As a consequence of a brain injury, the hemiparesis may occur and bring you spasticity, muscle weakness, and a persistent deficit in movement coordination. Such incoordination occurs at least in part because the brain part responsible for mediating an action intention and the part in charge of action execution are no longer intact.
Nearly 80% of people who have had a stroke have more or less trouble moving one side. People with hemiparesis may have trouble moving their arms and legs, difficulty walking and may also experience a loss of balance. As a result, doing simple everyday activities could be difficult. Depending on the damaged area of the brain, the most common type is pure motor hemiparesis: Patients with pure motor hemiparesis have face, arm and leg weakness.
Classic treatment consists of physical the occupational therapy as we mentioned several times in our previous editions. Electrical stimulation to the area of the brain as we presented recently also becomes an interesting treating approach. On the other hand, certain treatments can be helpful in relaxing the muscles in people who have spasticity referring to our last year June’s edition.
A quite common and systematic method is called Modified constraint-induced therapy (mCIT) and it has been presented in our last year January’s edition. It is a focused treatment to stroke patients with hemiparetic arms. Three times a week at their therapist for half an hour each time, patients are asked to practice focused exercises using their weak arm. This therapy could last for 10 weeks. Preliminary studies indicate that mCIT substantially improves affected upper limb use and function in stroke patients.
Certainly, repeated exercises could improve motor activity and allow for smooth controlled movement, as the brain will re-establish the neuronal circuit that mediates voluntary movement. However one disadvantage of this approach is that the recovery is dependent on performance of an impaired limb.
Is there any method independent of the behavioural output of a paretic limb? Yes. Today, we will introduce you another new therapy: Mental Practice, sometimes called Motor Imagery. This therapy is based on when people imagine themselves using a certain body part, areas of the brain and muscles can be activated as if the person is actually doing the activity.
Here is the small model to illustrate one way to do it. The model demonstrates that mirror box for simulation of a left limb moving successfully. The right (unaffected) limb moves around in the “workspace”, giving a reflection of the left (paretic) limb moving successfully in space. You will be instructed to “imaging the reflected limb actually is your limb moving”.
Therefore, your observation of the reflected limb provided a direct perceptual cue of the paretic limb is completing a controlled movement. During the first weeks, you might just have to go through with very simple movements, later in subsequent weeks, you may be asked to do some simple object manipulation like holding a pen drawing some geometric shapes, all this while observing your paretic limb in the mirror.
There are no specific risks involved in participating in motor imagery and it is inexpensive. Motor imagery is actually quite easy to do at home, and many people find it a fun and relaxing way of having additional therapy. Ask your rehabilitation therapist to see if he/she can guide you as to
- how many times a week you should do motor imagery exercises,
- what specific activities and movements you should do,
- what activities you should not do,
- how long each motor imagery session should be,
- how to change activities as you improve.
Have a great imagination journey!
Sources:
American Stroke association
Heart and Stroke Foundation of Canada
Archives of Physical Medicine and Rehabilitation
Reuters