Manual stretch: effect on finger movement control and force control in stroke subjects with spastic extrinsic finger flexor muscles. A pilot study to investigate the effects of electrical stimulation on recovery of hand function and sensation in subacute stroke patients.
This study evaluated the effects of manual stretch of extrinsic finger flexor muscles on finger extension movement control and force control in 16 spastic hemiparetic subjects. These subjects were randomly divided into a control group and an experimental group. A group of able-bodied subjects also participated. A joint-movement tracking test (JMTT) quantified control of active finger extension movement at the metacarpophalangeal joint of the index finger within the available range of active movement, and a force tracking test (FTT) quantified control of isometric finger extension force at the same joint within the subject's available force range. Electromyographic activity was monitored in the extensor digitorum and flexor digitorum superficialis muscles during both tracking tests. Manual stretch was applied to the extrinsic finger flexor muscles of the experimental group between the pretest and posttest tracking tests. The JMTT performances of both control (p less than .025) and experimental (p less than .05) groups were significantly subnormal on the pretest as were FTT performances of controls (p less than .01) and study subjects (p less than .03). The JMTT improvement on posttest was significantly greater (p less than .05) in subjects than in controls. However, the change in FTT performance was not significantly different between the two groups. Manual stretch treatment, properly applied to extrinsic finger flexor muscles, is an effective method of temporarily improving the control of finger extension movement in spastic hemiparetic subjects. Objectives.  1) To compare the effect of cyclic neuromuscular electrical stimulation (NMES) of the forearm and elbow extensor muscles with passive stretching exercises on hand function and sensation following stroke. 2) To inform sample size for a larger randomized controlled trial (RCT). Materials and Methods.  Twenty-two subjects with hemiplegia resulting from a stroke during the previous 12 months were randomly allocated into stimulation (treatment) and exercise (control) groups. Stimulation was applied to the elbow, and forearm extensor muscle groups of the hemiplegic arm for 12 weeks. Subjects in the control group were taught passive stretching exercises for the same period. The primary outcome measure was the Action Research Arm test (ARAT). Sensation was tested using two-point discrimination. Statistical analysis applied nonparametric analysis of covariance (ancova). Results.  Statistically significant between-group differences in change in ARAT scores were shown between the two groups after 12 weeks of treatment (p = 0.003) and following 12 further weeks without intervention (p = 0.012). There were no significant differences in sensation. Conclusions.  1) A significant treatment effect of electrical stimulation over passive exercise has been demonstrated in a group of 22 subacute stroke patients, randomized into two equal groups and further work identified which may help to improve recovery of hand function and sensation following stroke. 2) A sample size of 24 subjects in each group has been estimated assuming a two-sided test significance level of 5% with 80% power, primary outcome variability SD = 6.75, a minimum difference of ten ARAT score units, and a 10% dropout rate.
Overall, the review demonstrated that the limited evidence of benefit of stretching, passive exercises and mobilization, when applied to the hemiplegic upper limb following stroke, merits further research.