Lunate excision with dorsal scaphotriquetral tenodesis in Stage 3b Kienbocks disease

A case series

Dr Steve CarterDivision of Hand Surgery

Martin Singer UnitGroote Schuur Hospital

Introduction• Robert Kienbock 1910 Peste 1843 cadaver specimens • Avascular Necrosis Lunate• The Challenge to develop an alternative treatment option

EtiologySummary

No single factor can be isolated. It is a combination of load , either repeated compression or single fracture, vascular risk, mechanical predisposition and unavoidable continous stress on the lunate resulting in progressive collapse , carpal derangement and ultimate arthrosis

StagingLichtman 1988

Stage 1 Normal XR increased bone scan MRI diagnostic

Stage 2 Increased sclerosis Lunate on XR

Stage 3 Lunate collapse A. Normal carpal alignment without fixed scaphoid rotation B. Altered carpal alignment with fixed scaphoid rotation

Stage 4 Lunate collapse with carpal OA

Staging

Current Treatment options Stage 3b

• Conservative • Denervations• Joint levelling procedures - radial shortening - ulna lengthening• Capitate Shortening - Almquist• Graner Procedure • Limited Carpal fusions - STT fusion - Capitate hamate arthrodesis - Scapho Capitate arthrodesis• ? Question marks remain , reliability, reproducibility, complications ,

psuedarthrosis , symptons vs stage

Questions• The problem is AVN but the result is instability• Is the pain from the avascular lunate , the carpal collapse and

instability or a combination of the above? • Does the capitate in fact migrate if the lunate is excised?• Why do we see very few stage 4 SLAC wrists in kienbocks but

frequently see in scapholunate dissociation• How SLAC is a SLAC wrist ,or are we dealing with different

pathologies

Lunate excision for stage3bPros

• Gillespie 88% good to excellent results 24 cases

• Dornan 16 cases good to excellent results

• Kawai JBJS 1988 70 B 18 cases , 12 year follow up good to excellent , minimal degenerative changes

Cons• Stahl 1947 14 patients poor

results• Therkelsen 1949 excsision

worse than leaving in place

LunateScaphoid Triquetrum

Scaphoid Triquetrum

Method• Our series attempt to deal with the avascular lunate and carpal

instability with a single procedure• Based on the anatomy of the dorsal radiocarpal ligament and

intercarpal ligament

Method• Dorsal incision 3rd 4th compartments• Identify dorsal intercarpal and radiocarpal ligaments• Elevate as a flap (trapdoor) leaving the triquetral attachment intact• Cut the scapholunate lig keeping as close to the lunate as possible• Remove the lunate • Suture DIC ligament to SL ligament • Routine Closure Backslab for 10 days then mobillize

Scaphoid

Dorsal intercarpal lig

Demographics

Age Gender History of trauma Previous surgery

29 F No Yes

30 M Yes No

37 F No Yes

21 F Yes Yes

20 F Yes Yes

56 F No No

Demographics• Average age 36 yrs• 5 Females and 1 Male ( 1 patient lost to follow up )• 1 bilateral kienbocks ( 56 yo female )• Average duration symptons 6.6 yrs• 2 patients with Hx of trauma , 3 with no Hx of trauma

ResultsPatient Pre op

flexPreop ext

Post op flex

Post op ext

Pain pre op

Pain post op

1 55 40 20 20 7 5

2 45 10 10 15 7 4

3 30 45 30 30 8 8

4 30 10 30 10 7 5

5 30 40 45 30 8 5

6 30 30 30 30 8 5

Results

0

10

20

30

40

50

60

1 2 3 4 5 6

pre op flexpreop extpost op flexpost op ext

Results

Results

0

1

2

3

4

5

6

7

8

1 2 3 4 5

Pre op painPost op pain

Results

Lunate gap

X

Y

X/Y = 0.5 Carpal height ratio

Results

00.050.1

0.150.2

0.250.3

0.350.4

0.450.5

1 2 3 4 5 6 7

Pre op CHRPost op CHR

Results

0

1

2

3

4

5

6

7

8

1 2 3 4 5 6 7

Pre op LGPost op LG

Conclusion

• Overall decrease in grip strength

• No alteration in scaphoid rotation

• Preliminary results

Conclusion• Viable salvage operation in ( failed ) grade

3b kienbocks• Simple procedure• Reliable pain relief but decreased range of

movement • No statistically significant change in carpal

height ratio• Lunate gap remains the same ie no

capitate migration