Short-term outcomes of modified Lapidus procedure using the InCore® Lapidus System for hallux valgus: Case series of four cases

ABSTRACT Introduction: Hallux valgus is a common foot deformity often associated with first tarsometatarsal (TMT) joint instability. The Lapidus procedure, involving first TMT joint arthrodesis, is a well-established surgical procedure for severe cases, but the issue lies in the method of fixation. The InCore® Lapidus System is a novel intramedullary fixation system for modified Lapidus procedure. We here report the clinical experience of this system. Case presentation: We retrospectively reviewed four cases who underwent a modified Lapidus procedure using the InCore® Lapidus System and followed up at least 6 months. Surgical outcomes were evaluated by the hallux valgus (HV) and intermetatarsal (M1M2) angles on radiographs, bone union status on computed tomography (CT), postoperative pain levels, and the occurrence of complications. The HV angle improved in all four cases, ranging from 51° to 59° preoperatively and decreasing to 4° to 25° at the final follow-up. Similarly, the M1M2 angle improved in all four cases, with values decreasing from a preoperative range of 23° to 26° to a final range of 4° to 13°. All patients achieved bone union within three months, and postoperative pain was minimal (Numerical Rating Scale: 0–1) at six weeks postoperatively. No complications were observed. Clinical discussion: Theoretical advantages of the InCore® Lapidus System include the ability to achieve joint compression using the device and the intramedullary fixation design, which may provide robust stability and a high rate of bone union. The system's design potentially reduces the risk of skin irritation, a common issue with plate fixation. Our clinical experiences supported these theoretical advantages. Conclusion: The modified Lapidus procedure using the InCore® Lapidus System provided favorable short-term outcomes for hallux valgus without complications. Highlights