Peroneus brevis tendon tears: pathophysiology, surgical reconstruction, and clinical results.

Chronic peroneus brevis tendon tears are frequently overlooked or misdiagnosed. They are a more common problem than previously noted. Twenty patients were reviewed in the largest clinical series of its kind. The most reliable diagnostic sign was persistent swelling along the peroneal tendon sheath. The pathophysiologic mechanism is subclinical, or overt, subluxation of the tendon over the posterolateral edge of the fibula. This produces multiple longitudinal splits. Treatment is primarily surgical and must address both the split tendon and the subluxation that caused it. A new classification that guides surgical treatment is proposed. Debridement and repair are recommended for grade 1 tendons, which have damage to less than 50% of the cross-sectional area. Excision of the damaged segment and tenodesis to the peroneus longus are recommended for grade 2 tendons, which have destruction of greater than 50% of the cross-sectional area. Both methods must be augmented by stabilization of the etiologic subluxation. The average postoperative AOFAS score was 85. Return to maximum function is prolonged, but good-to-excellent results were found in the majority of patients.