LONG TERM RESULTS OF MITCHELL’S PROCEDURE FOR HALLUX VALGUS DEFORMITY: A 5- TO 20-YEAR FOLLOW UP IN 204 CASES

Abstract

Introduction: We present the long term results in 204 cases of Hallux Valgus deformity correction using a modified Mitchell’s osteotomy.

Methods: 168 patients (204 feet) that had Mitchell’s osteotomies between 1986 and 2001 were recalled for clinical and radiological evaluation. The patients had hallux valgus angles of up to 50o and intermetatarsal angles of up to 20o. They all had a modified procedure using two crossed Kirschner wires to fix the capital fragment into plantar displacement and angulation. Lateral soft tissue release was performed when deemed necessary during the procedure. Mild to moderate arthritis of the 1st metatarsophalangeal joint was not a contraindication. The AOFAS scores as well as any complications were recorded and the Xrays were used to measure hallux valgus and intermetatarsal angles. Mann-Whitney U test was used to analyze data.

Results: The mean follow up was 12.9 years. The mean AOFAS score improved from a preoperative of 49.6 to a postoperative of 87.9 points (p=0.004), due to improvement in the pain (14.2 Vs 37.6, p=0.001) and function (30.6 Vs 39.8, p=0.043) parameters. 57 cases (27.9%) had Hallux Valgus angles > 40o. Lateral soft tissue release was performed in only 16 of these cases with no significant difference in the postoperative Hallux Valgus angle compared to the ones not requiring soft tissue release (21.3o Vs 20.8o, p=0.08). There was a decrease in the pre-operative Vs post-operative incidence of lateral metatarsalgia and symptomatic callosities (18.33% Vs 11.8%, p=0.023). We had only one case of avascular necrosis.

Discussion/Conclusion: Mitchell’s osteotomy is a reliable technique with successful outcomes and minimal complications when performed with accurate surgical technique, stable fixation and lateral soft tissue release when appropriate. It may also be successfully performed for Hallux Valgus angles > 40o. We believe that it has still got a role in the treatment of Hallux Valgus.