What characteristic symptom is typically associated with Erb's Palsy?

Erb's palsy, also known as Erb-Duchenne palsy, is characterized by weakness or paralysis of the arm due to injury to the upper trunk of the brachial plexus (specifically C5 and C6 nerve roots). The typical symptom associated with this condition is the "waiter's tip" posture.

In this posture, the affected arm hangs by the side and is internally rotated, with the palm facing backwards or outwards. This occurs because the muscles that allow for external rotation and abduction of the arm (which are primarily innervated by the affected nerve roots) are not functioning properly. As a result, the arm appears to be in a position as if the individual is extending their hand to ask for a tip, hence the name "waiter's tip."

The other symptoms listed, such as claw hand, foot drop, and weak grip, are associated with other nerve injuries or conditions. Claw hand typically indicates ulnar or median nerve involvement, foot drop is related to peroneal nerve damage, and weak grip can be indicative of various neuromuscular conditions but does not specifically point towards Erb's palsy. The "waiter's tip" symptom distinctly identifies the neurological compromise resulting from