Medically reviewed by Jennifer Steinhoff, MD The humerus is your upper arm bone. It is the longest bone in the upper part of ...

Proper motor function depends on an intact nerve complex to conduct impulses between the central and peripheral nervous systems. Neurons, consisting of are incapable of undergoing mitosis after birth.

About one in 1,000 children are born with brachial plexus birth injury (BPBI), upper extremity weakness or paralysis resulting from trauma to the brachial plexus nerves during childbirth.