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Ceramic-on-Ceramic
What is Ceramic-Ceramic
Technology?
The use of alumina ceramic in total hip replacement has a
long and successful clinical history. By taking a ceramic
femoral head and articulating it against a ceramic acetabular
component you can minimize particle debris which can cause
early implant failure. The alumina oxide material provides
high strength and wear resistance and has been shown to last
longer than traditional metal and plastic components. The
manufacturing of these products has evolved into a state of
the art process that ensures a high quality component every
time. Today 100% of all products are inspected before leaving
the plant for evaluating a proper fit and function.
What are the technology improvements
that are available to me today?
Implant technology has improved the wear rate of implants.
In other words, testing indicates that with new technologies
such as ceramic-on-ceramic surfaces, hip implants wear better.
Traditionally, implants were made to articulate with a metal
femoral head and polyethylene (plastic) acetabulum. We know
that polyethylene is a soft material that inevitably wears.
Therefore young, active patients with total hip replacements
can see polyethylene wear on x-ray within several years in
some cases. Osteolysis or bone resorption becomes progressive,
necessitating polyethylene liner exchange and bone grafting
at some point or the problem will get even worse. Ceramic-on-ceramic
surfaces may help to eliminate that wear and the conditions
associated with it.
LINEAGE® Ceramic-on-Ceramic
Total Hip Arthroplasty IDE Study
In April 1997, an FDA Investigational Device Exemption (IDE)
study was begun to determine the effectiveness of Wright's
LINEAGE® ceramic-on-ceramic hip system. By November 2003,
nearly 1700 implants were in place, making it the largest
regulated study ever on a total hip replacement device.
Data collected over the last six years shows that the ceramic
implant is more durable and has fewer complications than traditional
metal and polyethylene implants. Because of such outstanding
performance results, the study concludes that the LINEAGE®
system is both safe and effective.
Please find hereafter the complete study regarding Ceramic-on-Ceramic.
Ceramic
Wear Data
WEAR CHARACTERISTICS OF THE LINEAGE® CERAMIC ARTICULATION
SYSTEM
There are many studies that report wear rates for articulating
couplings. There is no single study that tests all available
orthopaedic couplings in the same manner and reports volumetric
wear. From all the articles that do exist, however, it is
possible to approximate annual linear wear rates for several
orthopaedic couplings. This information is shown in | TABLE
1.19, 20, 21, 22, 23, 24 Alumina ceramic on alumina ceramic
clearly has the lowest wear rate of these orthopaedic couplings.
TABLE 1 | Approximate Annual Linear Wear Rates
for Various Orthopaedic couplings
As stated in the introduction, Sedel, et al followed 86 THAs
with alumina on alumina articulation for nine years and reported
a prosthesis life expectancy of 97.8% even with the inclusion
of revision cases. The authors suggest that "an important
contributory factor may well be the small amount and good
tolerance of wear debris".
Huo, et al reported on another group of alumina on alumina
THAs for eight years and stated that there was no occurrence
of osteolysis in the young and active patient group.25
Reports such as these in the scientific literature suggest
that an alumina/alumina articulating couple can produce successful
clinical outcomes in terms of survivorship and potential reduction
in the generation of wear debris.
Published clinical data with ceramic-on-ceramic hip implants
suggest that surface finish, diametral clearance, material
and sphericity/roundness were key factors affecting historical
wear behavior. Wright Medical Technology has conducted extensive
studies in order to optimize these critical design features.
SURFACE FINISH | LINEAGE® ceramic inserts and alumina
ceramic femoral heads are produced by state-of-the-art equipment
to ensure optimal surface finish parameters.
DIAMETRAL CLEARANCE | LINEAGE® ceramic/ceramic
interface articulation has been designed with the optimal
diametral clearance. Critical to the function of the ceramic
articulation is the clearance between the head and cup. If
the clearance is too large, the contact area is polarized
and can lead to high surface stress resulting in increased
wear. If the clearance is too small, the head and liner can
potentially jam putting stresses on the implant that can lead
to early loosening.26 | FIGURES 13 &14.
MATERIAL | Wright Medical Technology uses
alumina oxide ceramic for the LINEAGE® liners and femoral
heads. From a material standpoint, alumina ceramics provide
high strength with low wear debris generation.
SPHERICITY/ROUNDNESS | Wright Medical Technology's manufacturing
processes utilize state of the art equipment to maintain very
tight tolerances to produce the LINEAGE® ceramic liners
and heads with optimal sphericity.
Follow link to Product
Literature on ie. Linage Ceramic study
Ceramic
History
Both cemented and non-cemented fixation in total hip arthroplasty
have found broad clinical acceptance in the orthopaedic community.
The weakest link in hip replacements has shifted from fixation
issues to the wear debris generated by the articulating surfaces.
When polyethylene is used as a bearing surface, polyethylene
debris is generated in the sub-micron particle size range.1
This debris is widely accepted as a cause of osteolysis.2,3
The goal of eliminating poly wear debris has led to renewed
interest in ceramic articulation.
Ceramic-on-ceramic articulation was first attempted in the
1970's and again in the early 1980's, each time resulting
in limited clinical success.4,5 During the same time period,
Sir John Charnley was experiencing good results with his metal
on polyethylene system.6 These two factors, when combined
with the orthopaedic community's focus on new press-fit implants
during the 1980's, caused ceramic-on-ceramic articulation
development to halt.
In 1977, Sedel began using a cemented titanium alloy stem
with a Ceraver Osteal one piece alumina ceramic cup. These
devices are shown in FIGURES 1 & 2. The alumina cup was
press-fit in 40 acetabular sockets, cemented in 44, and placed
line to line in 2. The series demonstrated a prosthesis life-expectancy
of 97.8% at eight years. In an analysis of their failed prosthesis,
the authors concluded that the failures were due to technique
and not materials.7
 
Picture 1 & Picture 2
Picture 1 | Ceraver Osteal Stem
Picture 2 | Ceraver Osteal Cup and Femoral Head that were
sold as a matched pair.
In the United States, the AUTOPHOR™
ceramic prosthesis was introduced in the early 1980's. The
prostheses consisted of a threaded cup and fenestrated stem
design, as shown in FIGURES 3 & 4. Mahoney, et al, implanted
42 of these prostheses from 1982 to 1985. At an average of
51 months, there was a combined rate of failure for both the
cup and stem of 35 per cent. The authors attribute the unsatisfactory
results to inadequate cup performance and a poor quality of
fit between the femoral stem and the femoral canal. In the
end, the authors believed "that the ceramic articulation
performed well and did not contribute to the unsatisfactory
results."5
O'Leary et al had similar findings when using the AUTOPHOR™.
The authors implanted 69 hips and had a 27% revision rate
with an average time to revision of 26.2 months. The conclusions
of the study were that the failure of the prosthesis could
be "attributed to technical and prosthetic design considerations"
and "failure seemed not to be to any factors pertaining
to the ceramic-on-ceramic bearing."8
 
Picture 3 & Picture 4
Picture 3 | The AUTOPHOR™ Cementless
Stem. Symbols A, B, C were designated as zones on the stem
for radiographic analysis.
Picture 4: | An X-ray of an AUTOPHOR™ Cementless Stem
and Threaded Ceramic Cup. Note the large neck on the ceramic
femoral head.
For more information on the Ceramic-on-Ceramic
technology such as brochures, articles, video etc., please
contact Ortotech
directly.
 
References
1. Campbell, P., et al, "Isolation of Predominantly Submicron-sized
UHMWPE Wear Particles from Periprosthetic Tissues", Journal
of Biomedical Materials Research, Vol. 29: 127-313, 1995.
2. Cooper, R., et al,
"Polyethylene Debris-Induced Osteolysis and Loosening
Uncemented Total Hip Arthroplasty", The Journal of Arthroplasty,
Vol. 7: 285-290, 1992.
3. Willert, H., et al,
"Osteolysis in Alloarthroplasty of the Hip. The Role
of Utrahigh Molecular Weight Polyethylene Wear Particles",
Clinical Orthopaedics and Related Research, Vol. 278: 95-107,
1990.
4. Henssge, E., et al,
"Screwed Conical and Cemented Spherical Al2O3 Acetabular
Components: Follow Up, Histology and Autopsy Data", Bioceramics,
Vol. 6: 277-282, 1993.
5. Mahoney, O., et al,
"Unsatisfactory Results with a Ceramic Total Hip Prosthesis",
The Journal of Bone and Joint Surgery, Vol. 72-A: 663-671,
1990.
6. Charnley, J., et al,
"The Nine and Ten Year Results of the Low-Friction Arthroplasty
of the Hip", Clinical Orthopaedics and Related Research,
Vol. 95: 9-25, 1973.
7. Sedel, L., et al, "Alumina-On-Alumina
Hip Replacement", Journal of Bone and Joint Surgery,
Vol. 72-B(4): 658-63, 1990.
8. O'Leary, J., et al,
"Mittelmeier Ceramic Total Hip Arthoplasty", The
Journal of Arthroplasty, Vol. 3: 87-96, 1988.
9. Adler, E., et al, "Stability
of Press Fit Acetabular cups", The Journal of Arthroplasty,
Vol. 7 No3: 295-301, 1992.
10. Bobyn, J. D. et al:
"The Optimum Pore Size for the fixation of Porous-Surfaced
Metal Implants by the Ingrowth of Bone", Clinical Orthopaedics
and Related Research, Vol. 150: 263-270, 1980.
11. Harms, J., et al,
"Tissue Reaction to Ceramic Implant Material", Journal
of Biomedical Materials Research, Vol. 13: 67-87, 1979.
12. Christel, P., et al,
"Biomechanical Compatibility an Design of Ceramic Implants
for Orthopaedic Surgery", Annals of the New York Academy
of Sciences, Vol. 1523: 234-256, 1988.
13. Boehler, M., et al,
"Long-Term Results of Uncemented Alumina Acetabular Implants",
Journal of Bone and Joint Surgery, Vol. 76-B(1): 53-59, 1994.
14. Tradonsky, S. et al,
"A Comparison of the Disassociation Strength of Modular
Acetabular components", Clinical Orthopaedics and Related
Research, Vol. 296: 154-160, 1993.
15. Wright Medical Technology,
Inc. Internal Report.
16. Wright Medical Technology,
Inc. Internal Report.
17. Wright Medical Technology,
Inc. Internal Report.
18. Wright Medical Technology,
Inc. Internal Report.
19. Semlitsch, M., et
al, "New Prospects for a Prolonged Functional Life-Span
of Artificial Hip Joints by Using the Material Combination
Polyethylene/Aluminium Oxide Ceramic/Metal", Journal
of Biomedical Materials Research, Vol. 11: 537-552, 1977.
20. Charnley, J. et al,
Clinical Orthopaedics and Related Research, vol. 112: 170,
1975.
21. Kawauchi, K., et al,
"Total Hip Endoprostheses with Ceramic Head and H. D.
P. Socket. Clinical Wear Rate, Orthopaedic Ceramic Implants",
Proceedings Japanese Society of Orthopaedics. Ceramic Implants,
4: 253-257, 1984.
22. McKellop, H. et al,
"Friction and Wear Properties of Polymer, Metal and Ceramic
Prosthetic Joint Materials", Journal Biomedical Materials
Research, 15: 619-653, 1981.
23. Boutin, P., et al,
"The Use of Dense Alumina-Alumina Ceramic Combination
in Total Hip Replacement", Journal of Biomedical materials
Research, Vol.22: 1203-1232, 1988.
24. Schmalzried, T., et
al, "Long-duration Metal-on-metal Total Hip Arthroplasties
with Low Wear of the Articulating Surfaces", The Journal
of Arthroplasty, 11:322-331, 1996.
25. Huo, M., et al, "Cementless
Total Hip Arthroplasties Using Ceramic-On-Ceramic Articulation
in Young Patients", The Journal of Arthroplasty, Vol.
11(6): 673-678, 1996.
26. Jacobs, M, MD; Schmidt,
MB, PhD; Farrar, R, B Eng; Rogers, L, MS; Bigsby, R, PhD,
Factors that Influence the Wear Performance of Metal-on-Metal
Hip Prostheses, pp 1-2.
27. Jolles, B.M., Zangger,
P., Leyvraz, P.F.: "Factors Predisposing to Dislocation
After Primary Total Hip Arthroplasty." The Journal of
Arthroplasty, 17: 3, 2002.
28. Lachiewicz, P.F.,
Kelley, S.S.: "The Use of Constrained Components in Total
Hip Arthroplasty." Journal of American Academy of Orthopedic
Surgeons, 10: 4, 2002.
29. Woolson, S.T., Rahimtoola,
Z.O.: "Risk Factors for Dislocation During the First
3 Months After Primary Total Hip Replacement." The Journal
of Arthroplasty, 14: 6, 1999.
30. Li, E, Meding J.B.,
Ritter, M.A., Keating E.M., Faris, P.M: "The Natural
History of Posteriorly Dislocated Total Hip Replacement."
The Journal of Arthroplasty 14:8, 1999.
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