A radiographic evaluation of oblique closing base wedge osteotomies for the correction of hallux abductus valgus

Abstract

The radiographs of 21 patients who underwent oblique closing base wedge osteotomies (OCBWO) were evaluated to determine the degree of intermetatarsal (IM) angle reduction, first metatarsal position and length. All the procedures were performed using association for osteosynthesis rigid internal fixation, lag technique and hinge axis principles. All patients were immobilized post-operatively for 6 weeks in a below-knee cast (non-weightbearing). The results showed a mean reduction in the IM angle of 8.9° (SD ± 2.3) which was highly significant ( P < 0.001). The mean decrease in the metatarsal declination angle (dorsiflexion) was 0.4° (SD ± 3.08). This was less than the threshold for clinically significant metatarsal elevatus (5°). The first metatarsal was shortened on average by 1.76 mm (SD ± 0.98) which is within the safety net of 3–4 mm, above which is associated with complications. This study indicates that the OCBWO can be an effective, predictable and stable procedure for reducing appropriate hallux valgus deformities without clinically significant elevatus or shortening.