A radiographic evaluation of the scarf osteotomy for the correction of hallux valgus

Abstract A prospective radiographic study was performed on 13 patients (22ft) undergoing SCARF osteotomy with an average age of 52 years (range, 25–78). Standardised weight bearing anterior-posterior radiographs were taken preoperatively and at 6 months post-operatively. These were compared to determine changes in the intermetatarsal angle (IMA), hallux valgus angle (HVA), distal metatarsal articular angle (DMAA) and joint congruency angle (JCA). Correction of sesamoid position and metatarsal length changes were also assessed. The results showed a median reduction of IMA of 6°, HVA of 16°, DMAA of 6° and an improvement in JCA of 11°. Improvement of medial sesamoid displacement beneath the first metatarsal head was seen post-operatively. Metatarsal length was assessed by comparing the ratio of the length of the first to second metatarsal pre and post-operatively. No shortening was found. There was no incidence of avascular necrosis or delayed union. This study indicates that the SCARF osteotomy produces effective radiological correction of hallux valgus. It corrects sesamoid displacement and avoids shortening of the first metatarsal.