The Effect of Repetitive Transcranial Magnetic Stimulation on Upper Extremity Motor Function in Stroke Patients: A Meta-Analytical Review

Repetitive magnetic stimulation (iTMS) is a non-invasive brain stimulation technique, which can alter excitability in the motor cortex and is a potential treatment for motor impairment in stroke patients. However, the effect of rTMS on upper extremity function in stroke patients remains controversial. This study systematically reviewed and meta-analyzed the current findings on the effectiveness of rTMS for restoring upper extremity motor function in stroke patients. A comprehensive literature search up to March 2010 of PubMed, the Cochrane Library, Scirus and the Chinese Electronic Periodical Services (CEPS) was performed. The articles from these searches were used to obtain additional articles. The quality of each study was assessed by criteria suggested by Jadad and the American Academy of Neurology for grading therapeutic trials. Biostat meta-analysis software version 2.0 was used to perform meta-analysis. Nine studies were included. The overall random effects model revealed a significant positive treatment effect of rTMS when applied to primary motor cortex (M1) (Hedges' g = 0.590, 95% CI = 0.133 - 1.048, p = 0.011). In subgroup analysis, positive treatment effects were seen in acute stroke (Hedges' g = 0.91, 95% CI = 0.339 - 1.481, p = 0.002) and on the nonlesional M1 cortex (Hedges' g = 0.807, 95% CI = 0.054 - 1.560, p = 0.036). It is concluded that when applied to the nonlesional hemisphere, low frequency rTMS may improve the upper extremity motor function of patients with acute stroke.