| Objective To determine the immediate therapeutic effect of manual digitorum sensory stimulation（MDSS）on hemiplegic upper limb function and the duration of one stimulation,and to analyze its effect on surface electromyography（s EMG）and brain function.Methods A total of 30 patients with hemiplegic flexor spasm after initial stroke were selected,underwent MDSS completed by a researcher who used a bare thumb and index finger to squeeze each nail bed as well as the sides of each fingertip in the affected hand once each.The stimulation intensity was the minimum intensity that could cause finger extension but not obvious pain,and the interval between two stimulations was 5～10seconds on the basis of routine rehabilitation treatment.The modified Ashworth scale（MAS）and manual muscle testing（MMT）were used to evaluate the muscle tension and muscle strength of extensor digitorum,flexor digitorum,pronator,supinator,triceps and biceps on the affected side of each hemiplegic stroke patient before stimulation,immediately after stimulation,15 minutes,30 minutes and 45 minutes after stimulation.At the same time,the root mean square（RMS）of abductor pollicis brevis,dorsal interosseous muscle,abductor Digiti minimi,extensor digitorum,flexor digitorum,triceps brachii,biceps brachii during maximal isometric contraction（MIVC）on the affected side of each hemiplegic stroke patient and motor evoked potentials（MEP）in M1 area of healthy and affected sides were collected before stimulation,immediately after stimulation and 15 minutes after stimulation.The MAS scores,MMT scores,RMS value,MEP latency and amplitude of the tested muscles at each time point before and after stimulation were statistically analyzed.Results1.The MAS scores of muscle groups examined by immediately,15 min and 30 min after stimulation were lower than those before stimulation.Except for extensor Digiti minimi,the MAS scores of other muscle groups examined by 45 min after stimulation was lower than that before stimulation.There were significant differences in MAS scores of flexor digitorum（thumb/middle finger/little finger）,triceps brachii and biceps brachii at each time point before and after stimulation（all P<0.05）.Among them,there were significant differences in MAS scores of flexor digitorum（thumb/middle finger）between immediately after stimulation and before stimulation,between 30 min after stimulation and immediately after stimulation,between 45 min after stimulation and immediately after stimulation;there were significant differences in MAS scores of flexor digitorum（little finger）between immediately after stimulation and before stimulation,between45 min after stimulation and immediately after stimulation;there were significant differences in MAS scores of triceps muscle between immediately after stimulation and before stimulation and between 45 min after stimulation and immediately after stimulation;there were significant differences in MAS scores of biceps brachii between immediately after stimulation and before stimulation.2.There was no significant difference in MMT scores at each time point before and after stimulation of the tested muscle groups（all P>0.05）.3.Except for abductor pollicis brevis,the RMS value of all tested muscle groups immediately after stimulation and 15 minutes after stimulation was higher than that before stimulation,while the RMS value 15 minutes after stimulation was lower than that immediately after stimulation.There were significant differences in RMS value of abductor pollicis brevis,dorsal interosseous muscle of first bone,extensor digitorum and flexor digitorum before stimulation,immediately after stimulation,and 15 minutes after stimulation（all P<0 05）.There were significant differences in RMS value of abductor pollicis brevis,extensor digitorum and flexor digitorum between immediately after stimulation and before stimulation and between 15 min after stimulation and immediately after stimulation.There were significant differences in RMS value of dorsal interosseous muscle of first bone between immediately after stimulation and before stimulation.4.There were significant differences in the amplitude and latency of MEP on the healthy side before stimulation,immediately after stimulation,and 15 minutes after stimulation（all P<0.05）.Among them,there were significant differences in the amplitude and latency of MEP between immediately after stimulation and before stimulation;there were significant differences in the amplitude of MEP between 15 min after stimulation and before stimulation;there were significant differences in the latency of MEP between 15 min after stimulation and immediately after stimulation.The amplitude of MEP in the healthy side immediately after stimulation and 15 minutes after stimulation was higher than that before stimulation,and the latency was lower than that before stimulation.Compared with immediately after stimulation,the amplitude of MEP on the healthy side decreased and the latency prolonged 15 minutes after stimulation.Conclusions1.MDSS can immediately and effectively alleviate the spasm of flexor digitorum muscles,improve the muscle strength of upper limb muscle groups and promote to actively extend fingers on the hemiplegic side of stroke patients.2.The efficacy of single stimulation can last for at least 30 minutes.3.Surface EMG signal can record the EMG characteristics in real time during the dynamic activity of muscles,and then evaluate the functional state of muscles objectively and quantitatively.4.MDSS on hemiplegic side can promote the remodeling of neural structure and function after stroke,increase the cortical excitability of healthy cerebral hemisphere,and then improve the function of upper limb. |
