Percutaneous distal osteotomy of the fifth metatarsal for correction of bunionette.

BACKGROUND: Distal osteotomy of the fifth metatarsal is indicated in the surgical treatment of bunionette and varus deformities of the fifth toe in patients with a valgus deviation of the fifth metatarsal. The aim of this study was to evaluate the results of a subcapital percutaneous osteotomy of the fifth metatarsal in the treatment of this disorder.

METHODS: From 1996 to 2006, thirty consecutive percutaneous distal osteotomies of the fifth metatarsal were performed in twenty-one patients for the treatment of a painful prominence of the head of the fifth metatarsal. Combined procedures were performed, including a first metatarsal osteotomy in sixteen feet for hallux valgus treatment and a distal open osteotomy of the second metatarsal for painful dorsal dislocation of the second metatarsophalangeal joint in eight feet. The patients were assessed at a mean of ninety-six months with a radiographic and clinical protocol that made use of the American Orthopaedic Foot & Ankle Society (AOFAS) Lesser Toe Metatarsophalangeal-Interphalangeal Scale.

RESULTS: The AOFAS score improved from a mean and standard deviation of 51.9 ± 10.2 points preoperatively to 98.4 ± 2.6 points at the time of final follow-up. In 73% of feet there was complete resolution of pain at the fifth metatarsophalangeal joint without any functional limitation (AOFAS score of 100). In 20% of the cases the AOFAS score was 95 points with some decrease in function and a need to use comfortable shoes. In the remaining 7% of patients the AOFAS score was 93 points with mildly asymptomatic malalignment. No nonunions or recurrences were observed.

CONCLUSIONS: The percutaneous procedure described here is a reliable technique to perform a distal transverse osteotomy of the fifth metatarsal to correct a painful varus fifth-toe deformity with prominence of the fifth metatarsal head. The clinical results are comparable with those reported with traditional open techniques, with the advantages of a minimally invasive surgical procedure, substantially shorter operating time, and a reduced risk of complications.