126 / 460
125
Introduction
The medial patellofemoral complex, consisting
of the medial patellofemoral ligament (MPFL)
and the medial patellotibial ligament, is the
main passive stabilizer of the patellofemoral
joint. Since it has been shown that rupture of
the MPFL is the main pathological consequence
of patellar dislocation [1] and biomechanical
studies have demonstrated that the MPFL is
the main restraint against lateral patellar
displacement, reconstruction of the MPFL has
become a widespread technique for restoration
of patellofemoral stablity. An additional reason
that MPFL reconstruction became as popular is
the fact that distal realignment procedures such
as transfer of the tibial tuberosity or release at
the lateral patellar retinaculum/capsule have
provided inadequate restoration of patello
femoral stability in every patient, frequently
leading to increased mediolateral instability,
increased patellofemoral pressure or arthritic
degeneration.
Therefore, numerous techniques for reconstruc
tion of the medial patellofemoral complex have
been described with promising clinical results
[2]. However, since it is known that a non-
anatomical reconstruction of the MPFL can
lead to non-physiologic patellofemoral loads
and kinematics [3], the goal of a surgical
intervention must be an anatomical reconstruc
tion. Since the femoral insertion of the MPFL
has been evaluated anatomically [3], biomecha
nically [4], and radiologically [5], the
complications of increased patellofemoral
pressure inflexion associatedwith non-anatomic
femoral graft fixation that is too anterior/
proximal [3] can be avoided. Upon careful
observation of the anatomical shape of the
original MPFL, it is apparent that the patellar
insertion is much wider than the femoral one.
Additionally, Amis
et al.
have proven double
bundle structure provides amore stable proximal
and distal ligamentous structure [3]. Respecting
this anatomic condition, a double bundle
reconstruction at the patellar side is reasonable
to restore native ligamentous morphologic and
biomechanical properties; moreover, this
method lessens the patellar rotation during
flexion-extension movement that may occur
during single bundle reconstruction. Under
these conditions, the double bundle
reconstruction, described earlier [6] shows very
satisfying clinical results. As we know from
ACL reconstruction, direct anatomical/aperture
fixation, [7] provides the highest time-zero
fixation by avoiding elongation of the graft or
“bungee” effect, resulting in the possibility of
early rehabilitation with full range of motion. In
a similar manner, these concepts may be applied
to MPFL reconstruction.
Anatomical double bundle
mpfl reconstruction
P.B. Schoettle