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Ceramic-on-Ceramic Total Hip Device History
Currently, the risk for fracture
of the ceramic component is less than 1 in 2000 implantations
during a period of 10 years (1/20000). Initially, there was a
risk of 1 %!
This material was been introduced in 1970. It was first
implanted by Pierre Boutin in France, afterwards by
Mittelmeier in Germany.
The purpose was to reduce the production of wear particles in
order to obtain better results in the young patient. In the
meantime, more than 150.000 ceramic-on-ceramic devices have been
implanted, especially in Europe.
Initially, there were a lot of
problems, caused by fracture of the ceramic or osteolysis around
the ceramic components. However, other studies of large series
were more optimistic. The first implant devices failed, not only
because of the minor quality of the ceramic (oxidized aluminum), but also because of the wrong design and difficult
surgical technique.
The most significant characteristic
of this friction couple is it's bio inert nature. In normal
circumstances (ideal biomechanical circumstances after
implantation), the wear of the ceramic components is minimal.
The biological reaction is minimized and
consist of the presence of fibrous tissue with very little number of
macrophages and giant cells. However, when mechanical conditions of the
components are less ideal (e.g. in case of fracture or displacement of a
component), there will be a more extensive biological reaction caused by
the increasing number of wear particles. Due to improvements in
material properties of the ceramic, better design of the prosthesis
itself and changes in fixation mechanisms of the prosthesis to the bone
(e.g. use of metal backed cups), the former problems with ceramic have
been corrected, so the choice for ceramic-on-ceramic as friction couple
is an excellent choice. Besides, ceramic-on-ceramic is the only friction
couple currently with better survival rates in young patients (<50
years) compared with the elderly. Long term results of Sedel with ceramic-on-ceramic couple, using a cemented
ceramic cup with a smooth anodized cemented titanium stem, indicate a
survival rate of 83 % after 10 years and 70 % after 15 years. The better
results in young patients below the age of 50 with 86 % survival rate
after 15 years, can be explained by the better bone quality in those
patients.
Survival rate of the stem is 97
% after 15 years for both groups. Currently, the risk for
fracture of the ceramic component is less than 1 in 2000
implantations during a period of 10 years (1/20000). Initially,
there was a risk of 1 %!
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