Correction of moderate to severe hallux valgus with isometric first metatarsal double osteotomy.

BACKGROUND

The operative treatment for the moderate to severe bunion continues to present challenges. The indications for a single, double, or triple first ray osteotomy remain controversial. In addition, it is not clear whether an opening wedge osteotomy leads to clinically relevant arthritis at the first metatarsophalangeal joint. However, it is this theoretical concern that has led the authors to develop an isometric correction of the first ray.

METHODS

Thirty-two patients underwent operative correction of hallux valgus with a double osteotomy of the first metatarsal using an opening wedge proximally and a closing wedge distally. The mean follow-up period was 59.3 months with a range of 55 to 65 months.

RESULTS

The 1-2 intermetatarsal angle preoperatively was a mean of 18.9 degrees (range 17-23), correcting postoperatively to a mean angle of 8.6 degrees (range 5-12), for an average correction of 10.4 degrees (range 6-16). The postoperative AOFAS scores were 39.4 out of 40 points for pain, 42.4 out of 45 points for function, and 15 points for alignment. The total score was excellent with 94.2 out of 100 possible points. Radiographic union occurred in all cases. There was one case of painful edema of the foot and two cases of early avascular necrosis (AVN) diagnosed by residual pain at the hallux metatarsophalangeal joint and transient osteopenia of the metatarsal head on radiographs. No late sequelae associated with AVN such as arthritis or metatarsal head collapse were noted with long-term follow-up. These healed within months without specific treatment.

CONCLUSION

A double osteotomy of the first metatarsal with a nonlocking, low-profile plate was an effective procedure for correcting severe hallux valgus that carried a low complication rate and high patient satisfaction. It has clear advantages over isolated opening wedge procedures, including potentially better correction especially in those bunions associated with an increased distal metatarsal articular angle.

LEVEL OF EVIDENCE

Level IV, retrospective case series.