Pinched nerves tend to occur at places where a nerve travels through a ‘tunnel’ of ligaments and bony surfaces, and the wrist (carpal tunnel syndrome, caused by compression of the median nerve) and elbow (cubital tunnel syndrome, caused by compression of the ulnar nerve) are the most common locations for these injuries to occur.
Both carpal and cubital tunnel syndromes may be caused by any of a number of factors that reduce the space inside the tunnels that house the nerves. These include:
- Trauma or injury to the wrist or elbow.
- Over-use of the hands or elbows (for example, participating in work or sporting activities that involve long periods of repetitive movements, such as computer work, assembly line work, construction work, gardening or golfing). In the case of cubital tunnel syndrome, resting the elbow on a hard surface for long periods of time may also contribute.
- Fluid retention (for example, as a consequence of pregnancy).
- Inflammation of the tissues (for example due to rheumatoid arthritis).
Deficiency of vitamin B6 may also be associated with carpal tunnel syndrome.
The sciatic nerve travels from the spinal cord, into the buttock and then down the thigh and leg. Sciatica occurs if a disc between the vertebrae bulges out, causing pressure on the sciatic nerve. This is often referred to as a ‘slipped disc’.
Osteoarthritis may also cause sciatic pain by narrowing the space available for the nerve to travel through. Accordingly, sciatica becomes more prevalent as we get older and the bony and cartilaginous structures of the spine degenerate.