Hallux valgus angle as a predictor of recurrence following proximal metatarsal osteotomy.

BACKGROUND

Postoperative recurrence of hallux valgus is a common complication. We hypothesized that patients who are at higher risk for recurrence of hallux valgus following a proximal metatarsal osteotomy could be recognized preoperatively and at the early follow-up on the basis of their radiographic evaluation. The purpose of this study was to clarify the relationship between the hallux valgus angle, intermetatarsal angle, and recurrence of hallux valgus.

METHODS

We performed a case-control study of patients treated with a proximal metatarsal osteotomy for hallux valgus. Dorsoplantar weight-bearing radiographs of 72 feet were assessed preoperatively, at the early follow-up interval (mean 10 weeks), and at the most recent follow-up interval (mean 33 months).

RESULTS

The rate of recurrence was 13.9% (ten feet). Risk factors for recurrence were preoperative hallux valgus angle >40° [odds ratio (OR) = 5.1; 95% confidence interval (CI) 1.3-20.8]. Decreased risks of hallux valgus recurrence were a hallux valgus angle ≤ 15° (OR = 0.036, 95% CI = 0.0056-0.24, p = 0.0005), and an intermetatarsal angle <10° (OR = 0.083, 95% CI = 0.015-0.46, p = 0.0075) at the time of the early follow-up with the numbers available.

CONCLUSIONS

Our radiographic results indicated that a preoperative hallux valgus angle >40° can be a risk factor for hallux valgus recurrence. Decreased risk factors for recurrence included hallux valgus angle ≤ 15° and an intermetatarsal angle <10° at the early follow-up. These risk factors may be helpful for modifying surgical procedures, improving surgical outcome, and predicting hallux valgus recurrence.