Chronic stroke survivors may benefit from electrical stimulation

After a stroke, patients often lose muscle strength and require upper limb rehabilitation. Still, the best way to help patients recover depends on how long ago they had their stroke and on other factors.

A recent study suggests that contralaterally controlled functional electrical stimulation (CCFES) may be the preferable option for patients with finger, thumb and wrist issues who suffered a stroke less than two years ago. The researchers added that patients would likely not see improvement with cyclic neuromuscular electrical stimulation (cNMES) or CCFES if they suffered their strokes more than two years ago. Results were published in Stroke on Sept. 8.

The researchers enrolled 80 patients who had a stroke and had moderate to severe upper extremity hemiparesis for at least six months. Patients were randomized to receive 10 sessions per week of CCFES- or cNMES-assisted hand opening exercise at home as well as 20 sessions of functional task practice in the laboratory for 12 weeks.

After six months, the CCFES group had a greater improvement on the Box and Block Test (BBT), a measure of manual dexterity in which participants pick up one block at a time, move it over a partition and release it in a target area within 60 seconds.

“The finding of a statistically significant between-group difference on the BBT in a chronic population is encouraging and may point to a true mechanistic advantage underlying the CCFES method of electrical stimulation therapy,” the researchers wrote. “One or more of the elements that distinguish CCFES from cNMES may be important in facilitating motor recovery, namely, (1) real-time patient-controlled intensity of stimulation to the paretic hand (ie, intention-driven movement), (2) synchronized opening of both hands, and (3) stimulation-assisted task practice with the paretic hand. Thus, the method of NMES may matter.”

Still, the researchers mentioned that the average magnitudes of change on the BBT and the average between-group difference were lower than the minimum detectable change threshold. Thus, the results were not clinically relevant.

The study had some limitations, including that patients were aware of their treatment assignment and that the trial took place at one academic medical center in Cleveland, Ohio. The trial was also conducted at least six months after patients suffered their strokes, a period during which healthcare professionals do not typically prescribe rehabilitation. More work is needed to compare CCFES and cNMES, according to the researchers.

“Future trials should include validated patient reported outcomes and outcomes that are sensitive to participation and quality of life,” the researchers wrote. “Also, the translatability of CCFES therapy to other research sites and to clinical practice still needs to be established. A future multisite study is needed to confirm the findings of this study and to demonstrate generalizability across different rehabilitation centers.”