Magnetic resonance imaging of the wrist ligaments.

The advent of small arthroscopes has enabled the hand surgeon to visualize the ligaments of the wrist directly with resultant increased accuracy in diagnosing and treating pathology. Orthopaedists are now demanding a preoperative assessment and this, in turn, has necessitated that radiologists have a comprehensive understanding of wrist anatomy. High resolution MR imaging can identify the wrist ligaments reliably and provide information concerning their integrity. Interpretation is not straightforward; there is considerable anatomic variation, and there are perforations, defects and degenerative tears that can be troublesome in diagnosing injury. However, with experience and attention to anatomic detail, the radiologist can provide useful information regarding structural abnormalities. When injured, the ligaments of the wrist behave as other joint ligaments do. Findings following injury include discontinuity of normal striated bands, incomplete disruption, irregularities and alteration in normal signal. Fluid pooling around a ligament and concomitant bone injury are other clues to injury. The identification of such structural abnormalities may help to explain altered biomechanics and improve the management of patients following wrist injury.