Table 1. Etiology-based classification of DRUJ instability.

Etiology	Cause of DRUJ instability
Traumatic	Osseous instability   Extra-articular fracture   Essex-Lopresti fracture dislocation   Galeazzi fracture dislocation   Distal radius fracture  Intra-articular fracture   Ulnar head fracture   Sigmoid notch fracture   Foveal avulsion fracture Ligamentous instability  Radioulnar ligament tear
Inflammatory	Rheumatoid arthritis
Congenital	Madelung deformity
Neoplastic	Multiple osteochondromatosis

Abbreviation: DRUJ, distal radioulnar joint.