Postoperative incomplete reduction of the sesamoids as a risk factor for recurrence of hallux valgus

It is unknown whether postoperative incomplete reduction of the sesamoids is a risk factor for the recurrence of hallux valgus. The purpose of the present study was to clarify the relationship between the postoperative relative sesamoid position and the recurrence of hallux valgus.

Dorsoplantar weight-bearing radiographs of sixty normal feet (the control group) and sixty-five feet with hallux valgus (the hallux valgus group) in a study of adult women were reviewed. The feet in the hallux valgus group were treated with a proximal metatarsal osteotomy, and the radiographs were assessed preoperatively, at the early follow-up interval (at a mean of 3.1 months), and at the most recent follow-up interval (at a mean of forty-five months). The position of the medial sesamoid was classified with a grading system ranging from I through VII as described by Hardy and Clapham. In the feet with hallux valgus, we defined a grade of IV or less as the normal position of the medial sesamoid (the normal-position group) and grade V or greater as lateral displacement of the sesamoid (the displacement group).

Fifty feet (83%) in the control group were classified as grade IV or less and ten, as grade V. All feet in the hallux valgus group were classified as grade V or greater preoperatively, forty-eight feet (74%) were classified as grade IV or less at the early follow-up evaluation, and forty-two feet (65%) were classified as grade IV or less at the most recent follow-up evaluation. The average hallux valgus angle in the hallux valgus group was 38.3 degrees (range, 25 degrees to 60 degrees ) preoperatively, 11.9 degrees (range, 4 degrees to 28 degrees ) at the time of the early follow-up, and 13.9 degrees (range, 0 degrees to 33 degrees ) at the time of the most recent follow-up. There was no significant difference in the average hallux valgus angle between the early and most recent follow-up evaluations in the feet that were considered to be in the normal-position group at the time of the early follow-up (p = 0.084). In the feet that were considered to be in the displacement group at the time of the early follow-up, the average hallux valgus angle at the time of the most recent follow-up was significantly greater than that at the time of the early follow-up (19.5 degrees +/- 8.4 degrees compared with 15.0 degrees +/- 5.8 degrees ) (p = 0.0082). The feet that were in the displacement group at the time of the early follow-up had a greater risk of having recurrence of the hallux valgus at that time than did those in the normal-position group (odds ratio, 10.0; 95% confidence interval, 2.75 to 36.33).

Postoperative incomplete reduction of the sesamoids can be a risk factor for the recurrence of hallux valgus. The identification of incomplete reduction of the sesamoids intraoperatively may allow modification of surgical procedures and improvement of the surgical results.