Contralaterally Controlled Functional Electrical Stimulation for Improving Motor Function After Acquired Brain Injury: A Systematic Review and Meta-analysis.

After a stroke, weakness on one side of the body often makes it hard to move an arm or leg with normal control, and clinicians have looked to electrical stimulation devices as a way to help retrain movement. This review focuses on a specific type called contralaterally controlled functional electrical stimulation, which uses movement from the unaffected side to trigger stimulation on the affected side, and compares it against usual rehabilitation or standard electrical stimulation in people recovering from stroke. Pooling data from 24 randomized trials with over a thousand participants, the review found that this approach was associated with greater improvements than the comparison treatments across several measures, including motor function scores, joint range of motion, ability to perform daily activities, muscle strength testing, muscle activity readings, and walking ability.

However, no statistically significant difference was found for a hand and arm dexterity test. The main limitation is that all included studies involved stroke patients, so it remains unclear whether these findings extend to other types of brain injury, and the authors call for more standardized trials.

If you or someone you know is recovering movement after a stroke, you may have come across electrical stimulation therapies as part of rehabilitation. This review looked at one particular version, where a device uses movement detected in the unaffected arm or leg to trigger stimulation in the affected limb, helping it move along with the healthy side.

Researchers combined results from 24 studies involving more than a thousand stroke survivors to see whether this approach helped more than standard rehabilitation or ordinary electrical stimulation. The combined evidence suggested that people using this stimulation approach tended to show greater improvements in several areas, including overall motor function, range of motion, daily activity performance, muscle strength, muscle activity, and walking ability, compared with those receiving standard treatment. However, no clear difference was found on a specific test of arm and hand dexterity.

It is also important to know that all the included studies involved people recovering from stroke, so it is not yet known whether these results would apply to people with other kinds of brain injury.

This is a summary of research, not medical advice. Talk to your own healthcare provider about anything affecting your care.

This systematic review and meta-analysis pooled 24 randomized controlled trials, comprising 28 intervention-control comparisons and 1,148 participants, all with stroke, evaluating contralaterally controlled functional electrical stimulation against routine rehabilitation or conventional electrical stimulation. Statistically significant between-group improvements favoring the intervention were found across multiple outcomes: Fugl-Meyer Assessment (standardized mean difference 0.66, 95% confidence interval 0.44 to 0.88), active range of motion (0.77, 0.54 to 1.01), modified Barthel Index (0.55, 0.29 to 0.81), Motricity Index (0.60, 0.26 to 0.94), surface electromyography (0.81, 0.56 to 1.06), and Functional Ambulation Category (0.53, 0.24 to 0.83).

No statistically significant difference was detected for the Action Research Arm Test (0.24, -0.10 to 0.58, p=.17), indicating uncertain benefit for upper limb dexterity specifically. The abstract does not report pooled heterogeneity statistics or formal risk-of-bias grading, so confidence in individual outcome estimates cannot be fully appraised from this summary alone. All trials were conducted in stroke populations, limiting generalizability to other acquired brain injuries, and the authors themselves call for further trials and standardization of protocols before firmer conclusions can be drawn.