I’m getting nervous…

Four-stage explainer of nerve injury: a healthy myelinated nerve, compression trauma displacing the sheath, signal leaking at the bare patch, and the sheath rebuilding.

Nerve injury and repairA nerve drawn as an insulated cable running from the brain to a muscle, shown across four stages. brain muscle

The nerve is an insulated cable. The core carries the signal from the brain to the muscle, and the fatty sheath around it keeps the signal in.

For explanation only. This shows sheath injury, where the core of the nerve is intact. A nerve whose core is cut heals far more slowly. ©2026 Dr Stuart James Arbuckle, All Rights Reserved.