Humerus

The humerus is the bone of the upper arm. The smooth, dome-shaped head of the bone lies at an angle to the shaft and fits into a shallow socket of the scapula (shoulder blade) to form the shoulder joint. Below the head, the bone narrows to form a cylindrical shaft. It flattens and widens at the lower end and, at its base, it joins with the bones of the lower arm (the ulna and radius) to make up the elbow. Some people say the "funny bone" is named because it is next to the humerus. It really isn't a bone at all, but is the ulnar nerve, which passes under a prominence of the humerus, where it is vulnerable. To find the funny bone, put the point of the right elbow on a table. Above and to the left of the point is a big knob. When it is struck, the blow pushes the nerve against this knob, causing temporary paralysis. It is no laughing matter, but it is a "funny" feeling.