Patellar dysplasia means an abnormally-shaped patella.

Page updated October 2023 by Dr Sheila Strover (Clinical Editor)

Wiberg Type 1 patella

Wiberg Type 1 patella

Wiberg Type 2 patella

Wiberg Type 2 patellar dysplasia

Wiberg Type 3 patella

Wiberg Type 3 patellar dysplasia

wiberg type 4 patellar dysplasia

Wiberg Type 4 patellar dysplasia


What is the cause of patellar dysplasia?

Paatellar dysplasia is generally considered a genetic condition, but other possible causes may exist.

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What symptoms can result from patellar dysplasia?

Paatellar dysplasia may lead to subluxation or dislocation of the patella.

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Classification of Patellar Dysplasia

The Wiberg classification of the shape of the patella, based upon the relative lengths of the facets, is widely used to describe different patellar shapes.

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Patellofemoral Dysplasia

Patellofemoral dysplasia is when the groove of the trochlea mirrors any abnormality in the shape of the patella.

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Peer-reviewed papers

  • Quote:

    " a major predisposing factor for instability of the patellofemoral joint....[but] represents an extremely challenging condition to manage."

    Citation: Zaffagnini S, Grassi A, Zocco G, Rosa MA, Signorelli C, Marcheggiani Muccioli GM. The patellofemoral joint: from dysplasia to dislocation. EFORT Open Rev. 2017 May 11;2(5):204-214. doi: 10.1302/2058-5241.2.160081. PMID: 28630757; PMCID: PMC5467684.

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dysplastic patella
kneecap dysplasia
dysplastic kneecap

Dr Sheila Strover (Editor)
BSc (Hons), MB BCh, MBA

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