what causes a pinched nerve
Pinched median nerve. A pinched nerve occurs when too much pressure (compression) is applied to a nerve by surrounding tissues. In some cases, this tissue might be bone or cartilage, such as in the case of a herniated spinal disk that compresses a nerve root.his pressure causes inflammation of the nerve and disrupts the nerve's function. If a nerve is pinched for only a short time, there's usually no permanent damage. Once the pressure is relieved, nerve function returns to normal. However, if the pressure continues, chronic pain and permanent nerve damage can occur.