The nerves that supply the skin and muscles of the shoulder, arm, and hand emerge from the spine and form the brachial plexus. This complex collection of nerves is arrayed between the spine and the shoulder joint. Along the way, it is subject to various types of injuries and entrapments.
Among the milder injuries causing pain and weakness is a group of conditions collectively called Thoracic Outlet Syndrome (TOS) — these involve entrapment or irritation of the nerves. More severe trauma can injure the nerves, stretch them severely, or even break or tear them. The most common causes of severe injuries to the brachial plexus are motor vehicle injuries - particularly motorcycle injuries - and severe blows to the shoulder. An entirely different cause affects infants at the moment of their birth as the shoulder becomes caught in the birth canal in a difficult delivery.
When the brachial plexus is injured so severely as to cause a paralysis of the arm, it is important for the physician to try to determine whether the problem will resolve on its own or whether in will require surgery to repair or reconstuct the nerves. Often, MR Neurography can provide definitive information about the precise location and severity of the injury. In general, in the case of complete paralysis requiring surgical nerve repair, the surgery should be undertaken within six months of the date of the injury.
Brachial Plexus Syndrome Information