The modified Lapidus procedure for hallux valgus: a clinical and radiographic analysis.

BACKGROUND: Historically, the modified Lapidus procedure has been considered technically challenging, with high rates of complications, including nonunion and malunion. The purpose of this study was to review the clinical and radiographic results of this technique for the treatment of hallux valgus associated with first ray hypermobility, specifically examining patient satisfaction and the incidence of complications.

METHODS: We retrospectively reviewed the results of the modified Lapidus procedure in 32 patients (38 feet). Evaluation included preoperative and postoperative questionnaires, physical examination, and radiographs.

RESULTS: Complete clinical data was available for 29 patients (35 feet) and complete radiographic data for 29 patients (34 feet). Average age at surgery was 54 (range 27 to 84) years. Average followup was 42 months (range 29 to 93) months. Average preoperative visual analog pain score was 7.2 and postoperative 2.3 (p < 0.001). Average preoperative AOFAS Hallux MTP-IP Score was 44.8 and postoperative 87.3 (p < 0.001). Average preoperative intermetatarsal (IM) angle was 16 degrees, and the hallux valgus (HV) angle was 34 degrees. Postoperatively, the average IM angle was 6 degrees, the HV angle 11 degrees. There were no cases of nonunion or malunion. Complications included symptomatic hallux varus in two, recurrence of hallux valgus deformity in one, deep venous thrombosis in one, and failure of fixation in one patient. Twenty-four percent of patients (7 of 29) noted the subjective sensation of midfoot stiffness and 34% (10 of 29) noted forefoot stiffness. None of these patients thought that the stiffness was a disability. Ninety percent of patients (26 of 29) were satisfied with their foot function, and 86% (25 of 29) were satisfied with the cosmetic appearance of their foot.

CONCLUSIONS: The modified Lapidus procedure results in a satisfactory clinical outcome in most patients. With meticulous operative technique, rigid internal fixation, and strict postoperative weightbearing restrictions, successful union can be achieved and complications can be minimized. Care should be taken to avoid hallux varus, and patients need to be counseled regarding a potentially long convalescent period and possible postoperative stiffness.