Modified Lapidus procedure for hallux valgus.

A modified Lapidus procedure was introduced at Harborview Medical Center in 1979 for the treatment of symptomatic hallux valgus with hypermobile first ray. The results of the procedures were reviewed retrospectively in 32 patients with 40 feet that were operated on between 1979 and 1984. Preoperative diagnosis was symptomatic hallux valgus complex with hypermobile first ray in 33 and failed bunion surgery in 7. Follow-up ranged from 30 months to 6 1/2 years. Union of the arthrodesis site occurred in 36 (90%). The average preoperative intrametatarsal angle was 14 degrees (range 7.5 to 20 degrees) and the hallux valgus angle was 26 degrees (range 0 to 50 degrees). At healing, the angles were as follows: intermetatarsal angle 6 degrees (range 0 to 18 degrees) and hallux valgus angle 11 degrees (range -3 to 30 degrees). The average change in the length of the first metatarsal was -5 mm for those without bone graft and +4 mm for those with bone graft. Of 33 feet operated on as a primary procedure, successful results were reported in 75% by our rating system. Of 7 feet operated on for failed previous surgery, all were improved. Best results were obtained in those with multiple screw fixation, use of bone graft, and attention to plantarflexion of the first metatarsal.