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.

LEVEL OF EVIDENCE

Level IV, retrospective case series.