Klumpke paralysis

Klumpke's paralysis is a partial palsy of the lower roots of the brachial plexus, the bundle of spinal nerves that runs from the back of the neck through the armpit to the arm, specifically involving injury to the C8 and T1 nerve roots. It is named after Augusta Dejerine-Klumpke, who first described it in 1885. It most often follows birth trauma from traction on an abducted arm during delivery, though it can also result from later injuries such as motorcycle accidents, and the right arm is affected more often than the left. Symptoms range from mild to severe and include arm and hand muscle wasting, a clawed hand from paralysis of the small hand muscles, and numbness across the C8 and T1 skin area; when the T1 root is involved it can also produce Horner's syndrome, with a constricted pupil and drooping eyelid. It differs from Erb's palsy, which affects the upper nerve roots C5 and C6 instead. Treatment includes physiotherapy, occupational therapy, electrical nerve stimulation, and splinting or casting.