Graft Failure Rate Is Similar Between Groups With and Without Increased Posterior Tibial Slope After Primary Anterior Cruciate Ligament Reconstruction With Lateral Extra-articular Tenodesis.

PURPOSE: To evaluate the clinical outcomes of patients with increased posterior tibial slope (PTS ≥12°) undergoing primary anterior cruciate ligament reconstruction (ACLR) with concomitant lateral extra-articular tenodesis (LET) and to determine whether the addition of LET mitigates the elevated risk of graft failure associated with increased tibial slope.

METHODS: This single-center retrospective cohort study included patients ≥16 years who underwent primary ACLR with LET between 2013 and 2022 with a minimum 2-year follow-up. Patients were stratified by PTS ≥12° versus <12° and required preoperative lateral radiographs for slope measurement and high-risk features (pivot shift ≥2, Beighton ≥4, or return to pivoting sports). Outcomes included graft failure, residual pivot shift, complications, and patient-reported outcomes (International Knee Documentation Committee and Lysholm). Achievement of minimal clinically important difference was assessed. Multivariable logistic regression and Cox proportional hazards analysis were performed to identify independent predictors of graft failure.

RESULTS: A total of 289 patients (mean follow-up, 38 months) were included: 45 with PTS ≥12° (13.0° ± 1.2°) and 244 with PTS <12° (8.1° ± 1.5°). Graft failure occurred in 24% versus 18%, respectively (P = .411). On multivariable Cox proportional hazards analysis, no independent predictor of graft failure was identified, including PTS (hazard ratio, 1.07 per degree; 95% confidence interval, 0.95-1.19; P = .260). Complications and contralateral anterior cruciate ligament injury rates were similar between groups. On sex-disaggregated analysis, similar patterns were observed in both male and female cohorts, with no significant between-group differences in graft failure, retear, or complication rates by tibial slope. Patient-reported outcomes were comparable at all time points. At final follow-up, minimal clinically important difference achievement for International Knee Documentation Committee and Lysholm was 98% and 100%, respectively, with no between-group differences.

CONCLUSIONS: In high-risk patients with a PTS of ≥12°, primary ACLR with LET led to similar clinical results as patients with a PTS of 12 or less. A PTS of ≥12° may be considered an indication for the addition of an LET during primary ACLR.

LEVEL OF EVIDENCE: Level III, retrospective comparative case series.