[Lesion of the ramus profundus of the radial nerve (supinator syndrome). Dissociated radial paralysis of the proximal under arm type].

Anatomy and clinical patterns of dissociated distal paralysis of the radial nerve ("supinator syndrome" or paralysis of posterior interosseous nerve) due to trauma, tumors, rheumatic diseases and with spontaneous onset are discussed in the light of the literature and 6 personally observed cases, 5 of them with traumatic lesions. Surgical exploration and intraneural neurolysis resulted in total or partial remission in 5 instances. In our experience surgical exploration should be performed at the earliest moment after spontaneous recovery is no longer to be expected.