Abstract: Purpose: To present a theoretical construct and pilot data from an analytic technique to simultaneously quantifypositive and negative upper motor neuron (UMN) features.Method: Computerised hand dynamometry was used to measure hand contraction-relaxation cycles during a repetitivegrasp and release task. Measurements of force, time, force velocity and 'grip workÃ¯'Â½ were collected on a pilot sample of 5post-stroke subjects and 5 matched controls. Within and between group differences were analysed.Results: Force, time and velocity dependent aspects of hand performance did not differ between the dominant and nondominantupper-limbs of control subjects. In contrast, the post-stroke group generated less grip force over longer cycletimes with their affected limb, consistent with negative UMN features. In controls, 97% of grip work was task specific,with 3% associated with involuntary, non-task grip work. Conversely, the post-stroke group generated high levels ofinvoluntary, non-task grip work (39%), a feature consistent with positive UMN features of muscle overactivity. Forcevelocity and maximal force were lower in the non-affected limbs of the stroke group than matched dominant limbs of thecontrol group, supporting functional Magnetic Resonance Imaging data that the function of non-affected cerebralhemisphere is abnormal following stroke.Conclusions: The computerised dynamometry analysis paradigm was able to simultaneously quantitate aspects of handperformance affected by positive and negative UMN features within an individual and between groups. This approachuses a clinically relevant, functionally based assessment technique that appears to have greater ecological validity andfewer limitations than current measures of spasticity.Keywords: Hand dynamometer, muscle spasticity, assessment, stroke, grip work.
|Number of pages||8|
|Journal||The Open Rehabilitation Journal|
|Publication status||Published - 2010|