Background: This study compares two diaphyseal osteotomies (scarf and Ludloff) which correct moderate to severe metatarsus primus varus. This is a single surgeon, prospective cohort study with clinical and radiological follow up at twelve months.

Materials and Methods: There were 57 patients in each group. Both groups were similar in terms of age, gender and preoperative deformity. Clinical assessment included visual analogue scale questionnaires for subjective assessment and functional activities and the American Orthopaedic Foot and Ankle Society (AOFAS) score. Standardised weight bearing radiographs were analysed.

Results: There was no stastically significant difference between the two groups at 6 and 12 months in subjective satisfaction, AOFAS score, improvement in functional activities and range of movements. The improvement in pain (at best) and transfer lesions at 12 months was significantly better in the scarf group (p< 0.05). The radiological results at 6 and 12 months including intermetatrsal angle (p< 0.001), hallux valgus angle (p< 0.01), distal metatarsal articular angle and seasmoid position (p< 0.05) were significantly better in the scarf osteotomy group. There were three cases (5%) of delayed union in the Ludloff group. Two of these healed with dorsiflexion malunion. One patient in the Ludloff osteotomy group developed a complex regional pain syndrome. There were two wound complications in the scarf group.

Conclusion: Overall the patients who had a scarf osteotomy had a superior outcome at 6 and 12 months.