The Effect of Intramuscular Low Frequency Electrical Stimulation for Hemiplegic Shoulder Pain

Objective: To investigate the effects of intramuscular low frequency electrical stimulation on shoulder pain in hemiplegic patients. Method: Twenty five hemiplegic shoulder pain patients were divided into two groups. For experimental group, we inserted stainless steel acupuncture needle on the motor points of supraspinatus, infraspinatus, trapezius and middle deltoid muscle and applied intramuscular electric stimulation (4 Hz, unsymmetric spike pulse, 2.0 ms of pulse width) for twenty minutes, three sessions a week, in total 10 sessions. For control group, we applied transcutaneous electrical nerve stimulation for twenty minutes. Visual analog scale(VAS), passive range of motion of shoulder joint, and Korean version of modified Barthel index (K-MBI) were measured before and after the treatment. Results: The VAS of experimental group significantly decreased from 7.23 +/- 0.83 to 3.04 +/- 1.52, while control group showed a slight decrease from 7.50 +/- 0.70 to 5.64 +/- 0.74. The experimental group showed significant improvement compared to the control group (p < 0.05). In the experimental group, there were significant improvements in motion of abduction from 103.6 +/- 20.5 to 134.0 +/- 32.3 and external rotation from 60.0 +/- 19.6 to 68.6 +/- 19.7 (p < 0.05) even though there were no significant differences between the two groups. Conclusion: Intramuscular low frequency electrical stimulation improved pain as well as the range of motion. This could be used for the treatment of hemiplegic shoulder pain.