Stroke Recovery - Apraxia

Apraxia

A not too uncommon, but less understood result of stroke, as well as metabolic and traumatic insult to the brain, is a condition called apraxia. This condition was initially recognized as: ‘Disorders of the execution of learned movements which cannot be accounted for by either weakness, incoordination, or sensory loss, nor by incomprehension of, or inattention to commands.’1 Several forms of apraxia are recognized³. Limb-kinetic apraxia is the inability to make precise or exact movements with a finger, an arm or a leg. Ideamotor apraxia is the inability to carry out a command from the brain to mimic limb or head movements performed or suggested by others. Conceptual apraxia is similar to ideamotor apraxia, but infers a more profound malfunctioning in which the function of tools or objects is no longer understood. Ideational apraxia is the inability to create a plan for a specific movement. Buccofacial apraxia, or facial-oral apraxia, is the inability to coordinate and carry out facial and lip movements such as whistling, winking, coughing, etc. on command. Constructional apraxia affects the person’s ability to draw or copy simple diagrams, or to construct simple figures. Oculomotor apraxia is a condition in which the patient finds it difficult to move his/her eyes. Many believe that the most common form of apraxia is ideamotor apraxia, in which a disconnection between the area of the brain containing plans for a movement and the area of the brain that is responsible for executing that movement occurs.²

Whereas with many affects of stroke, where the clinician is able to judge the particular area of the brain that a stroke has injured by certain signs or symptoms, the case is not as clear with apraxia. A common theory as to why this condition results is that the part of the brain that contains information for previously learned skilled motor activities, such as using a spoon to scoop up soup and place it in your mouth, has been either lost or cannot be accessed. The condition is usually due to an insult to the dominant hemisphere of the brain. More often this is located in the frontal lobe of the left hemisphere of the brain. Treatment of acquired apraxia due to stroke usually consists of physical, occupational, and speech therapy. The Copenhagen Stroke Study, which is a large important study published in 2001, showed that out of 618 stroke patients, manual apraxia was found in 7% and oral apraxia was found in 6%.4 Both manual and oral apraxia were related to increasing severity of stroke. Oral apraxia was related with an increase in age at the time of the stroke. There was no difference in incidence among gender. It was also found that the finding of apraxia has no negative influence on ability to function after rehabilitation is completed. The National Institute of Neurological Disorders and Stroke (NINDS) is currently sponsoring a clinical trial to gain an understanding of how the brain operates while carrying out and controlling voluntary motor movements in normal subjects. Their objective is to try to determine what goes wrong with these processes in the course of acquired apraxia due to stroke or brain injury.4