Useless fact
What is the funny bone?
The 'funny bone' is not actually a bone, but rather the ulnar nerve, which runs close to the humerus bone at the elbow.
The term funny bone is a well-known anatomical pun. It refers not to a skeletal structure, but to the ulnar nerve, one of the three main nerves in the arm. This nerve travels from the spine down to the fingers, running remarkably close to the surface of the skin as it passes the elbow joint. Specifically, it lies in a narrow space called the cubital tunnel, resting directly against the humerus bone. Because this area lacks protective muscle or fat cushioning, a sudden impact compresses the nerve directly against the bone. This temporary compression disrupts the nerve's electrical signals, resulting in a sudden, sharp, tingling sensation or numbness that radiates down to the ring and pinky fingers. The English nickname likely originated as a play on words, punning on the anatomical name of the upper arm bone, the humerus, which sounds identical to the word humorous.
Why this is true — The ulnar nerve is the anatomical structure responsible for the sensation known as hitting the funny bone.
Sources
- Why Does Hitting Your Funny Bone Hurt? The Nemours Foundation