ARUP; ISBN: 978-0-9562121-5-3 - CMBBE 2012 - Cardiff University

Figure 1: Views of the Knee model
Figure 2: Representation of the attachments for menisci partially attached (left) and menisci tips
attached (right).
3. Results
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Figure 3 shows colour maps of the following outputs: ACL first principal stress,
femoral cartilage shear stress in the patello-femoral contact, menisci total
displacement measured as the sum of the x-y-z nodal displacements, and femoral total
displacement. The maximum of these values and of the menisci maximum shear strain
are represented in Table 2. From this table, it can be seen that for menisci horns and
tips attachments, there was an increase on the total displacement of the menisci. The
maximum value of 2.21 mm was reached for the case in which only the tips were
attached. A similar effect happened on the average effective stress of the menisci.
This value significantly increased on the regions were there is a change from sliding
to attached interface. Another important effect with the same characteristic happened
for the maximum shear strain, and in this case there is no relation between the sliding
to attachment interfaces sites. The last parameter that suffered a similar effect was the
maximum femoral displacement, reaching their maximum values in the last time step.
This value significantly increased with the degree of meniscal displacement.
However, values of the first principal stress suffered by the ACL decreased when the
meniscal motion was included, not being very different for either case. The only
parameter that did not seem to suffer a clear change on its values related to the
meniscal attachment was the femoral cartilage maximum shear stress. In both partially
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