Hamstring weakness at 90xf0b0; flexion of involved knee as an indicator of the function deficit in males after anterior cruciate ligament reconstruction (ACLR)

Purpose: The aim of this study was to elucidate predictors on knee function following anterior cruciate ligament reconstruction with hamstring tendon graft or allograft and to detect the differences between it and the healthy controls. Methods: This study comprised of 46 males, aged 18-45, being within 6-60 months following unilateral anterior cruciate ligament reconstruction and 50 healthy men. Measurements included the Tampa Scale for Kinesiophobia-17, the self-reported knee function with the Knee Injury and Osteoarthritis Outcome Score, Tegner activity scale and handheld dynamometry the hamstring/quadriceps femoris muscle testing at 90 degrees of flexion. Regression analyses were performed to predict the knee function in the anterior cruciate ligament reconstruction group. Results: The anterior cruciate ligament reconstruction group showed significantly lower Tegner activity and hamstring/quadriceps femoris strength, higher kinesiophobia and worse Knee Injury and Osteoarthritis Outcome Score ( p < 0.05). Their Knee Injury and Osteoarthritis Outcome Score-Sport/Recrection, Quality of Life and -Total values were modestly associated with the satisfaction with prior rehabilitation, activity level, graft type, kinesiophobia, time since the reconstruction and hamstring strength ( p < 0.05). The hamstring strength was the only important predictor of the Knee Injury and Osteoarthritis Outcome Score-Total ( p < 0.01). The involved knee handheld dynamometrymass normalize-hamstring strength at 90 degrees of flexion predicted 20.5% of the variance in the knee function. Conclusions: Presence of a decreased handheld dynamometry-mass normalized-hamstring strength result at hyper-flexion after anterior cruciate ligament reconstruction in men may indicate self-reported knee function disorder.