Presentation
Anterior knee pain
Patient Data
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MRI study shows features of Wiberg type 3 or c of the patella in the term of:
- markedly smaller size of the medial facet
- more vertical orientation of the medial facet
Associated medial patellar contusion and corresponding lateral femoral condyle contusion consistent with patellar maltracking / transient lateral patellar dislocation. Medial facet focal chondral ulcer and mild joint effusion are also noted
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Annotated images highlight the findings
Case Discussion
Wiberg classification is a system used to describe the shape of the patella based mainly on the asymmetry between the patellar medial and lateral facets on axial views of the patella. Increasing number type indicates a larger degree of asymmetry.
This case is a good example of Wiberg type 3 or c that is at great risk of dislocation with subsequent patellofemoral instability as demonstrated in this case