Instability of the Distal Radioulnar Joint

Instability of the distal radioulnar joint (DRUJ) is an often unrecognized complication of distal radius fractures and softtissue injuries that can impair function. Its incidence and prevalence in Germany in 2023 were 23.55 and 30.55 per 100 000 inhabitants, respectively.

This narrative review is based on publications retrieved by a selective search in PubMed and the Cochrane Library (4 of 10 studies were included in the analysis). Current guidelines and expert recommendations were considered as well, and a query on the topic of this review was submitted to the Central Institute for Statutory Health Insurance and to the German Federal Statistical Office.

After clinical examination and specific test procedures (press test, ulna-fovea sign, dorsopalmar stress test and ballottement test), plain films of the wrist are obtained in two strictly orthogonal projections (lateral and dorsopalmar). Thin-slice computed tomography (CT) (radioulnar quotient method) may be performed as well. Magnetic resonance (MR) arthrography displays DRUJ lesions sensitively (100%) and with increasing specificity (80-100%). Arthroscopy is considered the reference standard for the objective demonstration of triangular fibrocartilage complex lesions with regard to DRUJ instability. Depending on the type of injury, anatomical reconstruction of the injured structures may be recommended, e.g., with refixation techniques, ligament replacement grafts, or osteotomies. Fractures of the styloid process of the ulna (PSU) often accompany distal radius fractures and do not always need to be treated by refixation.

Instability of the DRUJ should be recognized and treated specifically to prevent pain and functional impairment. Further studies are needed to provide better scientific evidence for surgical or conservative treatment.