The effect of rehabilitation exercises on time series correlation in gait of anterior cruciate ligament deficient patients

In this research the effect of perturbation training on correlation index of detrended fluctuation analysis index (α) of anterior cruciate ligament (ACL) patients was evaluated using nonlinear dynamic methods. The study was done on ten male athletes with at least 6 months elapsed after their ACL lesions. Subjects were selected using non-probability sampling technique. Stride time for about 270 gait cycles for each patient was recorded and used for detrended fluctuation analysis. Analysis showed difference in values of α between primary and shuffled data which indicates a non-trivial trend of data structure. According to the range of α (0.5>α>1), long time correlation between gait cycles was found. Also, the results showed no significant difference on α before and after training (p=0.515). The results showed persistent patterns in time series which are similar to slow speed walking patterns. Also, it can be concluded that, according to their correlation values, ACL deficient patients had a similar behavior to healthy people.