Neuroscience Analysis of Occupational Performance (OCTH 455)
and
Neuroscience (PTRS 850)
Marcus Answer

This is only one of several possible answers to the practice question I provided.

The Question

Marcus is a welder at an ornamental ironworks business. Lately, Marcus has been having difficulty using his right hand to hold his welding torch; he frequently looses his grip on it, and the weight of the tool often causes him to drop it. This lead to another problem yesterday, when some molten metal from his project dropped onto his left leg while he was fumbling with his torch. Marcus wasn't even aware of that injury until he smelled burning fabric and flesh.

One possible answer

The boldface portions of the question are relevant to this particular answer.
  1. Weakness & clumsiness of right hand suggests a problem with control of motor output.
  2. Weak grip and inability to support weight suggests proprioceptive problems with right hand.
  3. Inability to sense pain in left leg suggests a problem with the right anterolateral system.
  4. Both upper & lower extermities are involved, suggesting a relatively high lesion.

    Diagram:
    These symptoms suggest the problem is either at or above the level of the brachial plexus, on the right side of the spinal cord.
    The dorsal columns, the anterolateral pathways, and the motor output pathways on the right side of the spinal cord must be involved.

    Answer: Marcus has symptoms indicating a hemisection of the right spinal cord in the cervical region (a.k.a. Brown-Sequard syndrome).

    Return to the Practice questions page for this course.
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    Back to the Top | Last Updated:01/09/08