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Which bones are found in the human arm and forearm?

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Front and back views of the human skeleton are shown side by side, with labeled bones including the skull, spine, ribs, pelvis, arms, legs, hands, and feet. Insets detail the bones of the foot and hand, highlighting major bone groups and anatomical terms. — human skeleton Front and back views of the human skeleton.

The human arm and forearm consist of three primary long bones.

The Arm

The upper arm contains a single bone known as the humerus. It articulates with the shoulder blade at the top and forms the elbow joint at the bottom by connecting with the bones of the forearm.12

The Forearm

The forearm is composed of two long bones:

Radius: Located on the thumb side of the forearm, this bone is shorter than the ulna. Its disk-shaped head allows it to rotate, enabling the movements of supination and pronation, which turn the palm forward or backward.32
Ulna: Situated on the inner side of the forearm (when the palm faces forward), the ulna is the longer of the two forearm bones. It features a large notch that articulates with the humerus to form a hinge joint at the elbow.42