Extended Chevron Osteotomy in the Management of Mild-Severe Hallux Valgus: Clinical Results in a Long-Term Follow-Up

Abstract

Category: Bunion Introduction/Purpose: Hallux Valgus (HV) is a forefoot complex deformity. More than 200 surgical techniques for its treatment have been described, Chevron Osteotomy and its modifications represent a widely accepted highly reproducible option in the HV treatment. Since described in 1991 the Extended Chevron Osteotomy (ECO) represents a distal osteotomy with a plantar diaphyseal extension. Biomechanically the advantages it offers are even greater stability, early consolidation by increasing the contact surface and correcting the facet with a minimum shortening. It also offers lower morbidity and a lower rate of complications. However, there is controversy regarding long-term follow-up for most of these procedures. This study aims to demonstrate ECO for the correction of moderate to severe HV in a long-term follow-up. Methods: We reviewed 25 feet (20 patients) with moderate to severe HV in which the Intermetatarsal Angle (IMA) greater than 16⁰. The mean age was 64 years and the patients were followed by a mean of 30 (14 to 59) months. Additionally, 8 patients (N=12 feet) were followed with a mean of 68 (50 to 86) months. The following scales were applied before and after surgery: the functional scale of the American Orthopaedic Foot & Ankle Society (AOFAS) for the forefoot and the Visual Analog Scale (VAS). In the same way, the radiographic measurements corresponding to HV were made pre and postoperative. This research study was approved by our institution and hospital research ethics committee. Additionally, all the patients were reviewed under the Mexican law NOM-004-SSA3-2012 regarding Clinical file and privacy rights. Results: In the AOFAS for forefoot and VAS scales an improvement of 51.28 (CI95% 46.34 to 56.21) -6.08 (CI 95%-6.65 to -5.50) points, respectively. Regarding the angular values, the correction was -9.08⁰ (CI 95% -10.29 to -7.86) for the IMA. There was one foot with post-surgical infection (4%) and two feet (8%) with transfer metatarsalgia. Additionally, we documented a mean AOFAS forefoot score of 90.16 (+- 5.27) and a mean of 0.8 (+- 0.4) VAS scale during a second follow-up period of 68 months (range from 50 to 86 months) in 8 patients (N=12 feet). Statistically significant differences (p <0.05) were documented by the means of these long-term follow-up periods in the AOFAS score and VAS scale regarding the pre-surgical scores. Conclusion: According to the results obtained, we consider that the ECO technique for the treatment of moderate to severe HV provides significant functional improvement and angular correction (p <0.05) and good clinical outcomes on both long-term follow-up periods. ECO technique represents a highly reproducible option when performing HV correction.