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jws-mds.20809.mpg12242K Segment 1. Attempted movement of the elbow without proprioceptive facilitation. Despite strong encouragement of the examiner, the patient fails to voluntary move his arm. Note the absence of any discernable muscle contractions in the surface EMG. Segment 2. Force development of the triceps brachii with proprioceptive facilitation. The examiner produces proprioceptive facilitation by passive flexion-extension movements of the elbow. Thereafter, the patient is able to stretch his arm against the examiner's resistance. Note the strong surface EMG signals for the triceps brachii muscle. This video presentation has been abbreviated. The full version will appear on theMovementDisorders DVD Supplement, which is issued bi-annually.

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