Comparing the effects of transcutaneous electrical nerve stimulation and microcurrent electrical stimulation after total knee arthroplasty

[Purpose] To compare the effects of transcutaneous electrical nerve stimulation and microcurrent electrical stimulation on pain relief and knee function following total knee arthroplasty．[Participants and Methods] This was a prospective, single-center, 3-group parallel study. Thirty-five patients scheduled for total knee arthroplasty were divided into the transcutaneous electrical nerve stimulation, microcurrent electrical stimulation, and control groups. Interventions began on postoperative day three and continued for two weeks. Pain intensity during walking, maximum walking speed, timed up-and-go test, and isometric knee extension strength were evaluated before and 2 and 4 weeks after surgery. Statistical analyses were performed using a mixed-effects model for repeated measures with split-plot analysis and preoperative pain catastrophizing score as a covariate.[Results] Two weeks after surgery, pain during walking was lower in the transcutaneous electrical nerve stimulation group than in the other groups, and maximum walking speed was faster than in the microcurrent electrical stimulation group. Timed up-and-go and isometric knee extension strength improvements were observed over time but were not significantly different between the groups.[Conclusion] Transcutaneous electrical nerve stimulation effectively relieved pain and improved walking speed early after total knee arthroplasty, whereas microcurrent electrical stimulation did not show significant benefits compared to the control.