Mobility changes of the first ray after hallux valgus surgery: clinical results after proximal metatarsal chevron osteotomy and distal soft tissue procedure

The purpose of this study was to evaluate the change of the first ray mobility after PMCO and DSTP in hallux valgus patients. From May 2004 to December 2005, 82 PMCO with DSTP surgeries were performed for the management of hallux valgus deformity. The dorsiflexion mobility of the first ray of the foot was measured both preoperatively and 1 year after surgery using a modified Klaue device. The data were statistically analyzed with a paired t-test. An American Orthopedic Foot and Ankle Society (AOFAS) forefoot hallux score and patient satisfaction were also evaluated. Subjects consisted of 9 male and 73 female patients with an average age of 47.7 years (range, 19 to 74 years). The mean preoperative dorsiflexion mobility was 6.8 (range, 2.32 to 15.02) mm and the mean dorsiflexion mobility at one year after operation was 3.2 (range, from 1.7 to 5.4) mm. This decrease was statistically significant (p < 0.01). The mean preoperative AOFAS forefoot hallux score was 66.2 (range, 44 to 90) and improved to 89.1 (range, 72 to 100) by the 1-year followup (p < 0.01). Clinically, the dorsiflexion mobility of the first ray was significantly reduced after correction of hallux valgus with PMCO with DSTP. Because the stability of the first ray can be improved with PMCO with DSTP, the surgical indication for this procedure could include some patients showing hypermobility of the first ray.