Parsonage-Turner syndrome and a localised swelling around the extensor tendons of the hand: a clinical sign indicating increased risk of rupture of the tendon.

Two patients presented with intense pain in the shoulder followed by weakness and paralysis of muscles in the shoulder and arm, together with a peculiar swelling on the hand. The swelling seems to predispose to rupture of the extensor tendon. If this tumour is a regular finding in Parsonage-Turner syndrome, it may also help in making a definitive diagnosis.