When the outer side of a thigh becomes numb and there are burning, stinging or other painful sensations in the same area, the problem is usually due to a pinched or injured nerve in the pelvis.
Cervical Radiculopathy: Diagnosing a Pinched Nerve in the Neck
A pinched nerve in the cervical spine can be a pain in the neck. It can also cause pain in the shoulder and arm, as well as numbness and weakness.