Spilled Teacup Sign

Spilled Teacup Sign

A radiologic sign seen in ligamentous instability of the wrist in which a hyperextension injury results in a lunate and perilunate dislocation, causing the scaphoid to extend and strike the dorsal margin of the distal radius. Rupture of both the volar radioscaphoid and the scapholunate ligaments frees the proximal scaphoid, and compressive forces pin the capitate between the scaphoid and lunate. Unchecked dorsiflextion displaces the distal carpal row to a position dorsal to the lunate and radius. On that background, further hyperextension ruptures the dorsal radiocarpal ligament causing volar displacement of the lunate, the concave surface of which corresponds to the ‘teacup.’ Physical exam should assess the median nerve which may be injured or compressed by the 'pile-up' in the wrist. Management requires orthopaedic intervention