Outcomes of ACL Reconstruction with Quadriceps Tendon Graft Based on Graft Diameter Relative to Notch Width.

Background: While quadriceps tendon (QT) autograft is being increasingly utilized for primary anterior cruciate ligament reconstruction (ACLR), there remains limited evaluation of how QT autograft diameter and the ratio of graft diameter to femoral notch width (D-N ratio) affect clinical outcomes, such as rates of symptomatic knee stiffness or revision ACLR.

Hypothesis: Larger QT autograft diameter and D-N ratio would be associated with higher rates of subsequent surgery for knee stiffness, whereas a smaller QT autograft diameter and D-N ratio would be associated with higher rates of revision ACLR.

Study design: Cohort study; Level of evidence, 3.

Methods: All consecutive patients age ≥14 years who underwent primary QT autograft ACLR between 2011 and 2021 were analyzed. Exclusion criteria were <6-month follow-up, double-bundle ACLR, and concomitant procedures other than meniscal repair. Rates of subsequent surgery for knee stiffness and revision ACLR were evaluated at minimum 6-month and 24-month follow-up, respectively. Demographic and surgical variables were compared between knee stiffness and revision ACLR groups. Significance was set to P < .05.

Results: A total of 374 patients (mean ± SD age, 22 ± 7 years; 42% female) met inclusion criteria, of which 209 patients (mean age: 23 ± 7 years; 49% female) had minimum 24-month follow-up. The rate of subsequent surgery for knee stiffness was 9.9% (37/374 patients), and the rate of revision ACLR was 9.6% (20/209 patients). Lateral meniscal repair (odds ratio [OR], 2.5; 95% CI, 1.2-5.2; P = .02) and D-N ratio >0.55 (OR, 3.4; 95% CI, 1.2-9.7; P = .02) were identified as independent predictors of subsequent surgery for knee stiffness. There was no significant difference in QT autograft diameter (9.2 vs 9.5 mm; P = .17), femoral notch width (17.3 vs 17.7 mm; P = .64), nor D-N ratio (0.54 vs 0.54; P = .87) between patients who underwent revision ACLR versus no revision ACLR.

Conclusion: D-N ratio >0.55 and concomitant LM repair were associated with significantly higher odds of undergoing subsequent surgery for knee stiffness after QT autograft ACLR. Conversely, QT autograft diameter and D-N ratio were not associated with undergoing revision ACLR. Avoiding overstuffing of the femoral notch may reduce risk of subsequent surgery for knee stiffness without increasing the risk of undergoing revision ACLR.