A brachial plexus injury is an injury to the brachial plexus — the network of nerves that sends signals from your spine to your shoulder, arm and hand.
A brachial plexus injury occurs when these nerves are stretched, compressed or, in the most serious cases, torn. This can happen when your shoulder is pressed down forcefully while your head is pushed up and away from that shoulder; a direct contact hit also can compress these nerves.
Brachial plexus injuries are common in contact sports such as football, but they can also result from auto or motorcycle accidents or falls. Babies sometimes sustain brachial plexus injuries during birth. Other conditions, such as inflammation or tumors, may affect the brachial plexus.
Minor injuries may get better on their own, but severe brachial plexus injuries require surgical repair.