The effect of transcranial direct current stimulation on pain, range of motion, and balance in sportspersons with ankle sprain: a randomized controlled trial

Introduction
Ankle sprains are the most common sports injury. Injury to ankle joint causes local as well as distant defects in the central nervous system. The interventions that modulate defects centrally, as well as peripherally, can be of great significance in treating the condition. Aims and objectives: The present study aims to estimate the effects of transcranial direct current stimulation on pain, range of motion, and balance in players with ankle sprain.

Material and methods
The present study was a randomized, controlled participant blinded trial. Twenty players aged between 16 to 30 years with a history of ankle sprain were recruited and were assigned in two groups. Group A received active tDCS stimulation and Group B received sham stimulation of 2mA for 20 min for five consecutive days. The outcome variables were pain (VAS), range of motion at the ankle joint, and balance measured by the Y-balance test measured at the baseline and post-intervention.

Results
There was a significant reduction in pain (p = 0.039) and significant improvement in range of motion in dorsiflexion (p = 0.043) and plantarflexion (p = 0.019) at the ankle joint when between-group comparisons were done. Whereas, no significant improvement in balance (p = 0.502) was observed when between-group comparisons were done.

Conclusions
The application of tDCS is effective in decreasing pain and improving range of motion, but ineffective for improving balance in players with ankle sprains. To improve the balance, foot exercises can also be added along with the tDCS to improve the treatment outcomes in players with ankle sprains.