Revision Surgery for a Foot With Loss of Correction After Modified Lapidus Procedure: A Case Report

We report a case of revision surgery for a foot with loss of correction after a modified Lapidus procedure. The patient was a 68-year-old woman, with advanced hallux valgus in both feet. First, a modified Lapidus procedure and Weil osteotomy were performed on the second ray in the left foot, with a good postoperative course. Two months later, she underwent a modified Lapidus procedure on the right foot to correct severe deformity, with a preoperative hallux valgus angle of 55° to 9° and a first-second intermetatarsal (M1M2) angle of 26° to 8°. However, correction was lost early after the surgery. Plain radiographs of the right foot, obtained two months after surgery, showed a hallux valgus angle of 24° and an M1M2 angle of 14° with no bone union. Considering that the first metatarsal was dorsiflexed and adducted around the first tarsometatarsal joint, revision surgery with additional screws and an iliac bone graft was performed, which resulted in good correction with no recurrence. Dorsiflexion of the first metatarsal was thought to be the main reason for the recurrence of hallux valgus in this case. The likely reason was that when the hallux valgus recurred, dorsiflexion of the first metatarsal was greater than the opening M1M2 angle, with less rotation of the first metatarsal head. We believe that alignment correction in the sagittal plane is one of the most important aspects of the correction of hallux valgus.