Achilles tendon injury

The Achilles tendon, the largest tendon in the body, may be partially or completely ruptured and is a typical injury of active people. Rupture typically occurs when a sudden stress is applied to an already weakened or degenerated tendon. It's a common sports injury after rapid acceleration and pivoting. Patients usually describe the sensation of being struck or kicked at the back of the ankle, often with an audible “pop”. A gap in the tendon may be palpated, and Thompson test may be positive. Whether they should be treated conservatively or surgical is controversial. In either case, proper rehabilitation is important.

Etiology

Sports involving running and rapid acceleration and pivoting, like sprinting, basketball, and football, have higher risk of rupture. Recurrent microtrauma causes degeneration of the tendon, predisposing to rupture.

Clinical features

Patients usually describe the sensation of being struck or kicked at the back of the ankle, often with an audible “pop”. Pain is often present, but not always.

Diagnosis and evaluation

A “gap” or “defect” may be palpated in the tendon at the site of the rupture. Plantar flexion of the ankle is decreased but not completely absent (due to intact tibialis posterior).

Thompson test involves having the patient in prone position with their feet hanging off the table. Then, manually compress the calf. In normal cases this causes plantar flexion of the ankle. If plantar flexion does not occur, the test is positive and indicates Achilles tendon rupture.

Tendon rupture may be diagnosed based on clinical findings, but ultrasound and MRI may be used to assist in the diagnosis.

Treatment

Whether Achilles tendon ruptures should be treated conservatively or operatively is controversial. Previously it was thought that conservative treatment has a higher rate of recurrence, but that may not be true if conservative treatment is followed up by proper rehabilitation. Anyway, both are suitable options. Initial treatment in both cases follows the RICE principle.

Conservative treatment involves casting or bracing. Surgical treatment involves repairing the tendon. Both should be followed up by rehabilitation and physical therapy to achieve maximum potential function and reduce recurrence. If treated conservatively, the foot should be casted or braced in a plantarflexed position for 3 – 4 weeks, followed by a neutral position for some more weeks.