Understanding Hip Scores

“Canine Hip Dysplasia is the most common heritable orthopaedic problem seen in dogs. It affects virtually all breeds of dogs, but is especially problematic in large and giant breeds. CHD develops into a degenerative condition (osteoarthritis) of the hip joints. Conventionally, CHD is diagnosed radiographically by the presence of degenerative changes and/or subluxation of the hip joints. The role of subluxation is crucial in the development of CHD but is often camouflaged on the most commonly used radiographic projection of the hips. Radiographic evidence of osteoarthritis confirms secondary changes of CHD, characterised by periarticular osteophyte formation (bone spurs), signs of increased subchondral bony opacity and bony remodelling.

The current system used for scoring radiographs for hip dysplasia in Australia is based the system devised and used by the BVA/KC. There are nine criteria to be evaluated. Scores between 0 and 6 are allocated for all criteria, except the caudal acetabular edge, for which the maximum score is 5. Higher scores indicate greater degrees of radiographic abnormality. The scores for the right and left joints are added to give a total hip score”

“This system of scoring radiographs for hip dysplasia has the advantage that the requirement to assess a number of specific anatomical landmarks ensures relatively objective evaluation of each joint. In addition, the wide range of available score points permits small differences between hips to be recorded. It can be assumed with some confidence that any individual hip score of above 10 will be an indication either of gross instability or of clearly established secondary change…. In an ideal world we would only breed with dogs whose hips score less than 10…. Where the individual hip score are dissimilar, we recommend against using a dog with an individual hip score that is greater than half of the breed average score.”

(Source: Understanding Hip Scores, Leanne Fitzsimmons, On-Line Vets, Veterinary Imaging Associates, http://www.online-vets.com/hipscore_2.html)

Understanding the Scores:

Scored out of: 106 (each hip is scored out of a total of 53. The scores of both hips are combined to give the overall score of the dog making the score out of 106)

Number of catagories scored: 9

The categories being scored are:

1. Norberg Angle: A score of 0-6 is given for each hip.

 2. Subluxation: A score of 0-6 is given for each hip.

3. Cranial acetabular edge: A score of 0-6 is given for each hip.

4. Dorsal acetabular edge: A score of 0-6 is given for each hip.

5. Cranial effective acetabular margin: A score of 0-6 is given for each hip.

6. Acetabular fossa: A Score of 0-6 is given for each hip.

7. Caudal acetabular edge: A score of 0-5 is given for each hip.

8. Femoral head and neck exostosis: A score of 0-6 is given for each hip.

9. Femoral head recontouring: A score of 0-6 is given for each hip.


Combined Scores:

A combined score is the total of both of the pups parents combined – making the total score out of 212.

Acceptable Scores:

The NRC(A) has ruled that its members cannot breed two dogs together if their combined score is above 20. As a result any dog with a hip score of above 20 cannot be bred from if the owner is a member of the NRC(A). The ANKC has no limit to the scores of Rottweilers used for breeding – only that they must be scored.

Helpful Tips:

When looking at buying a Rottweiler puppy it is essential that you ask to see the parents’ hip scores. If the owner of the dogs has not scored their dogs or cannot provide evidence that the dogs have been scored then they are either not an ANKC registered breeder or they are not adhering to the ANKC code of conduct and therefore should be reported.

Reading the scores:

Most people cannot read the scores with any real understanding so here are a few helpful tips when looking at them:

  1. The lower the score the better.
  2. Look at the scores of each category for each hip. If there is any score higher than 3 in any one hip in any one category then it is likely that the dog will develop an issue within that category on that hip as it ages.
  3. The first 2 catagories (Norburg Angle and Subluxation) are the categories which give the best indication of potential hip dysplasia or osteoarthritis. Most of the dogs score is likely to be within these 2 categories. The Norburg Angle measures the angle at which the bones sit within the hip joint. The closer to 0 this number is the better the angle is. Subluxation deals with how loose the bone is sitting within the hip joint. The closer to 0 this is the better the fit. Any score above a 3 in any one hip within either of these categories means that the dog is likely to develop issues as it ages.
  4. The Norberg angle and subluxation categories refer to the hip laxity and design. The 7 categories below them generally measure degenerative changes that have already occurred within the hip joint. These changes are indicators of arthritic issues and degenerative changes to the bone structure.
  5. A clean hip that is low scoring in every aspect is a healthy hip and desirable.