Outcomes of Modified Scarf Osteotomy for Male Hallux Valgus

Category: Bunion Introduction/Purpose: Compared to women, hallux valgus in men is less common, more severe, and has higher rates of undercorrection, recurrence and greater distal metatarsal articular angle (DMAA). Bunionectomies that correct metatarsus primus varus (MPV) by valgus rotation paradoxically increase 1stMTP valgus in high DMAA, contributing to recurrence and undercorrection. While proximal valgus osteotomy or arthrodesis plus distal varus-producing metatarsal osteotomy can correct both components, there is a simpler solution. A modified Scarf osteotomy technique was developed in which the osteotomy is simultaneously translated laterally to correct MPV, while rotating the distal metatarsal in varus to correct DMAA. While previous literature on male hallux valgus is comprised of many studies using a combination of surgical techniques, all patients in this series had the same procedure. Methods: A retrospective review of prospectively collected data was performed in male patients treated with modified scarf osteotomy and soft tissue realignment for symptomatic hallux valgus, who failed conservative treatment. Preop and postop range of motion (ROM), radiographs, and validated patient reported outcome (PROM) scores including Pain VAS and SF-36, were tabulated, as well as complications, and AOFAS Hallux scores for historical comparison. There were 22 patients (26 feet), mean age 53 (17-79). Mean clinical and radiographic follow up was 24 months, and mean postop PROM’s follow up was 4.7 years. Six of 26 feet (23%) required a modified Akin osteotomy for a congruent 1stMTP joint. A subset of patients with minimum 4-year and mean 7.6 -year follow up (9 patients, 10 feet), was also analyzed. Weightbearing radiographs were evaluated for DMAA, hallux valgus angle (HVA) and 1st-2ndintermetatarsal angles (IMA). Results: Statistically significant improvements were found in VAS scores (5.8 to 1, p<0.001); SF-36 physical (44 to 56.7, p<0.001); IMA (15.9 to 8.7, p<0.001), HVA (36.1 to 15.1, p<0.001), DMAA (12.7 to 6.9, p=0.01) and AOFAS scores (44 to 79, p<0.001). Total 1stMTP ROM decreased from 60.9 to 50.8 degrees (p=0.06). One patient had delayed wound healing requiring oral antibiotics and wound vacuum application. Statistically significant improvements were maintained over time in the 7.6-year follow up sub-group, with VAS scores 6.2 to 1.3 (p<0.001), SF-36 physical from 40.8 to 61.3 (p=0.008), and SF-36 mental from 55.7 to 62.3 (p=0.002). Conclusion: This study found statistically significant improvements in both subjective validated PROM’s and objective radiographic measures using a special modification of the scarf osteotomy to address the characteristic increased DMAA that underlies complications and under correction previously reported in male hallux valgus. The corrections were well maintained at long-term follow-up including a robust correction of the DMAA.