Patellar instability with medial patellofemoral ligament tear

Case contributed by Derek Smith , 23 May 2018
Diagnosis certain
Changed by Brian Gilcrease-Garcia, 23 May 2018

Updates to Study Attributes

Findings was changed:

Small joint effusion.

Pattern of bone bruising (high signal on PD fat sat sequence) in the medial patellar facet and lateral femoral condyle suggests recent lateral dislocation.

A number of features supporting patellar instability: shallow trochlea, borderline TTtibial tuberosity - trochlear groove (TT-TG) distance, and lateral patellar tilt.

Recent lateral dislocation, with bone bruising (high PD fat sat signal) in the medial patellar facet and lateral femoral condyle.

Signal change in the medial patellar retinaculum, with discontinuous/torn medial patellofemoral ligament. Oedema extends along the medial supporting structures, including the MCL.

Normal menisci, ACL, PCL and lateral collateral complex. Normal patellar and included quadriceps tendon.

Updates to Case Attributes

Body was changed:

There are a number of "typical" features for patellar instability/dislocation in this case including a flattened trochlea, malalignment, and bone oedema consistent with recent dislocation. The medial patellofemoral ligament and retinaculum are review areas in MRI knee, and when torn can continue to leave the patella unstable but is. Instability may be initially managed with physiotherapy.

  • -<p>There are a number of "typical" features for patellar instability/dislocation in this case including a flattened trochlea, malalignment, and bone oedema consistent with recent dislocation. The medial patellofemoral ligament and retinaculum are review areas in MRI knee, and when torn can continue to leave the patella unstable but is initially managed with physiotherapy.</p>
  • +<p>There are a number of "typical" features for patellar instability/dislocation in this case including a flattened trochlea, malalignment, and bone oedema consistent with recent dislocation. The medial patellofemoral ligament and retinaculum are review areas in MRI knee, and when torn can continue to leave the patella unstable. Instability may be initially managed with physiotherapy.</p>

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