The effectiveness of low-frequency transcranial magnetic stimulation for restoring upper limb function after cerebral infarction / 中华物理医学与康复杂志

ABSTRACT

Objective To compare the effects of repetitive transcranial magnetic stimulation (rTMS) at various low frequencies on upper limb function after cerebral infarction.Methods Fifty patients were randomly assigned to a control group (10 cases),a sham rTMS group (10 cases) or an rTMS group which had three sub-groups treated at 0.25 Hz,0.5 Hz and 0.75 Hz with 10 cases in each.All of the patients were treated with conventional medical treatment and rehabilitation training.The sham and true rTMS groups received rTMS applied over the M1 area of the unaffected hemisphere,5 days per week for 4 weeks.Motor evoked potential (MEP) cortical latency,and central motor conduction time (CMCT) were measured and the Fugl-Meyer assessment (FMA),motricity index (MI) and a Hong Kong functional test for the hemiplegic upper extremity (FTHUE-HK) were evaluated beforehand and at Post 1 after 2 weeks of treatment and Post 2 after 4 weeks of treatment.Results The average CMCT and FMA scores of the control and sham rTMS groups both had improved significantly at Post 2.There was no significant difference in any of the indices between those 2 groups at any time point.At Post 1,the average MEP cortical latencies of the 0.25 Hz and 0.5 Hz subgroups had improved to be significantly better than those of the control and sham rTMS groups.The average CMCTs of the 0.25 Hz and 0.5 Hz rTMS subgroups were significantly shorter after treatment,and significantly better than those of the control and sham rTMS groups.At Post 2,the average MEP cortical latency of all groups except the control group showed significant improvement compared with pre-treatment.The 2 indices of the 0.25 Hz and 0.5 Hz subgroups were again significantly shorter than those of the control and sham rTMS groups,and the average CMCTs were significantly better than that of 0.75 Hz subgroup.At Post 1 the average FMA and MI scores of the rTMS subgroups had all improved significantly.In the 0.25 Hz and 0.5 Hz subgroups the average MI scores were significantly higher than those of the control and sham rTMS groups.The FTHUE-HK scores of those 2 subgroups had also improved significantly.At Post 2,the average FMA and MI scores of all groups and the FTHUE-HK scores of rTMS group had improved significantly.In the 0.25 Hz and 0.5 Hz subgroups,all of the indices were significantly better than in the control and sham rTMS groups.The average FTHUE-HK score of the 0.25 Hz subgroup was significantly superior to that of the 0.75 Hz subgroup.In the 0.75 Hz subgroup the average MI score was significantly higher than in the control and sham rTMS groups.Conclusions rTMS at either 0.25 Hz or 0.5 Hz applied to the unaffected hemisphere provides effective treatment for enhancing the excitability of the motor cortex and the motor function of a paretic upper limb after stroke.Compared with others,the total number of stimulus pulse in 0.25 Hz subgroup was the least,and priority consideration should be given to the frequency of 0.25 Hz when using rTMS in clinical treatment of cerebral infarction.