Access Keys:
Skip to content (Access Key - 0)
.

Nomenclature

There are many variations of injury that include combinations of fractures and dislocations. When describing an injury the prefix, "trans", is used when describing a fracture. For instance when a fracture passes through the scaphoid and there is a perilunate dislocation one would say, "transscaphoid perilunate dislocation".

  • Lesser arc injuries: refers to a purely ligamentous injury about the lunate.
  • Greater arc injuries: involve fractures of some of the bones surrounding the lunate
.

Pathogenesis

The injury typically propagates from radial to ulnar through the carpus. The injury force typically enters the carpus through the scaphoid (transscaphoid fracture) or through the scapholunate interval followed by the space of Poirier and finally the lunatotriquetral articulation. Variations of this pattern include fractures through the carpal bones surrounding the lunate, as well as trans-radial styloid fractures.

Four stages of progressive instability

:

  1. Disruption of scapholunate articulation or scaphoid fracture
  2. Force continues through the space of Poirier (lunatocapitate articulation)
  3. Disruption of lunotriquetral articulation and separation of the carpus from the lunate (typically dorsally)
  4. The lunate dislocates from the lunate fossa and rotates into the carpal tunnel, hinged on the palmar ligaments ("spilled teacup sign"). The images below demonstrate a trans-radial styloid, trans-scaphoid, Stage IV perilunate dislocation

Image Added Image Added

 

Natural History

Describe the natural history,epidemiology and prognosis

...

  • Closed vs. open reduction
  • Open reduction preferred if swelling is not excessive
Consider carpal tunnel release with some injuries

...

  • Closed reduction and percutaneous pinning may be employed when an acceptable closed reduction can be achieved
  • Perilunate dislocations: Open reduction is the preferred technique technique 
Dorsal approach:
  • scapholunate joint pin fixation and ligament repair
  • scaphocaptiate pin fixation
  • lunotriquetral reduction and pinning
    • ligament typically nonrepairable
  • Volar approach:
    • carpal tunnel release
    • capsular repair
  • Transscaphoid perilunate dislocation
  • ORIF of the scaphoid
  • CRPP of lunotriquetral joint
  • Consider repairing the volar ligaments
  • ...

    References

    ...

     

    Perilunate Injuries

    Versions Compared

    Key

    • This line was added.
    • This line was removed.
    • Formatting was changed.

    ...

    Space of Poirier: Inherently weak area palmarly between the lunate and capitate that lacks substantial ligamentous connections

    Ref
    9682074
    Ref
    7400560
    Ref
    7400560
    Ref
    9682074
    Ref
    9682074
    Ref
    9682074