Integrating multi-session transcranial direct current stimulation with routine physical therapy to improve quadriceps strength and activation in athletes during subacute recovery following ACL reconstruction: A double-blind RCT.

Study Summary

20 non-professional male athletes undergoing subacute rehabilitation after anterior cruciate ligament reconstruction (ACLR) were randomized to receive active anodal transcranial direct current stimulation (a-tDCS) plus routine physical therapy (RPT) or sham a-tDCS plus RPT. Both groups received 10 stimulation sessions during RPT, with active stimulation delivered at 2 mA for 20 minutes and sham stimulation discontinued after 30 seconds. The primary outcomes of interest were quadriceps voluntary activation, measured using the Central Activation Ratio (CAR), and quadriceps strength, measured as normalized peak torque during maximal voluntary isometric contraction. Secondary outcomes included the International Knee Documentation Committee (IKDC) score, Knee injury and Osteoarthritis Outcome Score (KOOS), visual analogue scale (VAS) pain score, and ACL-Return to Sport after Injury (ACL-RSI) score. Outcomes were assessed at 10 weeks after ACLR and after completion of the 10-session intervention. Overall, the results of the study revealed that active a-tDCS significantly improved voluntary activation compared with sham stimulation, while no significant between-group difference was found for quadriceps strength. Active a-tDCS also improved IKDC scores, suggesting that adding neuromodulation to RPT may enhance central quadriceps activation and knee-specific functional recovery during subacute ACLR rehabilitation.