PhD Fekete - SZIE version - 2.2 - Szent István Egyetem

Results
4.2.2.1. The role of lateral and medial collateral ligaments
As an interesting modelling question, the possible effect of the collateral ligaments has been
considered as a factor, which might alter the sliding-rolling ratio. Their important role is
undisputable regarding the stability of the knee, but their contribution to the local kinematics
(sliding-rolling) is currently unknown. For this reason, three prostheses, with additional
collateral ligaments, were examined whether the included ligaments have significant impact on
the sliding-rolling between the contact surfaces (Figure 4.20).
Among the prostheses, the SZIU, the DePuy and the Biotech TP P/S models were chosen for
further investigation. The SZIU model was considered as being a prototype model while the
DePuy and the Biotech TP P/S models for being widely accepted and applied replacements in
the practice.
Figure 4.20. MSC.ADAMS model with collateral ligaments
The medial- and lateral collateral ligaments were represented with linear springs with stiffness
value of 134 and 114 N/mm and damping constant of 0.15 Ns/mm [Momersteeg et al., 1995].
The contact points were appointed according to the studies of Park et al. [Park et al., 2006] and
König et al. [König et al., 2011].
After setting the additional parameters, the simulations were carried out under the same
circumstances as before. The following results were obtained:
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