USMLE Forum Archives - USMLE Step 1 - mdp46
mdp46
babbu5508 - 06-01-11 00:53
A Iesion of which of the following is the most likely cause of this patient's lower extremity weakness?
/ A. Anterior horns of the spinal cord
/ B. Apical portions of the precentral and postcentral gyri bilaterally
/ C. Lateral corticospinal tracts of the spinal cord
/ D. Lateral spinothalamic tracts of the spinal cord
/ E. Posterior columns of the spinal cord
babbu5508 - 06-01-11 00:53
A Iesion of which of the following is the most likely cause of this patient's lower extremity weakness?
/ A. Anterior horns of the spinal cord
/ B. Apical portions of the precentral and postcentral gyri bilaterally
/ C. Lateral corticospinal tracts of the spinal cord
/ D. Lateral spinothalamic tracts of the spinal cord
/ E. Posterior columns of the spinal cord
The correct answer and explanation will be available after you answer.
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#1
Re: mdp46 dinmenace - 06-16-11 10:33 My answer is: c.
Some patients experience paralysis or paresis temporarily or permanently. A syrinx may also cause disruptions in the parasympathetic and sympathetic nervous systems, leading to abnormal body temperature or sweating, bowel control issues, or other problems.
#2
Re: mdp46
babbu5508 - 06-16-11 11:28 The correct answer is C. Extension of a syringomyelia into the lateral funiculus of the cervical spinal cord bilaterally, affecting the lateral corticospinal tracts, would result in a spastic paresis below the lesion, with upper motor neuron signs as described in this patient.
#6
Re: mdp46 babbu5508 - 06-30-11 18:50 Generally, there are two forms of syringomyelia: congenital and acquired. (In addition, one form of the disorder involves a part of the brain called the brainstem. The brainstem controls many of our vital functions, such as respiration and heartbeat. When syrinxes affect the brainstem, the condition is called syringobulbia.)
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