integrity of the CFL. The examiner

inverts the heel and checks for signs of instability, such as a soft

end point. A positive talar tilt test result indicates a grade 3

sprain. This test is best performed under fluoroscopy with comparison

to the contralateral side.

For simple sprains, plain x-rays are frequently obtained but usually

not indicated. The Ottawa Ankle Rules were developed to identify

patients who require x-rays in the acute setting. According to the

rules, if a patient demonstrates tenderness at the tip of either

malleolus, an inability to walk four steps, or pain at the base of

the fifth metatarsal, then appropriate foot and ankle x-rays should

be ordered.

Stress radiographs and MR images usually are not needed in the acute

setting, but they may help in the diagnosis of chronic ankle pain. We

recommend MRI for acute injuries with medial ecchymosis and for

chronic sprains that are still symptomatic four months after injury.

MRI is also helpful in the diagnosis of injuries or conditions that

may mimic ankle sprains, such as syndesmotic ligament tears,

osteochondral lesions of the talus, occult stress fractures,

synovitis, adhesions, intra-articular loose bodies, chronic

instability, anterolateral impingement, and peroneal tendon

pathology.

Treatment. Functional rehabilitation is our first-line treatment for

a patient with a simple ankle sprain. Treatment modalities (e.g.,

long-term immobilization and surgical management) have resulted in

slower return to activity, higher cost, and more complications

without better effectiveness.3

Our initial management includes RICE (rest, ice, compression, and

elevation) and anti-inflammatory drugs for pain control; use of

crutches for grade 1 and 2 injuries is discouraged. A short period of

immobilization and protective bracing is implemented next. Then the

patient is started on early active range of motion exercises,

proprioception training, peroneal strengthening, and sport-specific

exercises. The athlete may return to sports activity after the pain

has resolved and ankle strength is equal to that of the opposite

side.

At our institution, the majority of grade 1 sprains are diagnosed and

managed by trainers; referrals to orthopedists for these injuries are

rare. Return to activity usually occurs after three to five days for

grade 1 sprains and after one to three weeks for grade 2 sprains; it

takes longer for grade 3 sprains, and ankle protection may be

required for up to six months.

Referral to an orthopedic surgeon is indicated in the acute phase for

injuries with severe laxity, fractured bone, or medial ecchymosis. In

10% to 20% of athletes, initial treatment is unsuccessful and

orthopedic referral should be considered. Surgical procedures for

chronic instability, such as the Brostrom-Gould repair, have had

excellent results.5

Syndesmotic injuries

Diagnosis. There are several differences between simple lateral ankle

sprains and distal syndesmotic, or high ankle, sprains. Syndesmotic

injuries are less common and more easily misdiagnosed, and patients

take much longer to return to sports activity.

The ligaments that make up the distal syndesmosis are the anterior

inferior tibiofibular ligament, the posterior inferior tibiofibular

ligament, and the interosseous ligaments. Syndesmotic injuries occur

most frequently in collision sports.6 The exact mechanism is not

known and has not yet been reproduced in any cadaveric study. These

injuries are referred to as high ankle sprains because the ligament

damage is above the true ankle joint.

On physical examination, swelling may be present proximal to the

lateral malleolus. Results of the talar tilt and anterior drawer

tests are normal.

The squeeze test is performed by applying pressure at the patient's

midcalf to compress the fibula and tibia together; in an abnormal

test result, ankle pain at the syndesmosis is elicited. The external

rotation test is performed by externally rotating the foot with the

knee held at 90degrees of flexion; in an abnormal test result, pain

is elicited in the distal syndesmosis.

If a syndesmotic injury is suspected, we recommend ordering

anteroposterior, mortise, and lateral ankle x-ray views, as well as

an external rotation stress view. MRI can also help in making this

diagnosis.

Treatment. Syndesmotic injuries may be divided into three types. Type

1 injuries involve signs of syndesmotic sprain with normal x-ray

findings. They may be managed with functional rehabilitation similar

to the protocol used for simple sprains.

A type 2 injury is demonstrated by a tibiofibular clear space greater

than 6 mm measured 1 mm above the joint, as seen in a stress x-ray

view. Treatment consists of nonweight-bearing in a short leg cast for

four weeks followed by weight-bearing in an immobilization boot for

four more weeks.

Diagnosis of a type 3 injury is made by frank diastasis on the

nonstress radiographs; immediate referral to an orthopedic surgeon

for surgical stabilization is required.

Return to play for type 1 and 2 injuries averages eight to 12 weeks-

twice as long as with a severe lateral ankle sprain.7,8

Midfoot sprains

Diagnosis. Midfoot, or Lisfranc, sprains usually are caused by the

sudden rotation of a planted foot or an axial load placed on a

plantar-flexed foot. The classic mechanism involves a football player

whose foot is planted with the toes extended and ankle plantar-

flexed. Another player falls and places an axial load directly on the

heel.

Strong ligaments connect the second through fifth metatarsal bases.

Because the base of the second metatarsal is recessed in relation to

the first, no ligament connects these metatarsal bases. The Lisfranc

ligament attaches the base of the second metatarsal with the medial

cuneiform and secures this articulation, which acts as the keystone

to the tarsometatarsal joint complex. A high index of suspicion is

needed because signs of this ligament injury may be subtle in

athletes.

On physical examination, the patient may exhibit mild swelling, pain

with weight-bearing, and an inability to perform a single heel rise

or to run. Look for tenderness along the metatarsal bases, especially

between the first and second bases. Severe subluxation or dislocation

of the joint may manifest as a midtarsal prominence on the dorsum of

the foot. Passive motion of the joint in any direction, including

side-to-side compression of the midfoot, may elicit pain.

AP, lateral, and oblique weight-bearing x-ray views of the foot

should be obtained for any athlete who has midfoot pain. Stress views

are accomplished by weight-bearing or passive abduction of the

forefoot relative to the midfoot. Look for an avulsed flake of bone

at the base of the second metatarsal or diastasis between the medial

cuneiform and the second metatarsal. In addition, look for

compression fractures of the cuboid and cuneiforms, which may also

accompany this injury.

A bone scan may yield a diagnosis of the joints involved; we have

found this very helpful.9 An MRI is rarely needed and is indicated

only for equivocal injuries.

Treatment. Sprains that have no diastasis on plain or stress x-rays

may be managed with anti-inflammatories and RICE. We recommend

nonweight-bearing for four to six weeks followed by progressive

weight-bearing in a short leg walking cast for four to six more

weeks. However, we strongly recommend referring all patients with

Lisfranc sprains to an orthopedic surgeon. An examination conducted

under anesthesia may be needed to make the diagnosis, especially to

accurately determine unstable injuries.

Sprains that involve diastasis on either plain or stress x-rays

require immediate surgical evaluation. Unstable injuries may progress

to partial or total dislocation of the entire tarsometatarsal joint

complex. Return to play is much longer than with a simple ankle

sprain (possibly four to six months). On return to play, we recommend

that the athlete wear stiff-soled shoes with an orthosis. The athlete

should be counseled that even after adequate treatment, low-grade

midfoot pain may persist for years.

Base of the fifth metatarsal fractures

Diagnosis and treatment. The fracture is the best known

proximal fifth metatarsal fracture, but avulsion fractures and

diaphyseal stress fractures should also be recognized. On physical

examination, palpation elicits tenderness at the proximal fifth

metatarsal. AP, oblique, and lateral x-ray views of the foot should

be ordered.

In avulsion injuries, the fracture fragment is connected to the

lateral plantar aponeurosis and usually is detached by a strong

inversion force. Most of these fractures are nondisplaced; they may

be managed symptomatically with weight-bearing in a stiff-soled shoe

for three to four weeks. The fracture usually heals predictably with

no residual disability.

A true fracture occurs at the metaphyseal-diaphyseal junction;

it usually is attributed to lateral tensile stresses from forced

forefoot adduction. Often, the fracture is located 1.5 to 2 cm distal

to the base and has a high rate of delayed union and nonunion,

presumably because of compromised vasculature in this region.10

A recreational athlete who has a nondisplaced fracture may be treated

with nonweight-bearing in a short leg cast until there are clinical

signs of healing, usually after six to eight weeks. However, he or

she must be informed that nonsurgical treatment results in a longer

period before return to play because of multiple factors, which

include a delayed union rate of 25% to 66%, a nonunion rate of 7% to

28%,11 a long-term refracture rate of 33%,12 and a longer interval of

disuse atrophy.

Referral to an orthopedist for surgery is recommended for any athlete

who has a fracture. After the fracture has healed, we recommend

that athletes wear a protective orthosis.

The third type of fifth metatarsal base fracture, a diaphyseal stress

fracture, usually is associated with prodromal pain for several weeks

before there is radiographic evidence of injury. However, MRI may

reveal this injury before there is radiographic evidence.

Diaphyseal stress fractures respond poorly to conservative

management. Referral to an orthopedist for surgical stabilization is

recommended. Distal fractures of the fifth metatarsal do occur in

athletes but usually are nondisplaced and rarely require surgical

care.

Stress fractures

Diagnosis. These overuse injuries are often seen in athletes who

perform high-repetition, low-impact activities, such as running. The

fractures occur when normal bone is subjected to an aggregation of

subthreshold forces and the natural reparative response has been

overloaded. Causative factors to consider include unequal leg

lengths, varus knees, abnormal lower extremity alignment, cavus or

planus foot deformities, poorly cushioned shoes, hard running

surfaces and, in female athletes, hormonal imbalance.

Physical examination may reveal swelling and tenderness over the

bone, as well as an antalgic gait. Plain x-rays should be ordered of

the foot or ankle, depending on the area of suspicion. X-ray results

may be normal up to four weeks after symptoms manifest. If early

confirmation is needed, bone scan and MRI results are usually

abnormal in the first one or two days of symptoms.

Navicular stress fractures are more common than once thought,

although the incidence is probably still less than 1% of all stress

fractures of the lower extremity. Patients complain of pain in the

dorsum of the midfoot or in the medial arch.

On examination, pain in the navicular usually is elicited if the

patient stands on tiptoes. In addition to plain radiography, we

recommend CT scanning because the amount of fracture displacement can

be measured correctly and a bipartite navicular can be ruled out.

Treatment. For nondisplaced navicular fractures with minimal

comminution, we recommend nonweight-bearing in a short leg cast for

six weeks. A CT scan may confirm healing, and the athlete usually

returns to play six to 12 weeks after cast removal.

Displaced or comminuted fractures require surgical fixation. However,

we recommend that all patients with navicular stress fractures be

referred to an orthopedic surgeon for surgical evaluation. After

return to play, it is recommended that the athlete wear a semirigid

longitudinal arch support in athletic shoes.

Stress fractures of the distal fibula, calcaneus, and second to fifth

metatarsal shafts usually are managed nonoperatively. A reduction in

activity level allows most of these fractures to heal reliably; cast

immobilization is not usually necessary.

Patients with metatarsal stress fractures should wear a stiff-soled

shoe until symptoms resolve, usually after four to six weeks. A soft

heel cushion is recommended for calcaneal stress fractures until

resolution, usually six to eight weeks. With conservative treatment,

fibular stress fractures frequently resolve in four to six weeks. For

an athlete who has severe symptoms or is noncompliant, we recommend

weight-bearing in a short leg walking cast until symptoms resolve. At

this point, the athlete may make the transition to a stirrup brace.

Saluta, MD, is a foot and ankle fellow at Duke University

Medical Center in Durham, NC. A. Nunley, MD, is the J. Leonard

Goldner professor and chief of orthopedic surgery at the same

institution.

A version of this article appeared in the March issue of the Journal

of Musculoskeletal Medicine, a sister publication to BioMechanics.

References

1. Garrick JG. The frequency of injury, mechanism of injury, and

epidemiology of ankle sprains. Am J Sports Med 1977;5(6):241-242.

2. Mack RP. Ankle injuries in athletics. Clin Sports Med 1982;1(1):71-

84.

3. Kannus P, Renstrom P. Treatment for acute tears of the lateral

ligaments of the ankle. Operation, cast, or early controlled

mobilization. J Bone Joint Surg 1991;73-A(2):305-312.

4. Baxter DE. Traumatic injuries to the soft tissues of the foot and

ankle. In: Mann RA, ed. Surgery of the foot, 5th ed. St. Louis:

Mosby, 1986:456-472.

5. Keller M, Grossman J, Caron M, Mendicino RW. Lateral ankle

instability and the Brostrom-Gould procedure. J Foot Ankle Surg

1996;35(6):513-520.

6. Gerber JP, GN, Scoville CR, et al. Persistent disability

associated with ankle sprains: a prospective examination of an

athletic population. Foot Ankle 1998;19(10):653-660.

7. Arendt E, ed. Ankle soft tissue injuries. In: Orthopaedic

knowledge update: sports medicine 2. Rosemont, IL: American Academy

of Orthopaedic Surgeons, 1999:373-377.

8. Hopkinson WJ, St. Pierre P, JB, Wheeler JH. Syndesmosis

sprains of the ankle. Foot Ankle 1990;10(6):325-330.

9. Nunley JA, Vertullo CJ. Classification, investigation, and

management of midfoot sprains: Lisfranc injuries in the athlete. Am J

Sports Med 2002;30(6):871-878.

10. JW, Arnoczky SP, Hersh A. The intraosseous blood supply of

the fifth metatarsal: implications for proximal fracture healing.

Foot Ankle 1992;13(3):143-152.

11. Title CI, Katchis SD. Traumatic foot and ankle injuries in the

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Practice points

- Ankle sprains are the most common foot and ankle injuries seen in

athletes. The Ottawa Ankle Rules help identify patients who require x-

ray films in the acute setting. MRI helps in the diagnosis of

injuries or conditions that may mimic ankle sprains.

- Syndesmotic injuries are more easily misdiagnosed than lateral

ankle sprains. Anteroposterior, mortise, and lateral ankle x-ray

views are recommended if this injury is suspected.

- The diagnosis of midfoot sprains may be subtle in athletes. Look

for an avulsed flake of bone at the base of the second metatarsal and

compression fractures of the cuboid and cuneiforms.