Ligament Augmentation Reconstruction System (LARS) for Ankle Lateral Ligament Reconstruction in Higher-Risk Patients: A 5-Year Prospective Cohort Study

Orthop J Sports Med. 2022 May 9;10(5):23259671221093968. doi: 10.1177/23259671221093968. eCollection 2022 May.

Abstract

Background: The modified Broström-Gould (MBG) procedure is the gold standard for patients with chronic ankle instability (CAI), but it is relatively contraindicated for patients with higher body weight or generalized ligamentous laxity (GLL). The use of the ligament augmentation reconstruction system (LARS) is an alternative.

Hypothesis: It was hypothesized that clinical outcomes would be similar in patients with increased body weight (>90 kg) or GLL, relative to controls.

Study design: Cohort study; Level of evidence, 2.

Methods: A total of 66 patients satisfying the inclusion criteria were invited to participate and were divided into 3 groups: controls (no risk factors for inferior clinical outcome), patients with body weight >90 kg, and patients with GLL (Beighton score, ≥5 of 9). All patients underwent imbrication of the lateral collateral ligament complex augmented with the LARS. Primary outcomes of interest were Tegner activity scale (TAS) and Foot and Ankle Outcome Score (FAOS) subscale scores. Secondary outcomes were recurrence of ankle instability, the need for further surgery, and/or complications. Patients were reviewed at 2 and 5 years postoperatively, and outcomes between groups were compared using repeated-measures analysis of variance.

Results: Complete data were available for 63 patients (21 patients in each group). TAS improved in all groups from preoperatively to 2 years and 5 years postoperatively (P < .001 for all). Relative to the controls, the TAS scores were lower in the >90-kg group at 2 years and 5 years (P < .001 for both periods), while the GLL group had similar scores to controls at both postoperative periods. Both the >90-kg and the GLL groups showed no significant difference in improvement on any FAOS subscale scores relative to the controls, at both 2 and 5 years postoperatively. There were no recurrences, repeat surgeries, or major complications.

Conclusion: Relative to controls, patients with body weight >90 kg or GLL had similar FAOSs, and TAS scores were lower in the >90-kg group, at 2 and 5 years, after the use of the LARS to augment lateral collateral ligament imbrication for CAI. Use of the LARS in this manner is a viable option in patients for whom the MBG procedure is relatively contraindicated.

Keywords: BMI; GLL; LARS ligament; ankle instability.