Is generalized ligamentous laxity a contraindication for a modified Broström operation to treat chronic lateral ankle instability? A systematic review.

BACKGROUND

To investigate whether generalized ligamentous laxity (GLL) really is a contraindication for use of the modified Broström operation to treat chronic lateral ankle instability (CLAI).

METHODS

Case series and cohort studies of the clinical outcomes of the use of the modified Broström operation to treat patients with CLAI and GLL were systematically reviewed and a meta-analysis conducted.

RESULTS

A total of 447 patients (458 ankles) from 2 case series and 3 cohort studies were systematically analyzed, with mean follow-up times that ranged from 12 to 108 months. Postoperative foot and ankle values analyzed included foot and ankle outcome scores, foot and ankle ability measurements, Karlsson-Peterson ankle scores, American orthopedic foot and ankle society (AOFAS) ankle-hindfoot scores, Tegner activity level scores, anterior talar translations (ATT), talar tilt angles (TTA) and adverse events. Reliable postoperative ankle stability was achieved in CLAI patients with GLL in the 2 case series without major complications. Suture-tape augmentation combined with a modified Broström operation was employed in 1 case series, and the modified Broström operation was only performed in CLAI patients with GLL if the contralateral uninjured ankle showed normal TTA and ATT in another case series. In the 3 cohort studies, 2 reported poorer outcomes and a significantly greater failure rate in patients with GLL compared with those without GLL, and 1 reported equivalent clinical results. In the further pooled data analysis, there was a significant difference in the postoperative TTA value between the GLL and non-GLL groups (SMD: 0.885, 95% CI [0.599-1.171], P = 0.000; I2 = 98%, P = 0.000). The incidence of postoperative recurrent instability was significantly higher in the GLL group (RR: 6.265, 95% CI [2.563-15.309], P = 0.000; I2 = 0%, P = 0.985). Two studies reported the preoperative Beighton score in 7 ankles with postoperative recurrent instability, 6 of which had a preoperative Beighton score ≥7.

CONCLUSIONS

GLL may not be a contraindication to the modified Broström operation being used to treat CLAI. However, some augmentation operations may be combined with the classic modified Broström operation, especially for those patients with preoperative Beighton scores ≥7, or with abnormal ATT and TTA in the contralateral ankle. This assertion should be further confirmed by a prospective, large-sample cohort and control study focused on this special population who are at a higher risk of developing postoperative instability.

LEVEL OF CLINICAL EVIDENCE: Level 3.