Neuroscience Analysis of Occupational Performance (OCTH 455)
and
Neuroscience (PTRS 850)
Sensory Review: Question #3
The Question
From a neurological viewpoint, why would tugging on a limb having a spastic muscle be a poor therapeutic choice? What would be a better choice? Explain why, both therapeutically and neurologically, in words appropriate for use with either a 10 year old or a 67 year old client.
The Answer
Muscles contain sensory cells which are sensitive to stretching of the muscle. When these cells are stimulated by stretching, they cause a reflex contraction of the muscle. When you yank on the lower arm of a person with spasticity of the arm muscles, these cells cause the muscles to contract even more than they already may be contracted. Muscles also contain other cells which are sensitive to tension, and a contracted muscle is more tense then a relaxed muscle. These cells protect a contracted muscle from damage due to too much tension by forcing the muscle to relax when these cells are stimulated too much. By pulling firmly but steadily on that same person's arm, we can fool the protective cells into believing the muscle is in danger, and they will make the muscle relax. This will work for any spastic muscle, but the effects are only temporary and the length of time the muscle is relaxed will depend on things like the amount of spasticity, the size of the muscle, and how much or how often the muscle is stretched after it has relaxed.
(simple language isn't always so easy, eh?)
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