Correction and prevention of deformity in type II tibialis posterior dysfunction.

UNLABELLED: Cobb described a method of reconstruction in Johnson and Strom Type II tibialis posterior dysfunction (TPD) using a split tibialis anterior musculotendinous graft. We assessed patient function and satisfaction after a modified Cobb reconstruction in a group of patients with a narrow spectrum of dysfunction, examined a modification of the Johnson and Strom classification to emphasize severity of deformity, and assessed the ability of the technique to prevent subsequent fixed deformity. We prospectively followed 32 patients managed by this technique and a translational os calcis osteotomy with early flexible deformity after failed conservative treatment. There were 28 women and four men with unilateral disease. The average followup was 5.1 years. Staging was confirmed clinically and with imaging. The modified surgery involved a bone tunnel in the navicular rather than the medial cuneiform with plaster for 8 weeks followed by orthotics and physiotherapy. All of the osteotomies healed and 29 of the 32 patients could perform a single heel rise test at 12 months. The mean postoperative American Orthopaedic Foot and Ankle Society hindfoot score was 89. One patient had a superficial wound infection and one a temporary dysesthesia of the medial plantar nerve; both resolved. The observations suggest the technique is a comparable method of treating early Johnson and Strom Type II TPD. LEVEL OF EVIDENCE: Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.