Non-constrained implant arthroplasty for the distal radioulnar joint.

A variety of surgical techniques are used to treat the arthritic distal radioulnar joint, which is influenced by aetiology and previous procedures. Four types of ulnar head arthroplasty exist: total ulnar head, partial ulnar head, unlinked total distal radioulnar joint, and linked distal radioulnar joint. Although long-term outcome studies are sparse, short-term clinical and biomechanical studies have shown encouraging results, leading to expanded indications. Based on our experience and a literature review, patients are advised that pain is improved but minor pain is common after strenuous activity. Ulnar neck resorption is common, however, implant loosening is rare. Sigmoid notch erosion is concerning, but appears to stabilize and not affect outcome. A partial ulnar head replacement that retains bony architecture and soft tissue restraints may have benefit over a total ulnar head in appropriate patients. If appropriate selection criteria are met, ulnar head replacement typically produces reliable results, with low revision.