Humerus

A long bone in the upper arm that connects the shoulder to the elbow.

The humerus is the largest bone in the upper limb and plays a crucial role in the structure and function of the arm. It extends from the shoulder joint to the elbow joint, providing leverage for movement and supporting the arm. The humerus consists of several distinct regions, including the head, neck, and shaft, which facilitate the attachment of muscles and ligaments, enabling a wide range of motions.

Terminologia Anatomica

humerus

System

Skeletal system

Function

The primary function of the humerus is to support the movement of the arm and facilitate upper limb mobility. It acts as a lever for various muscles, notably the deltoid and biceps, allowing for actions such as lifting, throwing, and pushing. The bone's proximal end, which forms the ball-and-socket joint with the scapula (shoulder blade), enables a wide range of motion in multiple directions. Additionally, the humerus serves as an attachment point for several muscles that are vital for locomotion and manipulation of objects. Its distal end articulates with the bones of the forearm at the elbow joint, providing stability and strength during forearm movements.

Location

The humerus is located in the upper arm, extending from the shoulder to the elbow. Specifically, it articulates superiorly at the shoulder with the scapula and inferiorly at the elbow with the radius and ulna. The bone is situated adjacent to important structures such as the scapula, clavicle, and the muscles of the shoulder and forearm, allowing for synergistic movement and coordination. Its length and structure play a significant role in the biomechanics of the upper limb, influencing mobility and the capacity to perform tasks requiring upper limb dexterity.

Did You Know?

The humerus has a unique shape that resembles a long rod with various protrusions and indentations for muscle attachment.
In adults, the humerus is approximately 30 centimeters long, but its length can vary significantly among individuals.
A common injury associated with the humerus is a fracture, often resulting from falls or direct trauma to the arm.
The humerus contains a hollow cavity called the medullary cavity, which is filled with bone marrow responsible for blood cell production.