Dr. Kevin Yip

Dr Kevin Yip
Orthopaedic Surgeon
MBBS(UK), FRCS(EDIN), FAM(SING), FHKCOS(ORTHO)

Featured on Channel NewsAsia

Ankle Sprain

Basics
Description
  • Acute sprains of the lateral ligaments about the ankle are the most common injury in sports and also occur commonly in the general population.
  • Most commonly a partial tear or complete rupture of the ATFL occurs.
    • More severe injuries include the CFL .
    • Lateral ankle sprain results from an inversion mechanism.
  • Classification :
    • 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.
  • Most common athletic injury
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
  • Fibular fracture
  • Osteochondral fracture of the talar dome
  • Peroneal tendon subluxation
  • Congenital tarsal coalition
  • Talar fracture
  • Calcaneal fracture
Treatment
General Measures   
  • RICE protocol
  • Partial weightbearing with crutches in the acute phase (first 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 .
  • Activity modification (rest, sports restriction) until strength returns
Special Therapy
Physical Therapy
ROM, strengthening exercises, and proprioceptive retraining are indicated .
 
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.
    • Primary repair of ATFL and CFL
  • 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.
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.
 
Q: Which ligament provides primary static restraint to inversion injury with the ankle plantarflexed?
ATFL.
 
Q: What are appropriate initial treatments for acute ankle sprain?
RICE protocol, stirrup brace, early ambulation, and ROM exercises.

1 comment to Ankle Sprain

  • Да, действительно. Я присоединяюсь ко всему выше сказанному. Можем пообщаться на эту тему….

    Lateral ankle sprain results from an inversion mechanism.

    Classification :

    Grade I: Partial tear […….