Background: The modified Ludloff proximal first metatarsal osteotomy is indicated for the surgical correction of moderate-to-severe hallux valgus deformity associated with metatarsus primus varus. We report the intermediate-term results of this procedure.

Methods: Ninety-nine patients (111 feet) with a mean age of fifty-six years underwent a modified Ludloff proximal first metatarsal osteotomy and a distal soft-tissue procedure at two institutions for the treatment of a moderate-to-severe hallux valgus deformity. The American Orthopaedic Foot and Ankle Society score and weight-bearing radiographs of the foot were assessed preoperatively and after a mean duration of follow-up of thirty-four months. Clinical and radiographic outcome was also compared between younger and older patients, with the arbitrarily chosen age of sixty years dividing the two groups.

Results: The mean American Orthopaedic Foot and Ankle Society score improved significantly (p < 0.0001) from 53 points preoperatively to 88 points at the time of the most recent follow-up. The mean American Orthopaedic Foot and Ankle Society score for patients who were sixty years of age or less was significantly higher than that for patients who were more than sixty years of age (91 compared with 83 points; p = 0.0057). The mean hallux valgus angle decreased significantly from 35° preoperatively to 9° at the time of the most recent follow-up (p < 0.0001), and the mean intermetatarsal angle decreased significantly from 17° to 8° (p < 0.0001). All osteotomy sites united without dorsiflexion malunion but with a mean first metatarsal shortening of 2.2 mm.

Conclusions: To our knowledge, the present report describes the largest cohort of patients undergoing a modified Ludloff osteotomy for the correction of hallux valgus deformity that has been reported in the literature. Our intermediate-term results demonstrate that the procedure achieves significant correction of moderate-to-severe hallux valgus deformity, significant reduction in forefoot pain, and significant improvement in functional outcome. Patients with an age of sixty years or less appear to have a more favorable outcome.

Level of Evidence: Therapeutic Level IV. See Instructions to Authors for a complete description of levels of evidence.