What exactly is brachial plexus neuropathy?

Pain: It occurs when there is damage to the brachial plexus, an area where a nerve bundle from the spinal cord splits into the individual arm nerves. Damage to the brachial plexus is usually related to direct injury to the nerve, stretching injuries (including birth trauma), pressure from tumors in the area, or damage that results from radiation therapy.

Parsonage-Turner: The plexus can be involved in widespread nerve disorders, such a nutritional deficiency or diabetes, but can be a site of tumor spread such as lung or breast. An autoimmune process, pars-turn, could occur after surgery, infections, or perhaps spontaneous. Trauma might affect the plexus by causing thoracic outlet syndrome, or brachial plexus stretch. Pain, numbs weakness in arm present.