Erb’s Palsy is different than other forms of palsy like athetoid cerebral palsy and is characterized by weakness or paralysis of the arm. The disorder causes varying amounts of impairment. The levels of impairment are known by some of the other names for the condition. When the upper arm is the only part of the limb affected, the condition is simply called a brachial plexus injury.
The condition is designated Erb’s paralysis when it affects moving the upper arm and rotating the lower arm. If the condition affects the hand it is called Klumpke paralysis; this form of the condition can cause the eyelid to droop on the side opposite to the affected hand.