Effect of Transcranial Direct Current Stimulation at the Left Dorsolateral Prefrontal Cortex Combined With Quadriceps Strengthening Exercise in Chronic Knee Osteoarthritis: A Double-Blind, Randomized, Sham-Controlled Trial.

OBJECTIVE

The aim of the study was to study the effect of transcranial direct current stimulation on the left dorsolateral prefrontal cortex plus exercise on pain, function, and quality of life in chronic knee osteoarthritis.

DESIGN

Thirty-two participants with chronic knee osteoarthritis were randomly assigned to real transcranial direct current stimulation (anode: left dorsolateral prefrontal cortex, cathode: right supraorbital, 2 mA for 20 mins) or sham treatment, with quadriceps exercises three times weekly for 4 wks. Visual analog scale, pressure pain threshold, and the Western Ontario and McMaster University Osteoarthritis Index, and Short Form Health Survey-36, were assessed at baseline, posttreatment, and 4 wks later.

RESULTS

No significant differences were found between groups in any outcome after completing 12 sessions (mean difference [95% CI]: visual analog scale -0.30 [-9.49, 8.89]; pressure pain threshold 0.033 [-0.039, 0.105]; Western Ontario and McMaster University Osteoarthritis Index 4.22 [-3.35, 11.79]; Short Form Health Survey-36 -0.44 [-6.23, 5.35]) or at follow-up (visual analog scale 0.01 [-15.69, 15.71]; pressure pain threshold 0.008 [-0.113, 0.130]; Western Ontario and McMaster University Osteoarthritis Index 4.91 [-7.56, 17.37]; Short Form Health Survey-36 -2.96 [-12.11, 6.20]).

CONCLUSIONS

The findings showed that transcranial direct current stimulation over the left dorsolateral prefrontal cortex provided no significant additional benefit to quadriceps exercise compared to sham stimulation in improving pain, function, or quality of life in individuals with chronic knee osteoarthritis.