Carpal Instability: II. Imaging

Abstract

Beyond clinical examination, the various forms of carpal instability are assessed with radiologic methods and arthroscopy. For this purpose, the imaging demand for spatial and contrast resolution is particularly high because of the small ligamentous structures involved. The entities of carpal instability are classified into degrees of severity. Early (dynamic) forms of instability can either be indirectly detected with X-ray stress views and cineradiography or by direct visualization of ruptured ligaments in high-resolution magnetic resonance (MR) imaging and MR or computed tomography (CT) arthrography, with the latter the standard of reference in imaging. Advanced (static) forms of carpal instability are sufficiently well detected on radiographs; visualization of early carpal osteoarthritis is superior on CT. To prevent disability of the hand, the radiologist has to provide an early and precise diagnosis. This case-based review highlights the imaging procedures suitable for detection and classification of carpal instability.

Wrist Trauma: More Than Bones

“…The stability of the wrist is mainly ensured by the integrity of the carpal bones and joint surfaces and by intact intra-articular (particularly the scapholunate interosseous ligament) and intracapsular ligaments. The severity of joint instability depends on the extent of the underlying ligamentous and/or osseous injury [31,32]. Injuries to the carpal ligaments often lead either to functional impairment of the wrist (dynamic instability) or to malalignment of the carpal bones (static instability).…”