The Lapidus procedure: a prospective cohort outcome study.

BACKGROUND: Multiple reports are found in the literature about the surgical treatment of hallux valgus deformities. Few, however, are prospective outcome studies. The purpose of this study was to prospectively look at the functional outcome of patients with moderate and severe hallux valgus deformities (intermetatarsal angle of more than 14 degrees and a hallux valgus angle of more than 30 degrees) after the Lapidus procedure.

METHODS: Indication for surgery and inclusion into the study was failure of nonoperative management for metatarsus primus varus and painful hallux valgus deformities. Data was collected using the AOFAS Hallux Metatarsophalangeal Interphalangeal Scale, Visual Analog Pain Scale, clinical examination, weightbearing radiographs, and a patient satisfaction questionnaire. Data was collected preoperatively, 6 weeks after surgery, 6 months after surgery, and then yearly. One hundred and five feet in 91 patients were followed for an average of 3.7 years (range, 18 months to 6.2 years). Sixty-two patients were female and 29 were male. The average age at surgery was 41 years (range, 20 years to 71 years).

RESULTS: The AOFAS Hallux Metatarsophalangeal Interphalangeal Scale scores increased from 52 preoperatively to 87 points at most recent follow-up (p <.001). The average intermetatarsal angle preoperatively was 18 degrees and 8.2 degrees at most recent follow-up. Between the 1-year and 3.7-year follow-up visits, only.3-degree increase of the intermetatarsal angle was noted. The average hallux valgus angle preoperatively was 37 degrees and 16 degrees at most recent follow-up. Less than 1-degree increase in the hallux valgus angle was noted between the 1-year to 3.7-year follow-up visits. Complications included tarsometatarsal nonunion in seven patients. Five patients lost correction and all seven patients had a revision procedure done for pain. Removal of hardware was necessary in eight patients, minor wound problems occurred in two patients, superficial neuroma in two patients, and transfer metatarsalgia in four.

CONCLUSIONS: The Lapidus procedure obviously is not the answer to all bunion deformities, but with proper technique and attention to detail it is an excellent alternative treatment for moderate to severe metatarsus primus varus and hallux valgus deformities.