Differential diagnosis for left sided weakness, upper limb.

Hi.  I have a 12 year old son complaining of weakness of his left fingers, numbness of the hand and differece in hot and cold stimuli.  When i ask him to place his hands on the bathroom tile he said that the right hand feels colder than the left.  We already went to a neurologist and after examination he said that his weakness is from the left elbow to his fingers.  He didn't tell me his working impression or where the lesion could be.  What is the differential diagnosis for this symptoms.  I'm worried that it may be progressive or there wouldn't be any cure.

[Abhijeet Deshmukh, MD]

Hello.

Since his weakness is from the elbow, I suspect the Biceps muscle in the arm is also weak. This muscle flexes the elbow joint. This muscle and some more muscles up to the hand are supplied by cervical nerves coming from the C5 and C6 segments.

The differentials are (there could be more)
1) Cervical disc bulging / protrusion at C5-C6 / C6-C7 level.
2) Nerve compression somewhere near the shoulder area.

Does he have any weakness on the other upper limb?
Can he close his fingers to make a fist? Which is weaker, the index finger or the little finger?

Regards