یاسین حسینی

Aim and Background: The anterior cruciate ligament (ACL) rupture is one of the common injuries in sports. Optimum coordination of the lower limb muscles is required to prevent reoccurrence of ACL rupture. The purpose of this study was to compare the timing of lower limb's muscles in the stance phase of running between individuals with reconstructed ACL and healthy individuals. Methods and materials: In this study, surface EMG system was used to quantify the onset of the lower limbs’ muscles activities in 10 individuals with reconstructed ACL and 10 healthy subjects. Result: In ACL reconstructed individuals, the onset of the activity in tibialis anterior, medial gastrocnemius, vastus medialis, vastus lateralis, gluteus medius (P= 0.001) as well as the time to peak in tibialis anterior, vastus lateralis, vastus medialis, gluteus medius, semitendinosus (P= 0.001) and biceps femoris (P= 0.045) were delayed. Conclusion: During the stance phase of running, ACL reconstructed individuals displayed a delay on the activation onset, and a longer time to peak in the lower limb's muscles. It is not clear if these changes are due to a neuromuscular adaptation or proprioception related damage. A more comprehensive study is recommended to clarify this aspect. It is recommended to assess the possible link between this delay with reoccurrence of ACL rupture.