The Hip: Preservation, Replacement and Revision Tracking Pixel
Duke Orthopaedics
presents
Wheeless' Textbook of Orthopaedics

Lunate       


  - Acute Ligament Tear - Repair Technique
  - Blood Supply to the Wrist
  - Carpal Instability
  - Differential Diagnosis
  - Kienbock's disease
  - Luno-Triquetral Coalition
  - Perilunate Dislocations
  - Scapholunate Instability
  - Vascularity of the Lunate
  - X-ray findings

- Discussion:
    - lunate articulates proximally w/ radius and distally w/ capitate;
    - it has large volar surface, & is displaced volarward w/ forced dorsiflexion of the wrist;
    - most frequently dislocated carpal bone;
    - w/ flexion capitate slides out from under lunate to create fullness where the capitate depression has been;

- Radiographs:
    - lunate, capitate, and the base of the 3rd metacarpal are in line w/each other & is covered by base of ECRB;
    - colinear alignment of: radius, lunate, capitate, & 3rd metacarpal;
    - deviation of more than 15 deg either way between the links of chain may be viewed as lax, diseased, or damaged;

- Exam:
    - it is palpable just distal to radial tubercle;
    - w/ flexion and extension lunate/capitate articulation may be felt;
    - tenderness of dorsal lunate may suggest Keinbock's dz, while more ulnar tenderness suggests tears of TFC or lunotriquetral ligament;
    - knowing position of ECU & ulnar styloid helds to differentiate ECU tendinitis from distal radioulnar problems


Limited open reduction of the lunate facet in comminuted intra-articular fractures of the distal radius.

Difficult wrist fractures. Perilunate fracture-dislocations of the wrist.

Late treatment of a dorsal transscaphoid, transtriquetral perilunate wrist dislocation with avascular changes of the lunate.



Original Text by Clifford R. Wheeless, III, MD.

Last updated by Data Trace Staff on Tuesday, November 27, 2012 12:20 pm