Orthopedics

Acute Ankle Injuries

Introduction

Although most injuries are minor and include sprains and contusions, it is important to recognize serious injuries that require immediate orthopedic referral. Children's bones are different than adults and may fracture more easily with less trauma. The bone is also more plastic and may buckle resulting in greenstick fractures. Because of the presence of growth plates, fractures may result in possible deformities. In addition, children's bones heal quicker after sustaining an injury.

Initial Assessment of Ankle Injury

  1. Immediate management if necessary: stop bleeding, manage pain.
  2. Elicit the mechanism of injury. If possible, have the patient show you how the ankle was injured using the uninjured limb.
  3. What was the person able to do immediately after the injury? More severe injuries are associated with immediate inability to bear weight or continue normal activities.
  4. How soon did the swelling begin? Acute swelling more likely associated with fracture, dislocation, or ligament tear.
  5. History of prior injuries to the ankle. Prior, incompletely healed injuries are the greatest risk factor for additional injury.

Mechanisms of Injury

Inversion

  1. Fracture of the physis (growth plate) is common with inversion injuries in patients who have open growth plates and pain with palpation of the lateral ankle (closure of the growth plate usually occurs around age 13 in girls and 15 in boys).
  2. Commonly produces injury to the lateral foot/ankle, possibly resulting in damage to the distal fibula, anterior and posterior talofibular ligaments (the anterior talofibular is the most commonly injured), calcaneofibular ligament, or proximal fifth metatarsal
  3. Rolling of the ankle when stepping into a hole or on uneven ground (inside of foot rolls inward, towards the midline)
  4. Accounts for approximately 80% of ankle injuries

Eversion

  1. Associated with more severe injury and fractures to both medial and lateral structures of the foot and ankle
  2. Inside of foot rolls outward and away from the midline

Physical Exam

  1. Observe for swelling and ecchymoses which may indicate the area of injury.
  2. Observe the patient bearing weight and walking if possible. Greater impairment may point towards more serious fracture.
  3. Palpate the entire length of the tibia and fibula for areas of point tenderness or instability that may indicate fracture of a specific bone or strain of a particular ligament.
  4. Elicit passive range of motion.
  5. Anterior drawer test of the ankle evaluates the integrity of the anterior talofibular ligament. (See AAFP article below)
  6. Inversion stress test evaluates the integrity of the calcaneofibular ligament. (See AAFP article below)

Ottawa Rules for Imaging in Ankle Injuries

Order imaging if:

  1. Patient presents with bone tenderness in posterior half of the lower 2.5 inches (6 cm) of the distal tibia or fibula (lateral or medial malleolus), or
  2. Inability to bear weight immediate after the injury.
  3. Bone tenderness over the navicular bone or base of the fifth metatarsal is an indication for foot radiographs.

Views to order

  1. AP, Lateral, and Mortise (AP with leg internally rotated 15-20 degrees) views of the ankle
  2. Foot radiographs (if indicated)

Reasons for orthopedic referral after ankle injury:

  1. Decreased/absent pulses or blanching of tissue are signs of vascular insufficiency, typically due to direct damage to blood vessels or as a result of swelling.
  2. Deficits in motor function or sensation may indicate nerve damage from direct injury to a nerve or from swelling.
  3. Any open fracture should be immediately referred.
  4. Deep lacerations over a joint must be evaluated by an orthopedic surgeon.
  5. Unreducible dislocations
  6. Complete tear of a ligament or muscle-tendon unit.
  7. Compartment syndromes

Management of Ankle Sprain

  1. Fracture has been ruled out either clinically or with negative radiographs

  2. Evaluate severity based on grading scale

    1. Grade I - Partial Tear of a Ligament

      1. Mild tenderness and swelling

      2. Little to no functional loss (can bear weight and ambulate with minimal pain)

      3. No instability

    2. Grade II - Incomplete Tear of a Ligament with Moderate Functional Impairment

      1. Moderate pain and swelling w/ ecchymoses

      2. Point tenderness over the involved ligament(s)

      3. Some loss of motion and function (moderate pain with ambulation and weight bearing)

      4. Mild to moderate instability

    3. Grade III - Complete Tear and Loss of Integrity of a Ligament

      1. Severe swelling (>4cm around the fibula) with severe ecchymoses

      2. Loss of function and movement (unable to bear weight or ambulate)

      3. Mechanical instability

  3. For uncomplicated ankle sprains (Grade I and II)

    1. RICE

      1. REST - Early light exercise and stretching is encouraged if not painful. Crutches may be used, particularly in the first few days after injury when pain is the worst. Ankle braces that limit inversion/eversion while allowing some plantar and dorsiflexion are preferred. Circumferential casting is NOT recommended.

      2. ICE - Use immediately after the injury occurs. Use for 20 min every 2-3 hours for the first 48 hours after injury, or until edema and inflammation stabilize.

      3. COMPRESSION - This will increase resorption of edema. Application should be from distal to proximal making sure that venous return is not compromised.

      4. ELEVATION -  15-20 cm above the level of the heart. This will enhance venous return and reduce swelling.

      5. NSAIDs

    2. Physical Rehabilitation

      1. Starts from day 1 until pain resolves and normal activity is resumed

      2. Involves: range of motion exercise, muscle strengthening, proprioceptive and activity specific training

      3. Analgesia with NSAIDs may facilitate rehabilitation

      4. Maintain cardiovascular fitness through aerobic exercises such as swimming, stationary biking, walking in swimming pool as tolerated.

  4. Complicated sprains (grade III) often require surgical management and should be referred to a specialist.

References

  1. Wolf, Michael W. Management of Ankle Sprains. American Family Physician. January 1, 2001. Vol 63, Number 1.  Pp 93-104. http://www.aafp.org/afp/2001/0101/p93.html Accessed 2/25/2012
  2. Metzl, Jordan D. Managing Sports Injuries in the Pediatric Office. Pediatrics in Review March 2008; 29:75-85 http://pedsinreview.aappublications.org.proxy.uchicago.edu/content/29/3/75.full?sid=379f795e-1bc6-40f1-8ada-dbb5c2445ab7 Accessed 2/25/2012
  3. Della-Giustina K and Della-Giustina DA. Emergency Department Evaluation and Treatment of Pediatric Orthopedic Injuries. Emergency Medicine Clinics of North America. 1999; 17(4):895-922.
  4. Hergenroeder, Albert. Sports Medicine: The Diagnosis and Management of Acute Musculoskeletal Injuries. Nelson's Textbook of Pediatrics. Update 10.
  5. Kaeding CC and Whitehead R. Musculoskeletal Injuries in Adolescents. Primary Care; Clinics in Office Practice. 1998; 25(1):211-223.
  6. Stanitski CL. Pediatric and Adolescent Sports Injuries. Clinics in Sports Medicine. 1997; 16(4):613-633.
  7. Patel D and Janiski C. Ankle sprains in young athletes.  Contemporary Pediatrics December 2005