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Lunate Dislocation

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Other Names

  • N/A


  • Uncommon wrist injury secondary to trauma
  • The Lunate is disarticulated and displaced volarly (dorsal dislocation less common) from both the capitate and the radius.
  • The remainder of the carpal bones remain in normal anatomic position in relation to the radius
  • Frequently missed on initial presentation due to subtlety of radiographs


  • Classically a fall on outstretched hand causing wrist hyperextension, ulnar deviation, and intercarpal supination.
  • Sequence of events:
    • Scapholunate disruption
    • Disruption of capitolunate articulation
    • Disruption of lunotriquetral articulation and Lunotriquetral Ligament
    • Failure of dorsal radiocarpal ligament
    • Lunate rotates and dislocates, usually into the carpal tunnel
  • Epidemiology
    • Carpal dislocations account for less than 10% of all wrist injuries

Risk Factors

  • Unknown

Differential Diagnosis

Clinical Features

  • General: Physical Exam Wrist
  • Often pain and swelling over dorsum of the wrist
  • Limited range of motion of the wrist
  • Median nerve distribution may be diminished due to volar displacement of the lunate
  • May have associated radial styloid, scaphoid, capitate, or triquetral avulsions and dislocations



  • Standard Radiographs Wrist
  • Piece of pie sign is the characteristic triangular appearance of the lunate on the PA view caused by volar rotation of the lunate
  • Spilled teacup sign is found on the lateral x-ray due to volar rotation of the lunate


  • Not required to make diagnosis, may be helpful to clarify soft tissue injuries


Mayfield Classification

  • Stage 1: scapholunate dissociation
  • Stage 2: scapholunate dissociation, lunocapitate disruption
  • Stage 3: scapholunate dissociation, lunocapitate disruption, lunotriquetral disruption
  • Stage 4: Lunate dislocated with median nerve compression



  • Most cases requires surgical management for optimal outcomes

Acute Management

  • Emergent Orthopedic consultation for reduction and stabilization with operative management
  • Immediate closed reduction and splinting alone may be utilized though often associated with poor functional outcomes and redislocation
  • Closed reduction technique
    • Finger traps, elbow at 90 degrees of flexion
    • Hand 5-10 lbs traction for 15 minutes
    • Dorsal dislocations are reduced through wrist extension, traction, and flexion of wrist
    • Apply Sugar Tong Splint


  • Generally requires surgical management

Return to Play

  • Patient's should be emergently referred to Orthopedic Surgery for operative management.
  • Patient's should not be cleared for return to play until proper surgical intervention and therapy.


See Also


Created by:
John Kiel on 18 June 2019 23:03:15
Last edited:
13 October 2022 21:47:58