What are nerves and what is a nerve injury?

What are nerves and what is a nerve injury?

What are nerves?

Nerves form a network of living cables that spread through the body from the brain and spinal cord like the branches of a tree spreading out from its trunk. They carry electrical signals throughout our body to and from the brain.

Motor nerves allow signals to travel from our brain to our muscles which control our movement.

Sensory nerves allow signals to travel from our skin to our brain. These signals allow us to feel pain, cold, heat and touch.

Any given one of the nerves can be motor, sensory of a combination of both.

Nerves can be injured at any point during their path to from the brain to the muscles or skin.

If a motor nerve is damaged the signals to the muscles that travel through the nerve will be affected. If there is no signal the muscle will not work and movement will be affected. We call this paralysis. The paralysis can be very minor, so minor you don’t even notice! Or very severe – where, for example the whole arm doesn’t work, or anything inbetween.

If a sensory nerve is damaged the sensory information for the skin carried by the injured nerve will be affected. This may cause altered sensation in a patch of skin (numbness or pins and needles).

How do Nerve Injuries happen?

Nerves can be cut, stretched or crushed. The treatment of a nerve injury depends on the type of injury. Sometimes nerves which are crushed or stretched may heal by themselves over time so that the signals can pass through them to the muscle or from the skin.

Sometimes, the healing leaves a large scar within the nerve (a neuroma) which affects acts like a wall stoping electrical the ability of the signals to passing through. It is often not clear how bad the stretch or crush. It is therefore important to monitor the recovery of the nerve over time to help us understand if the scar forming will allow the signals to pass through again.

If a nerve is cut and the two cut ends are not lined up, the healing will cause a scar which signals cannot pass through.

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