What can cause numbness in hands and fingers?

Numbness. Numbness involving hands and fingers can be caused by various conditions, most commonly carpal tunnel syndrome, other causes may include other upper extremity nerve injuries (such as a pinched nerve in the elbow); a pinched nerve in the neck can also cause numbness in hands/fingers. Best to discuss with your md for an exam.
Pinched nerve. You may have compression or pinching of a nerve in your arm or wrist or from your neck but is best to be evaluated by a neurologist first who can determine where the problem is.