Effects of transcranial direct current stimulation on pain, isokinetic muscle strength, and balance function in patients with ankle fractures: a randomized-controlled clinical study

Aims: To investigate the efficacy of transcranial direct current stimulation (tDCS) combined with conventional rehabilitation interventions in improving pain scores, lower limb isokinetic muscle strength, balance, and motor control in patients with ankle fractures, thereby providing a clinical basis for optimizing central-targeted rehabilitation protocols for these patients. Methods: A total of 48 patients who had undergone ankle fracture surgery were enrolled and randomly divided into an observation group and a control group using a numerical table method, with 24 cases in each group. The control group received standard rehabilitation therapy for 6 weeks, while the observation group received additional tDCS intervention (20 minutes, 2.0 mA, stimulating the contralateral primary motor cortex) in addition to standard rehabilitation. Prior to and after intervention, various parameters were assessed using the isokinetic muscle strength testing system, TecnoBody balance testing system, Tinetti scale, three-dimensional gait analyzer, and VAS pain scale, including hip muscle strength, static and dynamic balance function, gait parameters, and pain levels in both groups. Results: All patients successfully completed all interventions and assessments without any severe adverse events. The relative peak torque of hip abduction and extension was significantly increased in all enrolled patients compared to pre-intervention levels, with the observation group showing significantly better results than the control group (p <0.001). Post-intervention, the Tinetti balance gait score significantly improved, while the center of gravity swing path length, swing area, and swing velocity were significantly reduced (p <0.05). The range of motion of the affected hip joint and step length parameters showed significant improvement (p <0.05). The VAS pain score decreased significantly compared to pre-intervention levels and remained significantly lower than that of the control group (p <0.05). Conclusion: tDCS can effectively alleviate pain symptoms in patients after ankle fracture surgery, enhance lower limb muscle strength, improve proprioceptive integration function, and significantly improve static balance, dynamic posture control, and gait performance. It effectively addresses postoperative functional impairments following ankle fractures, reduces the risks of falls and secondary injuries, and serves as a novel, highly effective intervention for rehabilitation following ankle fracture surgery.