Hip Radiographs - Information to the Veterinarian

We also have information specific to cat owners.

PawPeds is an organisation working for better and healthier animal breeding. In January 2000 the Swedish Maine Coon Cat Club started a public register of hip radiographs. This register is since June 2010 administered by PawPeds. The recommendation is that all Maine Coons should be tested for HD before being used in a breeding programme, in order to reduce the frequency of HD in the breed.

As hip dysplasia is not only found in the Maine Coon breed, it might be of interest to know for other breeds that they also have the possibility to join this health programme. All radiographs that is sent in according to the rules of the health programme will be handled and registered independent of breed.

All results in the register are public 60 days after the cat owner has received the result. The results are published per breed on the Health Data Download page and for some breeds the results are also presented in the pedigree database.

PawPeds collaborate with the veterinarian and radiograph expert Elisabeth Ball who evaluates all the hip radiographs on behalf of the health programme. We believe that it is very important that these radiographs are evaluated by one person only, in order to obtain the most consistent assessment possible.

Below you will find information on how the cat should be radiographed, some recommendations, and how to submit the HD form and radiographs to PawPeds.

Note: Cat owners with breeds other than the Maine Coon are also welcome!


  • Please note that the cat must have an identification such as a microchip or a tattoo
    • The ID number written on the HD form must be verified with a chip reader or by checking the tattoo
    • The ID number and pedigree name must be checked against the cat's pedigree or similar identification paper
  • The ID number and the date of the examination must be exposed into the radiographs, not added digitally
    • If there is room for it, it would help if the cat's pedigree name and registration number is visible on the radiograph too
  • It is also very important that PawPeds' HD form is used
    • One part of the HD form is filled in by the cat owner in advance and the second part by the veterinarian
  • The cat owner must have signed the HD form before the radiographs are made
    • With the signature the owner gives us permission to register and publish the results into the public registry
    • We need sufficient submissions to evaluate the correct frequency of HD in the breeds to see the effect of testing on later generations
    • If the owner refused to sign the HD form i advance, the HD form of PawPeds should not be used and the radiographs should not be submitted to PawPeds
  • The images must be digital and saved in DICOM format
    • The images should not be compressed


A mild sedative (injection) is recommended before the radiograph to facilitate the positioning of the cat. The cat should however not be heavily sedated.

The same routines should be used as radiographing a dog’s hips. The pelvis and the knee joints should be seen on the radiographs. The legs should lie parallel and the knee joint should lie in a straight line with the thighbone. The legs should not be rotated inwards or outwards.

Submit the HD Form and Radiographs

  • Check and fill in information about the examination on the HD form and sign it
  • The HD form and the DICOM file/files with the radiographs are uploaded to PawPeds in the HealthWeb: https://health.pawpeds.com/
    • The HD form must be scanned to jpg, png, or pdf
    • The radiographs must be in DICOM format (.dcm) and the images must not be compressed

The first time an upload is made a personal account must be created. This can be anyone at the clinic with that responsibility, it doesn't need to be the veterinarian. Read more about the HealthWeb to get the overall process described.


The Evaluation Grades

The evaluation grades on the scale used are the same ones as for hip radiographing dogs, but due to the fact that the anatomical picture is different for cats the usual "Norberg’s angle" is not used. This means that we do not use the ABCD evaluation scale. Instead we use "normal", "1", "2" and "3" where each hip will be scored separately:

  • Normal (grade 0) - no signs of hip dysplasia and/or degenerative joint disease and the acetabulum covering at least 50% of the femoral head
  • Grade 1 (mild hip dysplasia) - mild signs of hip dysplasia and/or the acetabulum covering less than 50% of the femoral head but no signs of deforming degenerative joint disease
  • Grade 2 (moderate hip dysplasia) - moderate signs of hip dysplasia and/or signs of deforming degenerative joint disease
  • Grade 3 (severe hip dysplasia) - severe signs of hip dysplasia and/or deforming degenerative joint disease


The cat owner pays directly to PawPeds for the assessment of the radiographs, made by PawPeds' evaluator. There is no action expected from the veterinarian.

Access to the Assessment

When PawPeds' evaluator has made the assessment the result will be visible for you in the HealthWeb. Also until that time you can view the status of the HD cases that you have submitted to the evaluator.


If you have any questions, please don't hesitate to contact the contact persons for the health programme! You can also email This email address is being protected from spambots. You need JavaScript enabled to view it..