Self-reported outcomes are associated with knee strength and functional symmetry in individuals who have undergone anterior cruciate ligament reconstruction with hamstring tendon autograft

Abstract

BackgroundThe aim of this study was to investigate the relationship between self-reported knee outcomes and limb symmetry indices (LSIs) for hip and knee strength, postural control and single-leg hop distance in individuals who had undergone an anterior cruciate ligament (ACL) reconstruction via hamstring tendon autograft (HTG). MethodsA total of 72 participants with a history of unilateral ACL reconstruction via HTG (mean ± standard deviation (SD) age: 28.0 ± 7.6 years; height: 178.4 ± 6.7 cm; mass 76.9 ± 14.9 kg) were included. International Knee Documentation Committee 2000 Subjective Knee Form (IKDC), Lysholm, Knee Osteoarthritis Outcomes Scores (KOOS) and Tampa scores were used to evaluate self-reported outcomes. Concentric and eccentric knee extensor and flexor, and hip strength, postural control and single leg hop distance were evaluated for performance-based outcomes. The relationships between the LSI scores and the performance measures were explored using the Pearson correlation coefficient. ResultsThe IKDC, Lysholm and KOOS scores were positively correlated with knee extensor and flexor strength LSIs (P < 0.05, r = 0.34 to r = 0.50), and the Tampa score was negatively correlated with eccentric extensor LSI (P = 0.02, r = −0.34). Single-leg hop distance LSI was correlated with IKDC and Lysholm scores (P = 0.003, r = 0.50; P = 0.04, r = 0.29) respectively, while postural control was only correlated with the KOOS scores (P < 0.001, r = 0.51 to r = 0.52). ConclusionsCompared to Lysholm and Tampa scores, KOOS and IKDC scores were more likely to be correlated with performance-based outcomes. Therefore, KOOS and IKDC scores may help clinicians in return to sport decision making when there is a limited time to perform extensive evaluations or access equipment.