DISTAL CHEVRON OSTEOTOMY WITH LATERAL RELEASE FOR TREATMENT OF HALLUX-VALGUS DEFORMITY

From 1986 to 1990, 42 feet in 30 patients had a combined chevron osteotomy and lateral release to correct their painful bunion deformity. Seventeen patients, 23 feet, were available for follow-up. The purpose of this study was to evaluate the outcome of this procedure and to determine the incidence of avascular necrosis. The patients were examined by an independent examiner, radiographs obtained, and questionnaires filled out. Avascular necrosis was determined using plain films read by a musculoskeletal radiologist who did not know the outcomes. The average age was 45 years at the time of the procedure. Average follow-up was 50 months. The pre-operative intermetatarsal angle averaged 13-degrees and the hallux valgus angle averaged 31-degrees. At study follow-up, the intermetatarsal angle averaged 8-degrees and the hallux valgus angle averaged 17.5-degrees. The results were graded by the Mayo Clinic Forefoot Scoring System (75-point scale) and a subjective scoring system. Average postoperative Mayo Clinic score was 67. Fifteen feet were subjectively rated as excellent, six as good, and two as fair. Complications occurred in four feet. Hallux varus occurred in two feet, extension contracture in one foot, and an infection in one foot. None of the feet developed definite radiographic evidence of avascular necrosis. Distal chevron osteotomy combined with a lateral release for corrective bunion surgery has come under scrutiny, because of the risk of avascular necrosis of the first metatarsal head. However, our study showed no evidence of avascular necrosis on radiographs. In addition, 91% of patients had good to excellent results at an average 50-month follow-up.