The bone of the upper arm. The dome-shaped head of the bone lies at an angle to the shaft and fits into a socket in the scapula to form the shoulder joint. Below its head, the bone narrows to form a cylindrical shaft. It flattens and widens at its lower end, forming a prominence on each side called an epicondyle. At its base, it articulates with the ulna and radius to form the elbow.
The bone of the upper arm. It has a rounded head, which helps to form the shoulder-joint, and at its lower end presents a wide pulley-like surface for union with the radius and ulna. Its epicondyles form the prominences at the sides of the elbow.
n. the bone of the upper arm (see illustration). The head of the humerus articulates with the *scapula at the shoulder joint. At the lower end of the shaft the trochlea articulates with the *ulna and part of the radius. The radius also articulates with a rounded protuberance (the capitulum) close to the trochlea. Depressions (fossae) at the front and back of the humerus accommodate the ulna and radius, respectively, when the arm is flexed or straightened.
The humerus is most commonly fractured at its neck (the upper end of the shaft, below the head), particularly in elderly people. Fractures of the shaft occur in adults of all ages. Fractures of the lower humerus occur most commonly in children.An X-ray can show a fracture of the humerus. A fracture of the bone’s neck usually requires only a sling to immobilize the bone; a fracture of the shaft or lower bone normally needs a plaster cast. Most fractures of the humerus heal in 6–8 weeks.... ’s humerus, fracture of
Health Encyclopedia