Lateral Ankle Sprain

A lateral ligament ankle sprain occurs when the ligaments outside the ankle are stretched beyond their limits. Injury to these ligaments causes pain and swelling in the ankle. Generally, most sprained lateral ligaments are minor and will improve with simple treatments.

Other Names

  • Ankle sprain
  • Rolled ankle
  • Inversion Ankle Injury
  • Lateral Ankle Sprains (LALS or LAS)
  • Low Ankle Sprain

Illustration of a lateral view of the ankle joint with ligaments, bones, and tendons labeled

  • General
    • The injury mechanism is characterized by a high-velocity inversion and internal rotation of the ankle/foot complex
    • Particularly prevalent in field and court sports
    • The vast majority will self resolve in 4-6 weeks, although some may persist for years

Causes

  • General
    • Occurs due to exaggerated, high force inversion and plantarflexion
    • This leads to stretching, tearing, or rupture of the lateral ankle ligaments
    • Typically in a sequential pattern depending on the severity
    • Starts with the anterior talofibular ligament (ATFL) followed by the calcaneofibular ligament (CFL) followed by the posterior talofibular ligament (PTFL)
  • First contact mechanism
    • Due to player-to-player contact with impact by an opponent on the medial aspect of the leg
    • Occurs just before or at foot strike, resulting in a laterally directed force across the ankle
    • This causes the player to land with the ankle in a vulnerable, inverted position
  • Second contact mechanism
    • Forced plantarflexion is where the injured player hit the opponent’s foot when attempting to shoot or clear the ball.

Associated Conditions

  • Chronic Ankle Instability
  • Ankle Osteoarthritis
  • Syndesmotic Sprain
  • Maisonneuve Fracture
  • Osteochondral Defect
  • Medial Ankle Sprain

Pathoanatomy

  • Ankle Joint
    • Synovial hinge joint
    • Formed by articulation formed by the distal Fibula, Distal Tibia and Talus
  • Lateral Ligaments
    • Lateral Collateral Ligament: ATFL, CFL, PTFL
    • Anterior Talofibular Ligament (ATFL)
    • Calcaneofibular Ligament (CFL)
    • Posterior Talofibular Ligament (PTFL)

Risk Factors

  • General
    • Female > Male
    • Young athletes (under 12) > adolescents (12-18) > adults
    • Height?
    • Weight
  • Orthopedic
    • History of Lateral Ankle Sprain
    • Chronic Ankle Instability
  • Occupation
    • Military Personel
    • Dancers
  • Sports
    • Netball
    • Volleyball
    • Hockey
    • Football
    • Basketball
    • Soccer[15]
  • Type of footwear
  • Type of supportive device

Differential Diagnosis

  • Fractures & Dislocations
    • Distal Tibia Fracture
    • Distal Fibular Fracture
    • Talus Fracture
    • Calcaneus Fracture
    • Subtalar Dislocation
    • Ankle Fracture (& Dislocation)
    • Peroneal Subluxation
  • Muscle and Tendon Injuries
    • Peroneal Tendon Injuries
    • Achilles Tendonitis
    • Achilles Tendon Rupture
    • Posterior Tibial Tendon Dysfunction
    • Flexor Hallucis Longus Tendinopathy
  • Ligament Injuries
    • Lateral Ankle Sprain
    • Medial Ankle Sprain
    • Syndesmotic Sprain
    • Chronic Ankle Instability
    • Intersection Syndrome Foot
  • Bursopathies
    • Retrocalcaneal Bursitis
  • Nerve Injuries
    • Peroneal Nerve Injury
    • Tarsal Tunnel Syndrome
  • Arthropathies
    • Osteoarthritis of the Ankle
    • Osteochondral Defect Talus
  • Pediatrics
    • Fifth Metatarsal Apophysitis (Iselin’s Disease)
    • Calcaneal Apophysitis (Sever’s Disease)
  • Other
    • Haglund’s Deformity
    • Posterior Ankle Impingement Syndrome
    • Sinus Tarsi Syndrome

Clinical Features

Clinical demonstration of anterior drawer test of the ankle[16]
  • History
    • Athletes typically report a sudden twisting of the ankle joint
    • They may have an inability to bear weight
    • They usually can identify the palpatory painful spot
    • Also endorse swelling, bruising (may be subacute)
    • Inability to return to sport
    • Sometimes endorse a snap or crack
  • Physical Exam: Physical Exam Ankle
    • Palpate all bony and soft tissue structures (see: Ottawa Ankle Rules)
    • If no pain along with ATFL distribution, likely not a standard LAS
  • Special Tests
    • Squeeze Test: Apply compression to medial/lateral calf
    • Anterior Drawer Test Ankle: translate distal tibia posteriorly to evaluate for laxity
    • Talar Tilt Test: Passively evert while palpating lateral talus

Diagnosis

Diagnostic ultrasound of the anterior talofibular ligament demonstrating acute rupture with the hypoechoic fluid collection. Case courtesy of Dr Maulik S Patel.

Radiographs

  • Standard Radiographs Ankle
    • Typically normal
  • Ottawa Ankle Rules
    • Decision-making rules can help determine if the x-ray is necessary
    • They are close to 100% sensitive (need citation)

Ultrasound

  • Van Dijk et al
    • Early on they found sensitivity of 92%, specificity 64%
    • Inconclusive physical exam they found sensitivity of 100%, specificity 72%
  • Among ED physicians, accuracy was similar to MRI[19]

MRI

  • Useful when other soft tissue injuries are suspected
    • Tendinous and syndesmotic trauma
    • Osteochondral lesions
    • Occult fractures
  • Joshy et al: sensitivity 92-100%, specificity 100%[20]
  • In comparison with arthroscopy, MRI (93%) was superior to US (63%) incorrectly locating the injured portion of the ATFL

Classification

  • Grade I (mild)
    • Injury: ligament fiber stretch without macroscopic rupture
    • Clinically minor swelling, palpatory tenderness
    • Hardly any functional loss
    • No increased instability
  • Grade II (moderate)
    • Injury: partial ligament tear
    • Moderate pain, swelling, and palpatory tenderness
    • Mild to moderate instability
    • Moderate functional disability
  • Grade III (severe)
    • Injury: complete tear of the ligament and joint capsule rupture
    • Severe bruising, swelling, and pain
    • Significant loss of function and an increased instability
    • Unable to bear weight and walk normally

Treatment

Prognosis

  • Nonoperative vs Operative
    • Surgical intervention is associated with increased cost, risk of complications (wound infection, nerve injury, dystrophy, poor wound healing)[22]
    • Nonoperative vs operative management of grade III has failed to demonstrate a superior modality, thus nonoperative management is often the preferred approach[23]
  • Prevention of recurrence
    • PT helps with the prevention of recurrence[22]
  • Missed time
    • Mean layoff per ankle sprain in soccer is reported between 7 and 18 days[24]
    • 83–89% of the ankle sprains require athletes less than 4 weeks of loss of activities[25]
    • RTP after surgical management ranged from 77 to 105 days in one study by Pearce[26]
  • Return to play
    • The vast majority of athletes will return to full pre-injury level of play
    • Important to distinguish the complex injuries from the simple single ligament injuries

Nonoperative

  • Indications
    • The vast majority of cases
  • PRICE Therapy
    • Typically for the first 3-5 days[27]
  • NSAIDS
    • Oral or topical appear to help[28]
  • External Support
    • Doherty et al: MA, SR found external support (taping, bracing, and orthoses) is effective for improving function[22]
    • Duration of total immobilization should be brief and early mobilization should be encouraged
    • By 1-2 weeks transition to External Ankle Brace
    • No difference between the tape, semi-rigid brace, or lace up a brace at 6 months
  • Physical Therapy
    • Doherty et al: MA, SR found PT improves self-reported function
    • Early PT combined with progressive weight-bearing
  • Manual Therapy
    • Unclear whether manual therapy helps with the function
  • Ice Therapy
    • Appears to help as a component of RICE management when combined with physical therapy
  • Acupuncture
    • It May have some benefit in SR/MA but the overall evidence is lacking due to low methodological quality
  • Unknown benefit[22]
    • Therapeutic Ultrasound
    • Low-Level Laser Therapy
    • Hyperbaric Oxygen
    • Electrical Stimulation

Operative

  • Indications
    • Unknown
  • Technique
    • Primary reconstruction

Rehab and Return to Play

Rehabilitation

  • General
    • Progressive weight-bearing
    • Early active range of motion (ROM) exercises
    • Followed by strengthening exercises, proprioceptive training, and functional exercises
  • The final phase of rehab
    • Progressively simulate the physical demands of the respective sports modality
    • Often includes jumping, turning, and twisting
  • Several rehab programs have been suggested
    • National Athletic Trainers Association[32]
    • Renstrom et al protocol[33]
    • Zoch et al protocol[34]
  • Postoperative[26]
    • 1-2 weeks: lower leg cast
    • 2-4 weeks: walking boot, active rehab

Return to Play

  • General
    • Difficult to predict when an athlete can RTP
    • No formal consensus guidelines or criteria
    • Consider the use of the Foot And Ankle Outcome Score (FAOS), which is not currently validated[35]
    • Time for RTP depends on several factors including the severity of the injury, the ability of the athlete, available resources
  • Performance-based
    • Athletes should be able to progress from simple tasks to complex tasks
    • Perform 90% of function compared to unaffected ankle
    • Progress through sport-specific tasks
  • Modalities
    • Proprioception
    • Balance (wobble board)