Ligament and Tendon Injuries
Tendon injuries typically result from either hyperdorsiflexion, when the peroneal tendon is injured, or sudden plantarflexion, which results in an Achilles tendon injury. Patients with an Achilles tendon rupture have severe pain and are unable to walk on their toes, run, or climb stairs. Ligamentous sprains tend to result from inversion and eversion injuries. The most common ankle sprain involves the anterior talofibular ligament. An isolated sprain of the medial deltoid ligament is rare, and an associated fibular fracture (Maisonneuve fracture) or syndesmotic ligament injury may be present. Any injury with signs of neurovascular compromise requires immediate attention.
Diagnosis and Differential
Evaluate the ankle along with the joints above and below the injury. A positive Thompson test (with the patient lying prone and knee flexed at 90°, the foot fails to plantarflex when the calf is squeezed) is diagnostic of Achilles tendon rupture. Palpate the proximal fibula for tenderness resulting from a fracture or fibulotibialis ligament tear. Squeeze the fibula toward the tibia to evaluate for syndesmotic ligament injury. If tenderness is isolated to the posterior aspect of the lateral malleolus, then a peroneal tendon subluxation may be present.
The Ottawa Ankle Rules guide clinicians in determining when imaging studies are needed for suspected ankle injuries (Fig. 175-1).
Ottawa ankle rules for ankle and midfoot injuries. Ankle radiographs are required only if there is any pain in the malleolar zone or midfoot zone along with bony tenderness in any of these four locations or the inability to bear weight both immediately and in the ED.
Joint stability is the primary determinant of a treatment plan for a sprain. Instability is suspected based on physical examination and radiography. The examiner may perform the anterior drawer and talar tilt tests to assess stability. If the examiner is unable to perform reliable stress testing, the injury is considered potentially unstable. Any asymmetry in the gap between the talar dome and the malleoli on the talus x-ray view suggests joint instability.
Emergency Department Care and Disposition
If the patient has a stable joint and is able to bear weight, then protection (with an elastic bandage or ankle brace), rest, ice, compression, and elevation (PRICE) for up to 72 hours is indicated. Prescribe analgesics, and add motion and strength exercises within 48 to 72 hours. The patient should follow-up in 1 week if the pain persists.
A patient with a stable joint who is unable to bear weight requires an ankle brace and orthopedic follow-up.
A patient with an unstable joint requires a posterior splint and referral to an orthopedist for definitive care.
Treatment of Achilles tendon rupture includes splinting in plantar flexion, nonweightbearing, and referral to ...