Modified Broström Procedure for Chronic Ankle Instability with Generalized Joint Hypermobility

Abstract

Category: Sports Introduction/Purpose: Chronic ankle instability with generalized joint hypermobility (GJH) is considered a contraindication for the modified Broström procedure. The most widely accepted definition of GJH is a Beighton-Horan score of ≥4 on a 9-point scale. However, it is not clear if this criterion can be applied to determine the GJH that would lead to a poor outcome after the modified Broström procedure. Methods: The modified Broström procedure was performed in 32 patients with chronic ankle instability with GJH, if the contralateral uninjured ankle showed a normal varus talar tilt and anterior talar translation during the stress tests. We hypothesized that when the contralateral uninjured ankle shows a normal varus talar tilt and anterior talar translation during stress tests in patients with GJH, GJH may have a smaller effect on the ankle ligaments, and the modified Broström procedure in these cases may have satisfactory outcomes. The mean patient age at surgery was 21.7 years. The mean follow-up duration was 27.4 months. Results: The Karlsson-Peterson ankle score significantly improved from 63.6 ± 7.1 points (p< 0.001; 95% CI, 22.1 – 29.7) preoperatively to 90.4 ± 6.7 points at the final postoperative follow-up. Sixteen patients were very satisfied with the results, 10 patients were satisfied, 3 patients rated their satisfaction as fair, and 1 patient was dissatisfied with the results. We stratified the clinical outcomes according to the Beighton scores. There was no correlation between the Beighton scores and the Karlsson- Peterson ankle scores at the last follow-up (Spearman’s correlation coefficient, -0.11; p= 0.591). However, 1 patient with a Beighton score of 8 points and 1 patient with a score of 9 points had lower Karlsson-Peterson ankle scores (82 and 85, respectively) compared to the average scores at the last follow-up. Conclusion: The modified Broström procedure was successful in patients with chronic ankle instability with GJH, if the contralateral uninjured ankle showed a normal varustalar tilt and anterior talar translation during the stress tests. The repaired ligaments may eventually stretch out in patients with GJH secondary to connective tissue disorders such as Marfan syndrome as these patients have been found to have inherent connective tissue extensibility. However, GJH includes mild joint hypermobility without any symptoms or problems except increased joint range of motion. When the contralateral normal ankle shows negative stress tests that the modified Broström procedure may be successful.