Average 4-Year Outcomes of Distal Oblique First Metatarsal Osteotomy for Stage 1 to 3 Hallux Rigidus

Background: Hallux rigidus is the second most frequent pathology of the first ray. Surgical options for degenerative metatarsophalangeal joint disease are either joint destructive or conservative procedures. The hypothesis was that oblique distal shortening osteotomy of the first metatarsal is an effective conservative technique for the management of stage 1 to 3 hallux rigidus.

Methods: We conducted a retrospective cohort study of 87 feet with Coughlin and Shurnas's stage 1-3 hallux rigidus, operated between 2009 and 2019. The cohort consisted in 72 patients (87 feet) with an average age of 57±9 (30/79) years; 22 of 87 (25.3%) feet had the first metatarsal surgery performed in isolation; 65 of 87 (74.7%) had concomitant forefoot procedures, including 31 of 87 (35.6%) with Akin phalangeal osteotomies and 34 of 87 (39.1%) with Moberg phalangeal osteotomies.We evaluated the American Orthopaedic Foot & Ankle Society (AOFAS) Scale, subjective satisfaction, joint amplitudes, shortening rate, and occurrence of postoperative complications with a mean follow-up of 51 months (16/134).

Results: The AOFAS score increased from 54.2±11.3 (25/70) preoperatively to 92.2±7.8 (62/100) postoperatively (P < .001). Patients reported excellent or good outcome in 95.4% of cases. The 40-point self-reported pain subscale score improved from 19.6 (± 10.0) to 37.4 (± 5.4), P < .001.The overall range of motion increased from 61±21 (20/110) degrees to 69±17 (35/120) degrees (P < .001). The mean first metatarsal shortening rate (SR^po) was 9.6%. Neither the Coughlin grade, the metatarsal index, or the SR^po influenced the AOFAS score. At 6-month follow-up, 15 patients had transfer metatarsalgia compared with 5 at last follow-up without requiring another surgical procedure. The risk was not significantly different according to Coughlin's stage, preoperative metatarsal index, or SR^po.

Conclusion: Oblique distal osteotomy of the first metatarsal for stage 1-3 hallux rigidus, often in combination with other first ray procedures, performed well during our follow-up time period, with a high subjective satisfaction rate and few complications.

Level of evidence: Level III, retrospective cohort study.