The Caton-Deschamps Index is a measure of the position of the patella relative to the tibia.

caton-deschamps index
It is not always easy to decide the exact points of the lines because the patella is slightly different in shape in each person.


Caton-Deschamps Index and patella alta

The index is of value in determining whether or not there is patella alta (high riding kneeap). It is a ratio of the distance between:

  • the lower point of the part of the patella that makes contact with the femur to the top of the tibial plateau
  • the length of the part of the back of the patella that makes contact with the femur 

The normal range is 0.8-1.2. A ratio higher than 1.3 is suggestive of patella alta.

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

See biography...


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