Clinical aspects of ceramiconceramic articulations

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Clinical aspects of ceramic-on-ceramic
articulations
Dr.-Ing. Thomas Pandorf Director Scientific
Affairs CeramTec AG Department Medical Devices,
Plochingen
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(No Transcript)
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Open questions in hip endoprosthetics
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Pure alumina oxide ceramics
BIOLOXforte Highly purified alumina oxide

• High hardness
• High stiffness
• High chemical durability
• Affinity to polar liquids
• Extremely low wear
• Moderate fracture strength and toughness

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In-vivo wear rate of different hip pairings
Oxinium vs XPe 0,004 - 0,059 (Garvin et al.,
CORR 2008)
Bitsch et al., JBJS 08 Olyslaegers et al., JoA 08
Different authors
mm/y
0,1
0,05
0,005 bis 0,03
0,002 bis 0,005
0,05
0,03
0,02
Me-Pe
Me-XPE
Me-Me
Ce-Ce
Ce-PE
Ce-XPE
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Wear rate of different hip pairings

• Linear Volumetric
• Metal on poly 0.2mm 55.71mm3
• Ceramic/poly 0.1mm 17.10mm3
• Metal/metal 0.01mm 0.88mm3
• Ceramic/ceramic 0.005mm 0.04mm3

Greenwald and Garino, JBJS, 2001

• Different wear rates under ideal conditions
• Metal/metal wear rate up to 200 times higher
  with malaligned components
• Linked with osteolysis
• Only anecdotal reports on osteolysis due to
  ceramic debris

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Clinical results
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Ceramic/PE vs Metal/PE
Ceramic/PE 2 Zichner 1992 Metal/PE 5 bis
10 Ceramic/PE 5,6 Weber 1989
Metal/PE 9,4
comparable HTEP systems
Revision rate 2 to 5 fold less
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Ceramic/PE
Weber (1981) 50 reduced UHMWPE wear Semlitsch
et al. (1989) 38 reduced UHMWPE wear Oonishi et
al. (1989) 50 reduced UHMWPE wear Schuller et
al. (1990) 73 reduced UHMWPE
penetration Zichner et al. (1992) cup
penetration rate in half Bragdon et al.
(1995) no improvement Semlitsch et al.
(1997) 50 reduced UHMWPE wear Böhler et al.
(2000) 2-22 times lower wear
Clinical comparison mostly in agreement
(less wear)
Sauer W.L. et al., In Jacobs J.J., Th. L. Craig
(Eds.), Alternate Bearing Surfaces in Total Joint
Replacement, STP 1346, ASTM, West Conshohocke,
PA, USA, 1998

Böhler et al. JBJS-Br 82, 2000
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Ceramic/PE vs Metal/PE
Examination of 36 retrieved CoCr heads (32 mm), Ø
follow up 9 years, and 56 retrieved alumina heads
(32 mm), Ø follow up 8.5 years
lower surface roughness Ra 0,011 0,003 compared
to CoCr heads (0,032 0,015) lower wear rate
0,13 0,05 mm/year compared to CoCr heads (0,21
mm 0,09 mm)
Lower revision rate with Ce/PE
Kusaba et al., DGOOC 2004
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Ceramic/PE vs Metal/PE
Prospective Study (EBRA)
93 TEP (80 Pat.), cementless
13 Me/PE, 80 Ce/PE, 32 mm
ø 52 years

ø FU 19,3 years
linear wear Ce/PE 0,107 mm/y vs Me/PE 0,190 mm/y


Revision rate Ce/PE 13,8 vs Me/PE 46,2


Metal ball head ? more PE wear ?higher revision
rate

Ihle et al. Orthopädische Praxis 5, 2009
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Ceramic/PE vs Metal/PE
Matched group of patients FU
15 years 226 THR in 215
patients
Gamma irradiated PE
(5 mrads)

Mean linear wear for MoP group 0.102 mm/y
Mean linear wear for CoP group 0.058 mm/y

35 of Me/PE showed more than 0.1 mm/y
Descamps et al. EFORT 2009
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Ceramic/PE Ceramic/Ceramic
Migration behaviour


No differences
Pitto et al. (2003) Schmidt et al.
(2003) Schwämmlein et al. (2002) Ilchmann et
al. (2002) Hendrich et al. (2000) Scheller et
al. (2000)

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Clinical performance
In-vivo wear of Ce-PE vs. Me-Pe Wear and revision
rate with Me double
Zichner et al, Orthopäde 1997
475 Ce-Ce bearings, 10 year follow-up 10-year
Kaplan-Meier survivorship 95.9
Capello et al, J. Arthro. 2008
200 Ce-Ce bearings, 5 year follow-up Survivorship
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Kim et al, AAOS 2009
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Mechanical Resistance, ceramic fracture
Fracture rate 0,02
The fracture rate is extremely low, but it is
too high
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Cause of THR revisions in 2006
n8554 revision surgeries
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Comparison of the microstructure
BIOLOXdelta
BIOLOXforte
Aluminum oxide
Zirkonium oxide
Platelet
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Schema Rissausbreitung
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Fracture strength and toughness
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New material less fracture?
BIOLOXforte 0.021 , or 21 per 100,000 implants
(based on more than 2 million components since
2000) BIOLOXdelta 0.003 , or 3 per 100,000
implants (based on more than 400T components
since 2000)
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Advantageous behaviour under severe conditions
Microseparation
BIOLOX forte
BIOLOX delta
Wear volume after 5 Mio cycles
microseparation (Clarke, BIOLOX Symposium)
Better performance under severe conditions
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The implantation angle is important!
Possible consequences of too much/not enough
inclination/anteversion
Posterior/anterior impingement Subluxation/Edge
loading Large increase of contact stresses Loss
of lubrication film Diligence for all bearing
couples!!!
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The implantation angle is important!
Further influencing factors
Lateralisation/Medialisation of the shell Pelvis
position Stem position/Stem antetorsion
J. Fisher, ISTA 2008
Dandachli et al., CORR 2008, Krebs et al., CORR
2008
Ganapathi et al., CORR 2008
Band laxity may lead to microseparation ?
increased wear due to impact! (Manley et al., JoA
2008, Komistek et al. AAOS 2009, Knahr, EFORT
2009)
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Revision rates
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Open questions in hip endoprosthetics
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Conclusions

• Ceramic bearing couples have proven advantages

5 Million implanted since 30 years
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Conclusions

• Ceramic bearing couples have proven advantages
• Diligence is necessary to minimize risks

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Conclusions

• Ceramic bearing couples have proven advantages
• Diligence is necessary to minimize risks
• BIOLOXdelta provides wider application range

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Conclusions

• Ceramic bearing couples have proven advantages
• Diligence is necessary to minimize risks
• BIOLOXdelta provides wider application range
• Design and material go together!

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Thank you!