Wiberg classification of patella shape

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.


  • Wiberg type 1 or a
    • roughly symmetrical facets
    • concave facets
    • equally sized facets
    • although presumably the ideal shape of the patella, it is in fact rather uncommon, occurring in only 10% of the general population
  • Wiberg type 2 or b
    • slightly smaller size of the medial facet
    • concave aspect of the lateral facet
  • Wiberg type 3 or c
    • markedly smaller size of the medial facet
    • more vertical orientation of the medial facet

Article information

rID: 30354
Synonyms or Alternate Spellings:
  • Patella shape
  • Patella shape (Wiberg classification)
  • Wiberg classification for patellar shape

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Cases and figures

  • Figure 1: Wiberg classification
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  • Case 1: Wiberg type III
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