Trapezius Palsy

Trapezius palsy results from an uncommon nerve condition in the shoulder that can cause pain and weakness. In order for muscles to work properly, the nerves that innervate (supply) them must also function appropriately. If the nerves are somehow damaged or compressed somewhere along their course, it can affect their ability to conduct signals to the muscles. When this occurs, nerve function decreases and the targeted muscle experiences weakness, atrophy (decreased size), and loss of function.