<unk>  is a dislocation of a bone in the elbow called the radius. Dislocation means the bone slips out of its normal position at the elbow joint.
The injury is also called radial head dislocation.
Nursemaid's elbow
Golfer's elbow
Freckle
Boutonniere deformity
Ulnar bone fracture
Haglund deformity
Tillaux fracture
Bunion