Results of Modified Lapidus Arthrodesis Procedure Using Medial Eminence as an Interpositional Autograft

Abstract

The Lapidus procedure has received wide acceptance as a valuable operation for correcting moderate to severe hallux valgus, especially in the presence of hypermobility. However, shortening of the first ray inherently occurs as the first metatarsocuneiform joint cartilage and subchondral bone are resected in preparation for arthrodesis. The purpose of this study was to radiographically compare the degree of shortening of the first ray with and without the use of the first metatarsal medial eminence as an interpositional autograft at the site of metatarsocuneiform fusion. Preoperative and postoperative radiographs were measured in 35 consecutive patients who underwent 37 modified Lapidus procedures for hallux valgus repair. In group A, 20 surgeries were performed without use of the interpositional autograft, and served as the control. In group B, 14 surgeries were performed using the medial eminence as an interpositional autograft. The mean amount of first ray shortening was 5.3 ± 1.66 mm in group A and 2.69 ± 1.56 mm in group B, and this difference was statistically significant ( P < .001). All patients progressed to complete union, and the median follow-up was 6 months (range, 4–60). Based on these results, the use of the medial eminence as an interpositional autograft in conjunction with Lapidus arthrodesis resulted in a 49.2% reduction in the amount of shortening of the first ray and proved to be a useful source of readily available bone graft.