A Study of Different Frequencies of Repetitive Transcranial Magnetic Stimulation on Upper Extremity Muscle Activity and Hand Function in Chronic Stroke Patients

The purpose of this study was to compare the use of different frequencies of repetitive transcranial magnetic stimulation (rTMS) on the upper extremity muscle activity and hand function of chronic stroke patients. The study subjects comprised 18 chronic stroke patients: the 5 Hz rTMS group (HFG), which included nine patients who received rTMS to the affected cerebral hemisphere, and the 1 Hz low-frequency group (LFG), which had nine patients who received rTMS to the nonaffected cerebral hemisphere. The intervention was conducted three times a week for four weeks. Electromyography was used to check muscle activity, and the stroke upper extremity function test (MFT) and grip strength test were performed to check hand function. Pre- and post-evaluations were performed for both groups. A comparison between the two groups showed a significant difference in the activity of the trapezius anterior and triceps brachii muscle for the muscle activities in the HFG group (p < 0.05) as well as a significant difference in the MFT results for hand function (p < 0.05). In the LFG group, a significant difference was noted in the triceps brachii muscle for muscle activity (p < 0.05), but no significant difference was evident in hand function (p > 0.05). The comparison of the two groups showed a significant difference in muscle activity in the triceps brachii muscle (p < 0.05) but no significant difference in hand function (p > 0.05). This study confirmed that high-frequency rTMS has a positive effect on upper extremity muscle activity and hand function in chronic stroke patients.