NOTE: For the purpose of this protocol, all surgical procedures involving osteotomy of the first metatarsal (significant bone resection, excision, surgical fracture, etc.) or fusion of the first metatarsal phalangeal joint were considered qualified procedures, whether or not performed specifically to repair a bunion (hallus valgus deformity). Surgical techniques accompanied by minimal bone excision (e.g. cheilectomy) or procedures limited to soft tissue repair were not eligible for this study.