Abstract
OBJECTIVE: This study explored the association between knee crepitus and the presence, and worsening, of structural osteoarthritis features and self-reported outcomes in young adults following traumatic knee injury. METHODS: One year following anterior cruciate ligament reconstruction (ACLR), 112 participants (41 female participants; median age 28 years old) self-reported the presence and/or absence of knee crepitus using an item from the Knee Injury and Osteoarthritis Outcome Score (KOOS). Patellofemoral and tibiofemoral osteoarthritis features (ie, cartilage lesions, osteophytes, and bone marrow lesions) were assessed from magnetic resonance imaging scans at one and five years after ACLR. Self-reported outcomes were assessed with two KOOS subscales (pain and quality of life [QoL]) and the International Knee Documentation Committee subjective evaluation form (ie, self-reported function). Poisson regression evaluated the relationship between self-reported crepitus and the presence/worsening of structural osteoarthritis features. General linear models explored the relationship between crepitus and self-reported outcomes. RESULTS: Self-reported crepitus was associated with full-thickness patellofemoral cartilage lesions one year after ACLR (prevalence ratio 2.70, 95% confidence interval [CI] 1.41-6.39) but not the risk of worsening structural osteoarthritis features between one and five years after ACLR. Those with crepitus reported worse pain (β = -6.42, 95% CI -10.47 to -2.36), QoL (β = -10.39, 95% CI -18.58 to -2.20), and function (β = -5.49, 95% CI -10.92 to -0.06) one year after ACLR but greater improvement in pain and function between one and five years. CONCLUSION: Self-reported knee crepitus was associated with the presence of full-thickness patellofemoral cartilage defects one year after ACLR but was not associated with a greater risk of worsening structural osteoarthritis features up to five years after ACLR. One year after ACLR, those with crepitus reported worse pain, knee-related QoL, and function.