Constraint-induced Movement Therapy

Constraint-Induced Aphasia

Constraint-induced Movement Therapy (CIMT) is typically used to help people who have a weakness on one side of their body. It is based on three main principles: first, you are not allowed to use your good hand or leg; this is restricted or constrained by a mitt, a splint or a sling. Second, you are forced to use your weak limb. Third, you have to use your weak limb all day every day, not just during the therapy. CIMT is grounded in the idea that the brain is ‘plastic’ and capable of change and reorganisation after a serious injury. Researchers at the University of Alabama have supported this by measuring changes in the structure of the brain that correspond to such increases in movement. They explain:

‘Structural brain changes paralleled these improvements in spontaneous use of the more impaired arm for activities of daily living. There were
profuse increases in gray matter in sensory and motor areas…’1

By using your weak limb, your brain is forced to make new connections and
create new brain maps. This approach has been successful for a number of
conditions, including cerebral palsy and stroke. The best selling author
Norman Doidge2 describes the therapy:

Induced movement therapy

Man with arm sling

‘Edward Taub developed a therapy for strokes which basically does the following: the assumption is that when you have a stroke, you lose cells in your brain and you try to move the affected limb, it doesn’t work, so you learn it doesn’t work. You stop using it and you use your good limb. Taub had the ingenuity to put the good limb in a sling or cast so you can’t use it and then incrementally train the affected limb … I spoke with Taub patients who’d had strokes 50 years before, and there were children there who had had cerebral palsy who were using this treatment and recovering their independence.‘3

The therapy can be individual or part of a group. You have to perform a series of exercises, tasks and games with the weak limb. These are repeated frequently and for many hours at a time. The exercises differ but might include walking on a treadmill, placing objects onto shelves, moving from sitting to standing, or balancing and climbing.4

 

 

  • Possible benefits of Constraint-induced Movement Therapy for stroke

    In 2005, the EXCITE (Extremity Constraint-Induced Movement Therapy Evaluation) study tested the effects of CIMT on 222 stroke patients. All of the participants had some problems with hand and wrist movement. The trial lasted for two weeks. The results showed that the group who received CIMT treatment performed much better in the tests than the control group who did not receive the treatment.5 After two years, The Lancet Neurologyreported on the longer-term impact this trial had on its participants. They found that the 106 patients they re-examined had maintained the progress they had made and had even grown in strength. The researchers found:

    ‘Stroke Impact Scale scores also improved, with significant gains in strength, physical function, activities of daily living, and social participation. This suggests that the “initial gains in hand function and use contribute to secondary changes in functional use of the hand, resulting in increased strength and improved ability in activities of daily living and social participation” …   …the team concludes: “Generally, stroke survivors in this follow-up study achieved a higher quality of life that persisted, which is an ultimate goal of rehabilitation.”’6

    In 2009, another study confirmed that the benefits of CIMT continue for a considerable time after the therapy has ended. Another team of researchers tested 14 participants from their trial four years later. In general, they also concluded:

    ‘There seems to be a long-term benefit of constraint-induced group therapy. Hand function was maintained over time and daily hand use had increased compared to pre-treatment.’7

    There is also evidence to support the claim of CIMT founder Edward Taub that the therapy is effective many years after a stroke. Many of the trials have included participants who suffered a stroke more than a year previously. For example, Taub and his team studied a group of people who had had strokes on average four-and-a-half years prior to the study. His results show that the group who received CIMT improved significantly, while the control group, who did not receive CIMT, showed no improvement.8

  • Arguments against using Constraint-induced Movement Therapy for stroke

    Some researchers have argued that CIMT can be effective when used at the correct time; however, if it is started too early, it could have a negative effect. One study found that rats showed negative physical and behavioural effects when researchers constrained their good limb too soon after injury.This conclusion is supported by another study on rats that compared the effects of restricting the good limb for the first seven days after injury with restricting it for the second seven days after injury. Researchers found that forcing the rat to use its injured limb had a negative effect in both periods. They explain:

    ‘…during the first 7 days after the initial damage [doing so] caused expansion of neural injury and greatly interfered with restoration of function. In contrast, forced overuse of the impaired forelimb during the second 7 days had no significant effect on lesion size but nevertheless interfered with restoration of function. Thus, surviving neural tissue in the damaged hemisphere and recovery of function appear to be vulnerable to prolonged forced overuse of the impaired forelimb throughout the first 15 days, but tissue loss was detectable only when the animal was forced to use the impaired forelimb during the first 7 days after injury.’10

  • Notes and references
    1. ‘Remodeling the Brain: Plastic Structural Brain Changes Produced by Different Motor Therapies After Stroke’ by Lynne V. Gauthier, Edward Taub, et al. In Stroke, 2008;39:1520
    2. Norman Doidge, The Brain That Changes Itself: Stories of Personal Triumph from the Frontiers of Brain Science (James H. Silberman Books) (2007), Chapter 5
    3. ‘Kerry O’Brien speaks with Norman Doidge, author of The Brain That Changes Itself.’ Australian Broadcasting Corporation: Broadcast: 09/09/2008, The 7.30 Report – ABC
    4.  ‘Constraint-Induced Movement Therapy: A New Family of Techniques with Broad Application to Physical Rehabilitation – A Clinical Review’ by Edward Taub, Gitendra Uswatte and Rama Pidikiti. In Journal of Rehabilitation Research and Development, Vol. 36 No. 3, July 1999.
    5. ‘Improving Arm Mobility and Use after Stroke’ Clinical Trial. In www.clinicaltrials.gov. Identifier: NCT00057018
    6. ‘Retention of upper limb function in stroke survivors who have received constraint-induced movement therapy: the EXCITE randomised trial’ by Wolf SL, Winstein CJ et al. In Lancet Neurol 2008; 7:33-40
    7. ‘What is the long-term benefit of constraint-induced movement therapy? A four-year follow-up’ by Brogårdh C, Flansbjer UB, Lexell. In J.Clin Rehabil. 2009 May;23(5):418-23. Epub 2009 Apr 6
    8. ‘A Placebo-Controlled Trial of Constraint-Induced Movement Therapy for Upper Extremity After Stroke’ by Edward Taub, Gitendra Uswatte, et al. In Stroke. 2006(37): 1045-1049
    9. ‘Use-Dependent Exaggeration of Neuronal Injury after Unilateral Sensorimotor Cortex Lesions’ by D.A. Kozlowski, D.C. James, and T. Schallert. In Journal of Neuroscience Volume 16, Number 15, Issue of August 1, 1996 pp. 4776-4786
    10. ‘Use-dependent exacerbation of brain damage occurs during an early post-lesion vulnerable period’ by Humm JL, Kozlowski DA, In Brain Research, 1998 Feb 9;783(2):286-92. T. Department of Psychology and Institute for Neuroscience, University of Texas at Austin

Aviva Cohen is the author and CEO of Neuro Hero