A Prospective, Multi-Center, Single-Arm Clinical Trial of the Safety and Effectiveness of the Aptis PRUJ Prosthesis for the Treatment of Patients With Proximal Radial Ulna Joint Disorders.

Inclusion Criteria: * In order to be eligible to participate in this study, subjects must meet all of the following criteria: 1. Patient is skeletally mature and under 85 years of age. 2. Patient has a painful, unstable radial head due to degeneration or post-traumatic disabilities presenting pain, crepitation, and decreased motion at the radiohumeral and/or proximal radioulnar joint and is otherwise 3. Patients willing and able to understand and sign the informed consent. In the opinion of the Investigator, the patient has the understanding and willingness to comply with all study req…