Ankle Sprain

By admin On Jan 3, 2024

Ovid: 5-Minute Orthopaedic Consult

Editors: Frassica, Frank J.; Sponseller, Paul D.; Wilckens, John H.

Title: 5-Minute Orthopaedic Consult, 2nd Edition

> Table of Contents > Ankle Sprain

Ankle Sprain

Dennis E. Kramer MD

Basics

Description

Acute sprains of the lateral ligaments about the ankle are the most common injury in sports (1) and also occur commonly in the general population.
Most commonly a partial tear or complete rupture of the ATFL occurs (2).
- More severe injuries include the CFL (2).
- Lateral ankle sprain results from an inversion mechanism.
Classification (3):
- Grade I: Partial tear of the ligaments
- Grade II: Partial to complete tear of the ATFL, partial tear of the CFL
- Grade III: Complete rupture of the ATFL and CFL
Ankle sprains cause sequential disruption of:
- Anterolateral joint capsule
- ATFL
- CFL
Primary static restraints to ankle inversion injury:
- ATFL:
  - Most commonly injured ankle ligament
  - Primary restraint to inversion with ankle plantarflexed
  - Torn in inversion, plantarflexion, and internal rotation
- CFL:
  - Stabilizes ankle and subtalar joints
  - Tears in inversion with ankle neutral or dorsiflexed
Primary dynamic restraints:
- Peroneal tendons

Epidemiology

Incidence

In the United States, ~27,000 of these injuries occur every day (4).
Most common athletic injury (1)

Risk Factors

Athletes
Dancers
Children with congenital tarsal coalition
Cavovarus foot alignment

Etiology

The injury results from inversion of the foot with the
ankle in varying degrees of plantarflexion when weight is placed on the
ankle.

Diagnosis

Signs and Symptoms

Pain, tenderness, and swelling over the lateral aspect of the ankle
Often difficult to bear weight on extremity

History

Mechanism of injury causing sprain:
- Inversion in plantarflexion: ATFL injury
- Inversion in dorsiflexion: CFL injury

Physical Exam

Tenderness and swelling are noted along
the lateral aspect of the ankle inferior and anterior to the tip of the
lateral malleolus.
Perform manual strength testing of muscle groups, including the peroneal tendons.
Assess the neurovascular status of the
limb, including the superficial peroneal nerve that can sustain a
stretching injury with inversion sprain.
Assess the ligament stability of the ankle.
- Compare with the uninjured ankle.
- Anterior drawer test:
  - Evaluates ATFL stability
  - Holding the distal tibia firmly with one
    hand, place the other hand around the heel and displace the hindfoot
    anteriorly with the ankle in a neutral position.
- Inversion tilt test:
  - Evaluates CFL stability
  - Position ankle in neutral dorsiflexion.
  - Stabilize distal tibia with 1 hand and apply inversion force to hindfoot with other hand.

Tests

Imaging

AP, lateral, and mortise radiographic views of the ankle are obtained.
- Rule out fracture, OCD of talus, or arthritic changes.
CT is indicated if occult fracture or tarsal coalition is suspected.
MRI:
- Rarely needed for acute ankle sprains
- Can be indicated if concomitant tendon tear is suspected

Differential Diagnosis (5)

Fibular fracture
Osteochondral fracture of the talar dome
Peroneal tendon subluxation
Congenital tarsal coalition
Talar fracture
Calcaneal fracture

Treatment

General Measures (1,4)

RICE protocol
Partial weightbearing with crutches in the acute phase (first 3–7 days), which is advanced as tolerated to full weightbearing
Stirrup ankle brace to facilitate early ambulation
NSAIDs may help with pain.
Gentle active ROM as tolerated is advised.
For severe sprains, consider a formal strengthening and proprioception retraining program with physical therapy (4).
Activity modification (rest, sports restriction) until strength returns

Special Therapy

Physical Therapy

ROM, strengthening exercises, and proprioceptive retraining are indicated (4).

P.25

Medication (Drugs)

First Line

NSAIDs and analgesics can be used for severe sprains, but they usually are not necessary.

Surgery

Surgical repair of acute ankle ligament tear is rarely indicated (4).
- Primary repair of ATFL and CFL (6)
Surgery may be indicated for patients with recurrent instability.
- In such patients, repair of the lateral
  ankle ligaments or reconstruction with part of the peroneus brevis
  tendon usually is successful.

Follow-up

Prognosis

The prognosis, which depends on injury severity, is excellent for most patients.

Complications

OCD
Recurrent sprains

Patient Monitoring

Patients should show full strength and ROM before returning to sports.
Functional bracing or taping during return to athletics may help prevent recurrence.

References

1. Clanton
TO, Schon LC. Athletic injuries to the soft tissues of the foot and
ankle. In: Mann RA, Coughlin MJ, eds. Surgery of the Foot and Ankle,
6th ed. St. Louis: Mosby-Year Book Inc, 1993:1095–1224.

2. Brostrom L. Sprained ankles. I. Anatomic lesions in recent sprains. Acta Chir Scand 1964;128: 483–495.

3. Leach
RE, Schepsis AA. Acute injuries to ligaments of the ankle. In: Evarts
CM, ed. Surgery of the Musculoskeletal System, 2nd ed. New
York:Churchill Livingstone, 1990:3887–3913.

4. 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;73A:305–312.

5. Renstrom PAFH. Persistently painful sprained ankle. J Am Acad Orthop Surg 1994;2:270–280.

6. Brostrom L. Sprained ankles. V. Treatment and prognosis in recent ligament ruptures. Acta Chir Scand 1966;132:537–550.

Additional Reading

Chabra A, Katolik LI, Pavlovich R, et al. Sports medicine. Section 3. Leg, foot, and ankle. In: Miller MD, ed. Review of Orthopaedics, 4th ed. Philadelphia: WB Saunders Co, 2004:228–231.

Thacker SB, Stroup DF, Branche CM, et al. The prevention of ankle sprains in sports. A systematic review of the literature. Am J Sports Med 1999;27:753–760.

Miscellaneous

Codes

ICD9-CM

845.0 Ankle sprain

Patient Teaching

Activity

An appropriate return to activity plan is determined based on the severity of the ankle sprain.

Prevention

Proprioceptive training has been shown to decrease recurrent sprains.

FAQ

Q: Which ligaments are involved and in what sequence in a lateral ankle sprain?

A: A lateral ankle sprain injures the following, in order: anterolateral joint capsule, ATFL, and occasionally the CFL.

Q: What condition must be ruled out in an adolescent patient with a rigid flatfoot and recurrent ankle sprains?

A: Tarsal coalition.

Which ligament provides primary static restraint to inversion injury with the ankle plantarflexed?

ATFL.

What are appropriate initial treatments for acute ankle sprain?

RICE protocol, stirrup brace, early ambulation, and ROM exercises.