This 45-year old patient presented with numbness and weakness in her right upper limb with signs of mild weakness and wasting of the forearm and hand intrinsic muscles and decreased pinprick sensation over the limb extending to the thorax, anteriorly and posteriorly (C6 to T2). The reflexes in the upper limb were diminished; vibration sense was normal. Examination also revealed hyperreflexia in the lower limb accompanied by mildly increased tone bilaterally with preserved sensory functions. Cranial nerve and cognitive functions were normal.

Is the problem neurological ?

The problem appears to involve the nervous system, since sensory and motor findings were evident with abnormal limb reflexes. Functional inquiry regarding other systems was unremarkable.

Where is the lesion in the nervous system ?

This question is best answered by working from the output (muscle) to the input (CNS) and considering the correlative factors for each anatomical entity which make it more or less likely to be involved in the pathophysiological process:

Based on this analysis, the most likely site is the segmental involvement of the lower cervical spinal cord, given a sensory deficit which follows a dermatomal distribution (C6-T2), and localized motor weakness of the right upper limb. The lower limb signs are consistent with involvement of the descending tracts.


This case represents a chronic condition with progressive features. The most likely scenario is worsening of a long standing condition as opposed to a de novo etiology.