Age, sex and graft choice are associated with the achievement of a patient acceptable symptom state five years after primary ACL reconstruction

PURPOSE: To determine the proportion of patients and the factors associated with the achievement of a patient-acceptable symptom state (PASS) 5 years after primary anterior cruciate ligament reconstruction (ACLR). METHODS: Patients who underwent primary ACLR between 2005 and 2018 at Capio Artro Clinic, Stockholm, Sweden, were eligible for inclusion. The primary outcome was the achievement of a PASS on each Knee injury and Osteoarthritis Outcome Score (KOOS) subscale at the 5-year follow-up. Multivariable logistic regression analyses were used to assess associations with age, sex, time from injury to surgery, pre-injury Tegner activity level, graft type, cartilage injury, meniscal resection or repair, and symmetrical 6-month limb symmetry index (LSI ≥ 90%) in isokinetic extension and flexion strength and single-leg-hop performance. RESULTS: A total of 2663 patients were analysed. The proportion of patients achieving a PASS varied between the KOOS subscales as follows: Pain 64.8%; Symptoms 93.8%; Activities of Daily Living (ADL) 49.1%; Sport and Recreation (Sport 95% confidence interval CI 0.65-0.99; p = 0.04), Symptoms (OR 0.57; 95% CI 0.36-0.90; p = 0.02) and Sport CI 95% 0.59-0.90; p = 0.004) subscales. A surgical delay of ≥3 months was negatively associated with the achievement of a PASS on the QoL (OR 0.71; 95% CI 0.51-0.99; p = 0.04) subscale. Medial meniscus (MM) repair reduced the odds of achieving a PASS on the Sport 95% CI 0.41-0.92; p = 0.02) and QoL (OR 0.56; 95% CI 0.37-0.86; p = 0.01) subscales. Hamstring tendon (HT) autograft rather than bone-patellar-tendon-bone autograft had increased odds of achieving a PASS on the Sport 95% CI 1.31-3.47; p = 0.002) subscale. Achieving a LSI ≥ 90% in isokinetic extension strength was associated with a PASS on ADL (OR 1.01; 95% CI 1.00-1.02; p = 0.02) and QoL (OR 1.01; 95% CI 1.00-1.02; p = 0.02) subscales, whereas an LSI ≥ 90% in single-leg-hop test was associated with a PASS on the Symptoms (OR 1.03; 95% CI 1.01-1.05; p < 0.001), ADL (OR 1.01; 95% CI 1.00-1.02; p = 0.02), Sport 95% CI 1.01-1.02; p = .003), and QoL (OR 1.01; 95% CI 1.00-1.02; p = 0.01) subscales. CONCLUSION: The achievement of a PASS was over 64% on at least four out of five KOOS subscales 5 years after ACLR. Older age (≥ 30 years) was consistently associated with higher odds of achieving a PASS, while female sex was associated with lower odds. MM repair was associated with reduced odds of achieving a PASS on the Sport however, the effect sizes were small, suggesting limited clinical relevance. LEVEL OF EVIDENCE: Level III.