Summary

A retrospective analysis of patients who underwent revision ACL reconstruction with or without lateral extraarticular tenodesis (LET) identified similar failure rates between groups; however, patients who had an additional LET demonstrated statistically significant improvements in activities of day living and sport and recreation KOOS subdomain scores at a minimum 2 year follow up.

Abstract

Introduction

Revision anterior cruciate ligament reconstruction (R-ACLR) represents a technically demanding procedure leading to lower clinical outcomes and reduced patient satisfaction compared to primary ACL reconstruction. The addition of lateral extra-articular tenodesis (LET) has been demonstrated to lower primary ACL reconstruction failure rates. The purpose of this study was to report a retrospective analysis of patients who underwent R-ACLR with or without LET with a minimum of 2 years follow-up. The hypothesis was that the addition of LET leads to higher patient-reported outcomes (PROMs) and a decrease in failure rate compared to isolated ACLR.

Methods

Seventy-four patients with a minimum of 2 years follow-up (range 24-120 months), who had a high-grade positive pivot shift test under anesthesia (= 2) were included. Postoperative radiologic measurements included medial posterior tibial slope (PTS) angle, lateral femoral condylar ratio (LFCR), and osteoarthrosis (OA) grade. Knee Injury and Osteoarthritis Outcome Score (KOOS) and the International Knee Documentation Committee (IKDC) Subjective Knee Form were collected. Failure criteria were defined as residual positive pivot test =2 during clinical assessment, objective knee instability symptoms, and/or postoperative MRI exam showing a complete graft tear. An ANCOVA was used to compare PROMs between groups, adjusted for patient age, study site and length of follow-up. Statistical significance was set at p<0.05 for all analyses.

Results

Thirty-nine patients underwent isolated R-ACLR (mean age (SD±) 29.2 ±12.2) and 35 had an additional LET (24.6 ±7.4). A first R-ACLR was performed in 84.6 % vs 82.8% respectively. Autologous extensor mechanism was the most common graft utilized (71.7 % vs 85.7%). One stage revision ACLR was performed in most cases (69.5%). Radiographic analysis showed a similar incidence of postoperative OA changes (KL grade =2) without a significant difference between the groups (43.6% vs 48.6% p = 0.67). The medial PTS° (mean ±SD) (9.6° ±3.1 vs 8.5° ±1.8 p = 0.05) and LFCR (mean ±SD) (0.64 ±0.03 vs 0.66 ±0.1 p = 0.24) measurement preoperatively were not significantly different. PROMs were higher in the LET group with KOOS ADL (93.5 ± 2.0 vs 97.2 ± 1.6; 0.03*) and KOOS Sport (63.0 ± 3.6 vs 74.3 ± 3.8; 0.049*) subdomains reaching statistical significance, with the latter reaching a minimum clinically important difference threshold. No other differences were found in the other KOOS subdomains or IKDC. No postoperative complications were found related to the addition of LET fixation on the lateral femoral condyle. Failure rates were not significantly different between the groups (12.8% vs 11.4%; p=0.99).

Conclusion

Revision ALCR with additional LET showed a similar failure rate compared to isolated R-ACLR in patients presenting with high-grade rotatory laxity following failed ACLR. Clinical outcomes suggested better functional results in the LET group with significantly higher activities of daily living, and sport and recreation KOOS subdomain scores. Additional studies should be performed with higher numbers of patients to investigate the potential protective effect of LET in revision ACLR patients.