Diagnosis and Surgical Management of Congenital Laxity of the Fibularis Musculotendinous Unit Resulting in Hyperextension of the Tarsus in 14 Calves.

Abstract

To describe the diagnosis and surgical management of congenital laxity of the fibularis tendon resulting in hyperextension of the tarsus in calves. Case series. Fourteen calves (3 unilateral, 11 bilateral) diagnosed with congenital tarsal instability caused by laxity of the fibularis musculotendinous unit resulting in hyperextension of the tarsus. Diagnosis was made by clinical and radiologic assessments. The tarsus was surgically prepared and an incision made on the dorsal surface of the tarsus after intrathecal anesthesia with the calf sedated. A locking-loop suture (4 loops) was applied to the fibularis tendon using polyglactin 910. The free ends of the suture were then tied to the shank of a cortical bone screw inserted in the proximal metatarsus. The calves were evaluated on postoperative days 15, 30, and 60 and were walking normally. Congenital tarsal instability because of laxity of the fibularis musculotendoninous unit is described and surgical treatment directed at shortening the tendon shows promising results.