2. Kienbock disease
( an overall View )
Mohamad Othman , MD

3. 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
- first described in 1843 by Peste in cadaver dissections.
- Robert Kienbock ( 1910) , a radiologist, described the x-ray changes associated w KD.

4. Epidemiology Natural history of KD remains unclear & un-predictable
15 and 40 years
dominant wrist of men engaged in manual labor
Natural history of KD remains unclear & un-predictable

5. Aetiology : Fault plate hypothesis: - unknown ; theories :
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 ) ;

6. Extrinsic factors: - ulnar variance : capitate - lunate loading
ulnar-negative variant wrist is common association ( Hulten, 1928).
ulnar-positive variant
- load type
- instability

7. Intrinsic factors: - shape of lunate - trabecular pattern
- cortical load
- lunate vascular anatomy

8. Staging
( Modified Lichtman Classification )
Stage I: Radiographically normal lunate or with small fracture lines
Stage II: Sclerosis of lunate
Stage III A: Collapse or fragmentation of lunate
Stage IIIB: Lunate collapse with carpal malalignment ie; proximal migration of capitate (carpal height ratio <0.54 ± 0.03) and fixed hyperflexed rotation of scaphoid( DISI)[radioscaphoid angle > 60]
Stage IV: Generalized wrist arthrosis

9. Stage-I
Stage-II
Stage-III
Stage-IV

10. Clinical picture Investigations
- Complaint may precede XR changes
- Varies according to stage
- Pain. Tenderness ,swelling, clunk w deviation, dec ROM , weak grip
Investigations
- Plain XR : views….. Measurements…. Staging.
- CT
- Scintigraphy
- MRI : earliest diagnosis : uniform low signal in T1

11. XR

12. Stahl index:
Normally;B/A= 50%
Carpal height ratio

13. CT scanning:

14. MRI

15. Differential diagnosis:
- ulnar impaction synd. ( MRI)
- DRUJ arthritis
- Lunate Fx , intraoss ganglion, enchondroma.

16. Treatment Methods: Objectives : (a) precollapse (b) postcollapse
Established methods:
Direct vascularization
Indirect vascularization ( unloading procedures):
joint-levelling procedures
limited carpal fusions
Salvage procedures:
PRC
wrist arthrodesis
Optional & controversial methods:
- conservative
Lunate excision ± replacement ( PL tendon ball , silicon, titanium)
- Core decompression of distal metaphysis of R & U
- Temporary ST pinning ; 3-6 mo . Stage III
- External fixation
- RSO in stage IIIB
- RO + VBG in stage III
- Wrist denervation; stage IV
- Arthroscopic debridement

17. Treatment Algorithm Stage I:
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)

18. Treatment Algorithm ( cont.)
Stage IIIB :
-intercarpal fusions (STT and SC )
- Proximal row carpectomy ( PRC)
-RSO
-Lunate excision
Stage IV :
- conservative
- Proximal row carpectomy
- wrist fusion-

19. Radial shortening osteotomy
Approach ; volar > dorsal
2-3mm ( not > 4mm ; UC impaction )
Meaphyseal / meta-diaphyseal
Not decrease ROM
Not in ulna positive wrist

20. Ulnar lengthening osteotomy
Disadvantages;

21. Distal radius wedge osteotomy
- 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

22. Capitate shortening osteotomy
CSO + capito-hamate fusion

23. VBG Sources: + unloading procedure: - Base of 2nd or 3rd metacarpal
Neck of 2nd meatacarpal
1,2 ICSRA
- 2,3 ICSRA
- 4th or 5th CA
- Hori technique
- Pisiform PQ
+ unloading procedure:
- external fixator or
- temporary STT-pinning or
- radius osteotomy

25. 2,3 ICSRA VBG
1,2 ICSRA VBG

26. 4th CA VBG : retrograde flow through 5th CA from dorsal itercarpal arch

28. Limited carpal fusion
- Objective : redistribute stresses away from lunate
- Correct scaphoid malrotation 1st
- SC / STT
Decreases ROM
Excise lunate; only if fragmented w marked synovitis

29. Temporary STT-pinning
Triscaphe (STT) fusion
SC- fusion

30. Prox raw carpectomy
Total wrist fusion

31. Incisions for wrist denervation
Core decompression of distal metaphysis of R & U

32. والسلام عليكم ورحمة الله وبركاته
وشكرا
THANK YOU
والسلام عليكم ورحمة الله وبركاته