Parsonage Turner syndrome is an inflammation of the brachial plexus nerves, likely viral, characterized by acute pain followed by weakness and numbness.

“parsonage Turner syndrome it's a fascinating study in that whole process from the neck down and the other term for it is a brachial neuritis as in brachial plexus neuritis and it's an inflammation of those nerves we think it's probably viral related because there's usually a viral prodrome Associated it doesn't have to be but it's an acute dramatic onset of pain all through here and then some what we call mixed plexopathy some mixed bag of palsy weakness numbness and it can be in multiple different nerves”