Critcally Appraised Paper for: “Is modified constraint-induced movement therapy more effective than bimanual training in improving arm motor function in the subacute phase post stroke? A randomized controlled trial.”
Patients poststroke compose one of the largest demographics treated by occupational therapists in the physical disability setting. Approximately two-thirds of individuals who have had a stroke present with arm function impairment (Kwakkel & Kollen, 2007). Therefore, effective arm rehabilitation in occupational therapy settings is critical to help patients regain functional independence and quality of life. Modified constraint-induced movement (MCIM) therapy has been reported as the superior method of arm rehabilitation for individuals in the subacute phase poststroke, although recent research has also supported bimanual training. This 4-week, randomized controlled, quantitative study compared the effect of MCIM therapy and bimanual task-related training for 30 poststroke participants in the subacute phase.
The intervention approach for the two groups incorporated activities of daily living, each with a unique rehabilitative focus. Although both groups received task-related training with a therapist 4 hr each week for 4 weeks, the MCIM therapy had a unilateral focus, whereas the bimanual training had a bilateral focus. Participants in the MCIM therapy group were asked to wear a mitt on their unaffected limb 4 hr/day, and participants in the bimanual group were encouraged to use both limbs together in bimanual tasks. All participants were required to complete and record 2–3 hr of self-training daily
Results indicated that both the MCIM therapy and the bimanual training participants improved in functional tasks and motor skills of the affected arm within their group, but no statistical difference was identified between the groups. Thus, the researchers concluded that MCIM therapy was no more effective than bimanual training to improve arm function among patients in the subacute phase poststroke. They determined that further comparison was unnecessary, because any difference in effectiveness would not be clinically relevant.
Application of these conclusions in occupational therapy settings, however, must be considered carefully in light of the small sample size. The initial power calculation necessitated a sample size of 60 participants, yet only 30 participants were obtained. Furthermore, this study lacked a control group, relied on self-report, and contained a number of biases. Site bias and cointervention bias could not be avoided, because participants resided in various settings and might have received other forms of rehabilitation. Timing bias was likely, because 4 weeks was an insufficient time frame to demonstrate the effect of an intervention on motor function recovery. Contamination might have occurred, given that the MCIM therapy group wore the mitt only 4 hr/day and that bimanual use for tasks at other times of the day could not be prevented.
On the basis of the methodological limitations of the study, the conclusion drawn by the authors that the two intervention methods were equally effective in improving motor arm function in the subacute phase poststroke cannot be supported. Further research comparing the two interventions is recommended. With no method demonstrating clear superiority in this study, occupational therapists should consider every client individually when determining whether MCIM or bimanual training would be an appropriate intervention.
Copyright © 2016 American Occupational Therapy Association. All Rights Reserved. Reproduced here with permission.
Originally published as: Ichimaru, J., Sik, J., Findlay, K., & Li, K. (2017). “Is modified constraint-induced movement therapy more effective than bimanual training in improving arm motor function in the subacute phase post stroke? A randomized controlled trial.” Clinical Rehabilitation, 26(12), 1078-1086. Bethesda, MD: American Occupational Therapy Association, Evidence-Based Practice Project.