Shortening Scarf Osteotomy of the Fifth Metatarsal: Mid-Term Results

PURPOSE OF THE STUDY To present the results of shortening scarf osteotomy of the fifth metatarsal as an option for the treatment of forefoot deformities with calluses and associated pain around the fifth metatarsal head. MATERIAL In nine patients, 12 osteotomies were performed between 2004 and 2007. The results were evaluated at the end of 2009. One patient had one-stage bilateral surgery two had two-stage bilateral surgery. METHODS Surgical treatment was indicated in patients in whom conservative treatment had failed, and after the evaluation of load radiographs of the forefoot. The operation (sec. Barouk) is standardly performed from a longitudinal incision and involves the excision of two bone blocks, 3 to 4 mm in width, from both fifth metatarsal fragments after the osteotonny. Fixation is achieved with two Poldi screws from mini-instrumentation. The procedure can be combined with surgery on the other metatarsals. The lower extremity is then immobilised in a cast for 3 weeks. Partial weight-bearing on the heel is allowed from the second post-operative day and full weight-bearing is permitted after X-ray examination at 6 weeks. The average hospital stay is four days. RESULTS Nine patients (12 feet) underwent surgery. The average follow-up was 3.8 years (2 to 5). The average inter-metatarsal angle was 13 degrees before surgery and 4 degrees after it. The average valgus angle of the fifth metatarso-phalangeal joint was 25 degrees pre-operatively and 5 degrees post-operatively. The average metatarsal shortening was 6.5 mm. DISCUSSION Shortening shaft osteotomy allows for maximal medial translation of the fifth metatarsal and maximal correction of the angle between the fourth and fifth metatarsals. At one stage it permits metatarsal head medialisation, as does chevron osteotomy, as well as proximal translation of the head achieved by Weil osteotomy. The results of shortening scarf osteotomy have been better than those of an isolated Weil procedure, chevron osteotomy or bunionectomy. Percutaneous Krammer's method, BRT, shaft and proximal osteotomies are still discussed. CONCLUSIONS Shortening scarf osteotomy of the fifth metatarsal is indicated when conservative treatment is unsuccessful in management of calluses and fifth metatarsal head deformities, particularly in flat-footedness. It can also be used in salvage procedures following failed surgery or in digitus quintus supraductus in adults. It requires experience with first metatarsal osteotomy and a precise operative technique.