Entrapped nerves happen when there is an abnormal pressure placed on a nerve. Injuries or conditions causing inflammation or swelling to the surrounding tissues can create an extra force on the nerve. Consequently, a reduction in blood flow occurs. This can bring about nerve irritation and trigger sensations that are not typical. Even a repeated or extended pushing on a nerve can compress or trap it.
When a body is injured, the inflammatory process is the body's protective and healing mechanism. Characterized by swelling, inflammation can affect the tendons, ligaments, and muscles surrounding the nerves and squeeze them. Conditions such as herniated discs, arthritis, and lesions, such as cysts or tumors where an irregular mass or bulge is present, can impinge or restrict a nerve.
Also referred to as pinched nerves or compression neuropathy, entrapped nerves can cause sensations like a prickling or burning, and pain. It can also bring about a feeling of numbness or weakness. These feelings can travel the length of the nerve, creating a condition called referred or radiating pain. This is when the location of the nerve pressure is not where the actual symptoms are felt. Leg or foot pain, for example, could be set off by having a disc herniation in the lumbar or low back area.
The nerve irritation could be instigated by the person staying in one position for a long amount of time or repetitive movements. Carpal tunnel syndrome is an example where the median nerve in the wrist becomes irritated and pinched. This could be from holding the hand and wrist in a poor position for long periods of time with too much pressure on the nerve. It could also be brought on by consistent recurring hand and wrist movements, causing the area around the nerve to swell.
When the nerve becomes constricted, the flow of blood slows. This sluggish movement of blood can make nerves extremely sensitive to even small amounts of change in pressure. Diabetes restricts blood flow to nerves, which can trigger nerve entrapment symptoms.
Some health conditions cause inflammation which could lead to entrapped nerves. Arthritis and lupus can produce chronic swelling issues. Long-term pressure to nerves can trigger unremitting symptoms and eventually lead to nerve damage. Persistent force on the nerve can also lead to weakness in the muscles around it. Long lasting or recurring entrapped nerves may also cause the muscle to waste away. This is a condition called atrophy.