1. PRESENT STATUS OFPRESENT STATUS OF
UNICONDYLAR KNEEUNICONDYLAR KNEE
ARTHROPLASTYARTHROPLASTY
20072007
ANTHONY S UNGER, MDANTHONY S UNGER, MD
DIRECTOR; GW UNIVERSITY MISDIRECTOR; GW UNIVERSITY MIS
HIP/KNEE SURGERY CENTERHIP/KNEE SURGERY CENTER
WASHINGTON CENTER FOR HIP ANDWASHINGTON CENTER FOR HIP AND
KNEE SURGERYKNEE SURGERY
2. THE REBIRTH OF THETHE REBIRTH OF THE
UNICOMPARTMENTUNICOMPARTMENT
REPLACEMENTREPLACEMENT
6. UNI HISTORY/NEWUNI HISTORY/NEW
⢠CHRISTIANSEN, 9 YR FU 3.6%CHRISTIANSEN, 9 YR FU 3.6%
REVISIONREVISION
⢠SCOTT, 4 YR FU, 3% REVISIONSCOTT, 4 YR FU, 3% REVISION
⢠REPICCI, 8 YR FU, 8% REVISIONREPICCI, 8 YR FU, 8% REVISION
⢠BERGER, 1O YR SURVIVAL=98%BERGER, 1O YR SURVIVAL=98%
⢠ARGENSON,10 YR SURVIVAL=94%ARGENSON,10 YR SURVIVAL=94%
⢠PENNIGTON,<60,10 YR SURVIVAL=92%PENNIGTON,<60,10 YR SURVIVAL=92%
7. HOW DURABLE ARE UNIs??HOW DURABLE ARE UNIs??
⢠JBJS 2007, FURNES ET AL., NORWEGIANJBJS 2007, FURNES ET AL., NORWEGIAN
REGISTRYREGISTRY
⢠2288 UNI VS 3032 TKA2288 UNI VS 3032 TKA
⢠10 YR SURVIVAL 80% FOR UNI VS 92% FOR10 YR SURVIVAL 80% FOR UNI VS 92% FOR
TKATKA
⢠MECHANICAL LOOSENING MOST COMMONMECHANICAL LOOSENING MOST COMMON
FAILURE MODEFAILURE MODE
⢠40% REDUCTION OF RISK OF REVISION AT40% REDUCTION OF RISK OF REVISION AT
HOSPITALS WERE 25 UNIs DONE PER YRHOSPITALS WERE 25 UNIs DONE PER YR
8. UNI INDICATIONSUNI INDICATIONS
⢠SINGLE COMPARTMENT DISEASE(95%SINGLE COMPARTMENT DISEASE(95%
MEDIAL)MEDIAL)
⢠BY XRAY AND HISTORYBY XRAY AND HISTORY
⢠<10 VARUS, VALGUS OR FC<10 VARUS, VALGUS OR FC
⢠ACL DEF IS OKACL DEF IS OK
⢠ANY AGEANY AGE
⢠WT <250WT <250
9. HISTORYâTHE MAGICHISTORYâTHE MAGIC
WORDSWORDS
⢠ââI HAVE PAIN ON THE INSIDE OF MYI HAVE PAIN ON THE INSIDE OF MY
KNEEâKNEEâ
⢠ââSTAIRS AND SQUATTING DO NOTSTAIRS AND SQUATTING DO NOT
MAKE MY KNEE WORSEâMAKE MY KNEE WORSEâ
10. PREOP STUDIESPREOP STUDIES
⢠WT BEARING AP/30 DEGREE PAWT BEARING AP/30 DEGREE PA
⢠SCOPE HELPFUL BUT NOTSCOPE HELPFUL BUT NOT
NECESSARYNECESSARY
⢠CT/MRI/BONE SCAN NOT NECESSARYCT/MRI/BONE SCAN NOT NECESSARY
⢠MERCHANT VIEWMERCHANT VIEW
⢠LATERAL VIEWLATERAL VIEW
11. IMPLANT SELECTIONIMPLANT SELECTION
⢠FIXED BEARING RATHER THANFIXED BEARING RATHER THAN
MOBILEMOBILE
⢠ROUND ON FLAT MORE FORGIVINGROUND ON FLAT MORE FORGIVING
⢠PROVEN TRACK RECORDPROVEN TRACK RECORD
⢠GOOD INSTRUEMENTSGOOD INSTRUEMENTS
13. POLY WEARPOLY WEAR
⢠GREENWALD, WEAR EQUAL TO FIXEDGREENWALD, WEAR EQUAL TO FIXED
BEARING TKABEARING TKA
⢠POLY FAILURE USUALLY DO TOPOLY FAILURE USUALLY DO TO
MALALIGNMENTMALALIGNMENT
⢠MODULAR TRAY OKMODULAR TRAY OK
14. REVISION OF THE UNIREVISION OF THE UNI
⢠EASIER THAN REVISING HTOEASIER THAN REVISING HTO
⢠MAY NEED WEDGES ORMAY NEED WEDGES OR
BLOCKSBLOCKS
⢠REVISE TO TKA NOT ANOTHERREVISE TO TKA NOT ANOTHER
UNIUNI
16. BERGERBERGER
⢠ââLAST AS LONG AS TKA,LAST AS LONG AS TKA,
LIKE THEM IN >80 ANDLIKE THEM IN >80 AND
<60â<60â
⢠ââMY INDICATIONS AREMY INDICATIONS ARE
EXPANDINGâEXPANDINGâ
17. SCOTTSCOTT
⢠ââALTERNATIVE TO HTO INALTERNATIVE TO HTO IN
FEMALES, GOOD CHOICEFEMALES, GOOD CHOICE
IN OCTOGENARIANSâIN OCTOGENARIANSâ
19. BOOTHBOOTH
⢠ââI DO TKA IN 15 MINUTES, 10I DO TKA IN 15 MINUTES, 10
PER DAY WHAT DO I NEEDPER DAY WHAT DO I NEED
THIS HEADACHE FORâTHIS HEADACHE FORâ
20. UNGERUNGER
⢠IDEAL CANDIDATE 50-65IDEAL CANDIDATE 50-65
OR OCTAGENERIANOR OCTAGENERIAN
⢠ââONLY I/20 PATIENTS AONLY I/20 PATIENTS A
GOOD CANDIDATEâGOOD CANDIDATEâ
21. SURGICAL TECHNIQUESURGICAL TECHNIQUE
⢠MIS, NO PATELLA EVERSIONMIS, NO PATELLA EVERSION
⢠23 HR STAY23 HR STAY
⢠NO CORRECTION, UNI IS ANO CORRECTION, UNI IS A
RESURFACING, NOT A PARTIAL TKARESURFACING, NOT A PARTIAL TKA
⢠CUT TIBIA FIRSTCUT TIBIA FIRST
⢠START WITH BIG INCISION, WORKSTART WITH BIG INCISION, WORK
TOWARDS 4 INCH INCISIONTOWARDS 4 INCH INCISION
22. SURGICAL TECHNIQUESURGICAL TECHNIQUE
⢠CUT TIBIAL SLOPE ANATOMICCUT TIBIAL SLOPE ANATOMIC
⢠IF TIGHT IN FLEXION INCREASEIF TIGHT IN FLEXION INCREASE
SLOPE TIBIA CUTSLOPE TIBIA CUT
⢠IF TIGHT IN EXTENSION,CUT 2MMIF TIGHT IN EXTENSION,CUT 2MM
MORE FEMUR AND/OR DECREASEMORE FEMUR AND/OR DECREASE
SLOPE TIBIA CUTSLOPE TIBIA CUT
⢠2MM LAXITY IN FLEX/EXT GAP2MM LAXITY IN FLEX/EXT GAP
⢠WATCH OUT FOR PATELLAWATCH OUT FOR PATELLA
IMPINGEMENTIMPINGEMENT