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Anatomy, kinematics an knee prostheses; 3D variations in knee anatomy?
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much less discussion on its validity with respect
to the study of physical characteristics [2, 8, 21,
26]. Our work in a certain way confirms this by
demonstrating the correlation of morphotype
with the geometric shape of knee.
Our study has also confirmed the influence of
gender on the shape of the knee, and therefore
seems to support the theoretical concept of
gender specific implant geometry, at least for
the intermediate sizes [1, 6, 7, 10, 19, 22, 23].
Whether such implants could lead to improved
clinical results, is however another matter and
until today not proven [5, 11, 13]. In view of
this it is interesting to note that our work also
demonstrated that, within gender, indeed
significant variability exists in mediolateral
versus anteroposterior dimensions, which is
explained by the influence of morphotype.
Patients with smaller knees (predominantly
female) demonstrated large variability between
narrow and wide mediolateral dimensions for
any given anteroposterior size, irrespective of
gender. The same was also true for larger knees
(predominantly male). It could therefore make
sense to consider variable mediolateral implant
dimensions to span this divergence in patient’s
morphology, even within the same gender.
Again, it remains to be seen whether such could
lead to a better clinical outcome, but at least we
believe that the scientific basis exists to support
the theoretical rationale of such concept.
Conclusion
In practice the above would suggest the
necessity for a highly individualized implant
shape and surgical strategy. Recent
technological improvements allowing additive
manufacturing, digital printing, and accurate
component placement according to the patients
native pre-diseased status, makes this option
closer to reality for surgeons than ever before.
Again, it remains to be proven that such
individualized approach indeed would lead to
better clinical results, but at least a strong
theoretical basis thereto exists.
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