Ulnar Head Prosthesis is the perfect tool for treating distal radionulnar joint (DRUJ) disorders. These disorders are commonly associated with painful limitation to forearm rotation which leads to loss of force and instability. Arthrotic changes of the DRUJ are usually treated with the Sauve-Kapandji procedure. This, however, can lead to instability of the ulnar stump, causing a painful radioulnar impingement. In addition to the well-known Ulnar Head Prothesis, the spherical UHP is specifically designed for revising failed Sauve-Kapandji procedures by extending the product range.