Arm · Long bone
Humerus (Upper Arm Bone)
The humerus is the long bone of the upper arm, running from the shoulder to the elbow. It forms the ball of the shoulder joint and part of the elbow, and anchors the muscles that move the arm.
What it is
The humerus is the single bone between the shoulder and elbow. Its rounded head forms the shoulder's ball-and-socket joint; its lower end forms part of the elbow.
Where it is
The upper arm, from the shoulder joint down to the elbow.
What it does
Connects the shoulder to the forearm, forms the shoulder and elbow joints, and provides attachment for major arm and shoulder muscles.
Connections
Joints and connections
- Shoulder joint (with the scapula)
- Elbow joint (with the radius and ulna)
When things go wrong
Common injuries and conditions
- Humeral fracture (shoulder end common in older adults after a fall)
- Shoulder dislocation involves the humeral head
Education and reference only. This explains the anatomy in plain terms; it is not a diagnosis. A severe injury, a visibly deformed limb, or the inability to move or bear weight needs urgent assessment — call 999 or go to A&E for a serious injury.
Did you know?
An interesting fact
The "funny bone" feeling comes from knocking a nerve that runs behind the lower end of the humerus at the elbow.
Answers
Humerus: frequently asked questions
Where is the humerus?
The humerus is the bone of the upper arm, running from the shoulder to the elbow.
Why is knocking my elbow so painful?
The "funny bone" sensation is caused by hitting the ulnar nerve where it passes behind the lower end of the humerus at the elbow — not by hitting bone itself.
Explore the arm
Related bones
Sources
Where this is drawn from
- NHS — Anatomy and body systems
- Gray's Anatomy for Students (Drake, Vogl, Mitchell)
- TeachMeAnatomy — skeletal system
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