Mitchell's osteotomy with mini-plate and screw fixation for hallux valgus.

Background: The aim of this study was to evaluate the use of mini-plate and screw fixation to stabilize the first metatarsal osteotomy in patients undergoing Mitchell bunionectomy, with the outcomes of interest being radiological alignment and the time to bony union.

Methods: We used mini-plates and screws in 43 feet of 25 patients to avoid cast immobilization and prevent osteotomy displacement. The mean age at operation was 45.4 ± 13.4 years (range, 17.0-65.0 years). The mean follow-up was 16.9 ± 3.6 months (range, 12.0-30.0 months). The hallux valgus angles, intermetatarsal angles, and American Orthopaedic Foot and Ankle Society (AOFAS) forefoot scores were evaluated preoperatively and at postoperative month 12.

Results: The mean preoperative value for the hallux valgus angle was 35.9 ± 4.4 degrees (range, 26.0-45.0 degrees) and for the intermetatarsal angle was 12.1 ± 1.4 degrees (range, 10.0-15.0 degrees). The mean postoperative value for the hallux valgus angle was 16.0 ± 2.12 degrees (range, 12.0-20.0 degrees) and for the intermetatarsal angle was 7.7 ± 1.2 degrees (range, 5.0-10.0 degrees). The mean AOFAS score was 50.5 ± 12.8 points (range, 30.1-76.0 points) preoperatively and 75.9 ± 11.3 points (range, 43.3-92.3 points) at postoperative month 12. Improvement of range of motion of the metatarsophalangeal joint, pain relief, and satisfactory alignment of the first ray were achieved in 41 feet (95.3%).

Conclusions: We recommend this fixation for Mitchell's bunionectomy because it provided stable fixation without the need for casting. Methods: Level IV, retrospective case series.