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P. Sillanpää
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more reliable surgical method than MPFL
repair, which typically address only single
injury location. MPFL reconstruction requires
experience in patellofemoral surgery and may
be considered technically more demanding
than repair. Current evidence for MPFL repair
is relatively limited compared to that for MPFL
reconstruction. MPFL repair cannot be
performed without MRI verification of the
injury location and repair is inappropriate if
performed later in cases of chronic patellar
instability [32]. Repair is perhaps best indicated
in acute cases with MRI-verified patellar or
femoral attachment MPFL disruption within a
fewweeks of the additional indication
for surgical repair could be an osteochondral
fragment from the medial patella with
simultaneous patellar attachment MPFL
avulsion (fig. 1).
In conclusion, primary patellar dislocation
leads to MPFL injury. MPFL injuries can occur
in different locations and may be combined
with an osteochondral avulsion fracture of the
medial patellar margin or an impact fracture,
which should be treated with initial fixation of
the fragment. MRI is recommended for
assessment of the MPFL injury and the
exclusion of additional injuries. Current
evidence supports nonoperative management
for primary patellar dislocation in majority of
the cases. Surgery should probably be
considered for MPFL patellar or femoral
attachment disruptions in cases with one or
more dysplastic features, especially if patella is
highly unstable after dislocation. In some cases,
osseous corrections may be needed, but the
majoritywillstabilizewithMPFLreconstruction
alone. Due to the complex nature of patellar
instability, treatment of primary patellar
dislocation is challenging.
Abstract
Primary patellar dislocation results in medial
patellofemoral ligament (MPFL) injury. MPFL
is the major soft tissue stabilizer of the patella
and MPFL injury may lead to recurrent patellar
instability. The variation in location of injury of
the MPFL and the presence of an osteochondral
fracture produces challenges in clinical decision
making between nonoperative and operative
treatment, including the surgical modality, to
repair or reconstruct the MPFL. Current
evidence suggests that not all primary
dislocations should undergo the same treatment.
MPFL reconstruction may theoretically be
more reliable than repair. Femoral attachment
MPFL injury has been reported to be a risk
factor for recurrent patellar instability.
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