Proprioception in individuals with ACL-deficient knee and good muscular and functional performance

The objective of this study was to verify whether proprioception is affected in individuals with ACL-deficient knees and good functional and muscular performances. Eleven subjects with ACL injury and 11 controls participated in the study. Functional performance was assessed using the Cincinnati Knee Rating System (CKRS), hop index, and figure-eight ratio. An isokinetic test was done to evaluate muscular performance. Proprioception was evaluated through position, sense and threshold tests. Analyses of variance were used for data analysis. The injured subjects scored significantly lower in the CKRS (p = 0.001). No statistically significant differences were found in the hop index, in the figure-eight ratio, or in peak torque. There were no statistically significant differences in proprioception bettween groups and between legs. These results indicated that the individuals evaluated in this study with ACL injury and good functional and muscular performance did not have proprioceptive deficits, suggesting that the ligament mechanoreceptors, in some cases, might not contribute relevantly to proprioception.