Deborah Hebert BSc(0T), MSc(Kin) PhD candidate, Ontario Institute for Studies in Education, Clinical Educator (OT), Toronto Rehabilitation Institute Clinical Associate, Department of Occupational Therapy, University of Toronto.
Eric Roy PhD, C Psy, Professor, Departments of Kinesiology and Psychology, University of Waterloo, Graduate Department of Rehabilitation Science University of Toronto, Toronto, ON.
When a person with neurological impairment engages in an unusual action such as pouring hot water into a cup with no tea bag and stirring it with a fork, or cutting bread with a knife oriented upside down and sideways, the impairment of limb apraxia should be suspected. Apraxia has been defined as, " a neurological disorder of learned purposive movement skill that is not explained by deficits of elemental motor or sensory systems".1 While motor problems such as abnormal tone and posture, paresis, ataxia and dysmetria can coexist with limb apraxia,2,3 this movement problem is one of conceptual understanding of action and/or production of movement.4 The deficit cannot be explained by intellectual deterioration, lack of cooperation, sensory disturbances, agnosia, disrupted body schema, visuospatial disturbances or aphasia.3,5 There is evidence that aphasia and apraxia commonly co-occur, as they are predominantly found in right-handed clients with left hemisphere lesions; however, they are often clearly dissociated.