Scapholunate dislocation

or carpal ligamentous injury stage I

– widening of scapholunate joint > 3 mm on the PA view (the “Terry Thomas” or “Madonna” sign)

– it can associated with rotatory subluxation of the scaphoid – “the signet ring sign” (the distal pole is viewed end-on)

If the routine Xray views are normal but the diagnosis is suspected clinically, stress views should be obtained (clenched fist + ulnar deviation).

ED management is a radial gutter splint or a short arm volar + dorsal POP split on the ulnar side, with the wrist in mild volar flexion and radial deviation. They need urgent (same day) Orthopaedics referral for reduction / repair as they are associated with degenerative arthritis and chronic pain.