Summary Carpal instability nondissociative (CIND) is defined as instability between carpal rows (either radiocarpal or midcarpal) radiocarpal instability (between radius and proximal row) midcarpal instability (between proximal and distal row) Epidemiology incidence rare < 1 per 100,000 annually Etiology Pathophysiology radiocarpal instability ("inferior arc injury") high-energy injury ulnar translation signifies global rupture of extrinsic ligaments distal radius malunion is the most common cause may be purely ligamentous or have associated ulnar and radial styloid fractures Associated conditions intracarpal injury (scapholunate or lunotriquetral ligament) acute carpal tunnel syndrome compartment syndrome Anatomy Volar extrinsic ligaments radioscaphocapitate (RSC) long radiolunate short radiolunate radioscapholunate Classification Overview table of wrist instability Presentation History usually no history of trauma (midcarpal) high energy trauma (radiocarpal) Symptoms subluxation that may or may not be painful complain of wrist giving way irritating clunking sign "clunk" when wrist is moved ulnarly from flexion to extension with an axial load Physical exam generalized ligamentous laxity Imaging Radiographs recommended views required login to view 1 more bullet optional login to view 1 more bullet findings sudden subluxation of proximal carpal row with active radial or ulnar deviation on cineradiograph ulnar translation login to view 1 more bullet Treatment Nonoperative immobilization +/- splinting indications login to view 2 more bullets Operative immediate open repair, reduction, and pinning indications login to view 1 more bullet outcomes login to view 2 more bullets midcarpal joint fusion indications login to view 2 more bullets outcomes login to view 1 more bullet osteotomy with malunion correction indications login to view 1 more bullet wrist arthrodesis indications login to view 1 more bullet outcomes login to view 2 more bullets Prognosis volar dislocation is more severe than dorsal