There are three bones that form the elbow joint.
The Bones of the Elbow Joint
The elbow joint is a complex structure where three bones meet, allowing for a range of motion in the arm. These bones are:
- Humerus: The upper arm bone. The lower end of the humerus forms the upper part of the elbow joint. It also has two bony protrusions at its end, known as the medial and lateral epicondyles, which can be felt on either side of the elbow joint.
- These epicondyles are not part of the joint itself, but are important landmarks for muscle and ligament attachments.
- Ulna: One of the two bones in the forearm, the ulna forms the lower part of the elbow joint. It connects to the humerus at the elbow joint and is found on the pinky finger side of the forearm.
- Radius: The second of the two bones in the forearm, the radius also connects to the humerus at the elbow joint. This bone is found on the thumb side of the forearm.
Summary of Bones in the Elbow
| Bone | Location | Function in Elbow Joint |
|---|---|---|
| Humerus | Upper arm bone | Forms the upper part of the elbow joint. |
| Ulna | Forearm bone | Forms part of the lower elbow joint, on the pinky finger side. |
| Radius | Forearm bone | Forms part of the lower elbow joint, on the thumb side. |
While other bones are near the elbow, these are the three bones that make up the actual elbow joint. The elbow's structure allows for flexion (bending), extension (straightening) and rotation of the forearm.
