PhD Fekete - SZIE version - 2.2 - Szent István Egyetem

Literature review
The presented model [Van Eijden et al., 1986] describes a set of non-linear equations
(nine equations), which was solved by Newton-Raphson iteration process [Newton, 1711,
Raphson, 1690]. The model can be applied primarily for static situations, and the transmission
of the forces is realized by the followings: a force F q exerted by the quadriceps tendon is
counteracted by a force F pt in the patellar tendon. The resultant force of these two forces is the
F pf , the patellofemoral compression force, which is the reaction force between the patella and
the femur.
The most important findings of the authors are the followings:
I. The authors found the relationship of the angle between the patellar tendon axis and the
tibial axis (β) as a function of flexion angle (Figure 2.25).
II.
The authors found the relationship of the angle between the patellar tendon and the
patellar axis (ρ) as a function of flexion angle (Figure 2.26).
III. The authors found the relationship of the angle between the patellar axis and the femoral
axis (ε) as a function of flexion angle (Figure 2.27).
IV. The authors found the relationship of the angle between the quadriceps tendon and the
femoral axis (ψ) as a function of flexion angle (Figure 2.28).
V. The authors found the relationship of the angle between the quadriceps tendon and the
patellar axis (ξ) as a function of flexion angle (Figure 2.29).
VI. The authors provided the F pt /F q and F pf /F q ratios as a function of flexion angle
(Figure 2.30 and Figure 2.31).
The above-mentioned angles are represented on Figure 2.24.
Figure 2.24. Anatomical angles
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