Madelung's deformity

Madelung's deformity is an arm condition that results in a deformed wrist.

• Due to abnormal growth, the end of a child’s radius (the bone that connects the elbow to the forearm) grows in the direction of his palm and thumb.
• Because the other bone of the forearm — the ulna — is not affected and continues to grow, the end of the ulna becomes quite prominent on the back of his wrist.