Kienbock disease ( an overall View ). Mohamad Othman , MD 4-10 - 2012. Definition & history. - KD ( or lunatomalacia ) is an idioopathic AVN of carpal lunate which may lead to collapse of the bone and arthritis in the advanced stage.
( an overall View )
Mohamad Othman , MD
- KD ( or lunatomalacia ) is an idioopathic AVN of carpal lunate which may lead to collapse of the bone and arthritis in the advanced stage
- first described in 1843 by Peste in cadaver dissections.
- Robert Kienbock ( 1910) , a radiologist, described the x-ray changes associated w KD.
Natural history of KD remains unclear & un-predictable
- unknown ; theories :
Fault plate hypothesis:
Intrinsic ( lunate) & extrinsic factors ----- elastic deformation of trabeculae 2ry to loading ----- fault plates ---- wall off & interfere w capillary bl. Flow ----- AVN
- repetitive microtrauma in the lunate at risk ( predisposed lunate ) ;
- shape of lunate
- trabecular pattern
- cortical load
- lunate vascular anatomy
( Modified Lichtman Classification )
- Complaint may precede XR changes
- Varies according to stage
- Pain. Tenderness ,swelling, clunk w deviation, dec ROM , weak grip
- Plain XR : views….. Measurements…. Staging.
- MRI : earliest diagnosis : uniform low signal in T1
Carpal height ratio
- ulnar impaction synd. ( MRI)
- DRUJ arthritis
- LunateFx , intraoss ganglion, enchondroma.
Objectives: (a) precollapse (b) postcollapse
Controversial ; not completely-unload lunate.
Choice in transient ischemia. After 3 mo, aggressive management as stage II
Stage I, II, or IIIA with Ulnar-Negative Variance :
(1) Lunate unloading by joint-leveling procedures ( RS > UL) or
(2) Lunate revascularization by VBG
Stage I, II, or IIIA with Ulnar-Positive or Ulnar-Neutral Variance :
(1) unloading by Capitate shortening ± capitate-hamate fusion or radius ost.
(2) VBG ( ± STT-pinning)
Stage IIIB :
-intercarpal fusions (STT and SC )
- Proximal row carpectomy ( PRC)
Stage IV :
- Proximal row carpectomy
- wrist fusion-
- Stage II or III w ulna-neutral or positive wrist
- Lateral closing wedge osteotomy: decrease RU-inclination thus shifting press from lunate
- Medial closing osteotomy or lat opening wedge o
- Step- cut osteotomy
CSO + capito-hamate fusion
1,2 ICSRA VBG
4th CA VBG : retrograde flow through 5th CA from dorsal itercarpal arch
Triscaphe (STT) fusion
Total wrist fusion
Core decompression of distal metaphysis of R & U
والسلام عليكم ورحمة الله وبركاته