Brachial Neuritis
Condition of uncertain aetiology
presenting with pain in the distribution of the affected nerves
Most commonly affects C5 and C6 of the brachial plexus
resulting in denervation oedema of the supraspinatus and infraspinatus predominantly
Occasionally MR imaging can demonstrate enlarged nerves with increased signal but imaging findings within the nerves themselves are uncommon.
Generally self-limiting but residual muscle deficits can be evident.
The condition as it affects the shoulder is called Parsonage Turner syndrome