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Preoperative Planning. What I do Before a UKA
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The Patello-Femoral Compartment
By definition, implanting a unicondylar knee
prosthesis does nothing for a badly worn patello-
femoral joint (PFJ) articulation, and an implant
in this situation will likely lead to failure [5].
Symptoms such as anterior knee pain after
periods of immobility or on descending stairs
are useful to distinguish the source of discomfort,
but the link between symptoms and radiographic
destruction of the PFJ has been questioned by
some authors [4]. In reality, identifying the
Fig. 3: Varus and valgus stress x-rays showing the absence
of lateral laxity and the reducibility of the medial join space.
Fig. 4: Lateral post-traumatic OA. Reducibility of the deformity is shown on varus stress
X-ray (right) and absence of concomitant medial laxity is assessed on valgus stress view (left).