The Effect of Rehabilitation Exercises on Time Series Correlation in Gait of Anterior Cruciate Ligament Deficient Patients

Objective: In this research the effect of perturbation training on correlation index of detrended fluctuation analysis index (;alpha) of anterior cruciate ligament deficient (ACL) patients was evaluated using nonlinear dynamic methods. Materials & Methods: The study was done on ten male athletes with at least 6 months elapse 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. Results: Analysis showed difference in values of ;alpha between primary and shuffled data which indicates a non-trivial trend of data structure. According to the range of ;alpha (0.5>;alpha>1), long time correlation between gait cycles was found. Also, the results showed no significant difference on ;alpha before and after training (P=0.515). Conclusion: 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.