The Role of Toe Flexor-to-Extensor Transfer in Correcting Metatarsophalangeal Joint Instability of the Second Toe

Abstract

The purpose of the study was to evaluate the outcome of flexor digitorum longus (FDL) transfer to the dorsum and to identify a possible continued role for this transfer in conjunction with additional surgeries for second metatarsophalangeal joint (MTPJ) instability. We carried out a retrospective analysis on patients with second MTPJ instability for which the FDL transfer was done as the primary procedure between 1996 and 2001. The patients were examined for functional status, residual pain, and satisfaction. A total of 64 feet (59 patients) were evaluated, with an average followup period of 45.2 (16 to 82) months. A cross-over second toe deformity was present in 56 feet (87%) with a stage II deformity being the most common (18 feet). There also were seven feet with vertical subluxation. An additional second metatarsal Weil osteotomy was done in 29 feet (45%), a proximal interphalangeal (PIP) joint resection arthroplasty in 22 feet, and a PIP joint fusion in nine feet. At final followup of the 59 feet that were physically examined, 22 (37%) had residual second MTPJ dorsiflexion contracture and 16 feet had persistent medial deviation. The second toe was stable to stress manipulation in 46 feet (78%). The mean toe pulp to ground distance on standing was 3 mm, and strong toe grasp was possible in 45 feet. There were 20 complications in 64 feet. Twenty-five patients (29 feet) were very satisfied, 15 satisfied with minor reservations, six with major reservation, and 14 patients were unhappy with the outcome. The American Orthopaedic Foot and Ankle Society functional score was on average 82 points (47 to 100) at final followup. Although the function of the second toe improved in most patients as a result of pain relief, a substantial number of the patients in this study remained dissatisfied because of residual stiffness of the toe. The flexor tendon transfer remains an important procedure in correction of second toe instability but must be used with a full understanding of potential complications and patient dissatisfaction.