Hip Dysplasia and PennHIP

Hip dysplasia is a common inherited orthopaedic disease, particularly affecting large breeds such as Labradors, German Shepherds and Golden Retrievers. Hip dysplasia is caused by abnormal development of the hip joint, which leads to excessive wear and tear. This results in arthritis, or Degenerative Joint Disease (DJD) which is painful and debilitating.

Symptoms of hip dysplasia and DJD include:

Lameness in back legs
Difficulty jumping, rising, or climbing stairs
Stiffness
Changes in gait (swaying or bunny-hopping)
Pain
Decreased activity

Diagnosis involves manipulation of the hip joints (sometimes under anaesthetic or sedation) and x-rays. Arthritis is irreversible; however, it can be managed with medication, supplements, and surgery.

PennHIP is a specialised screening test, which objectively measures your dog’s distraction index (DI) (the looseness of the hips). From the distraction index, we can accurately predict the likelihood that your dog will develop arthritis, how severe it will be, and take preventative measures early to reduce the impact of arthritis on their quality of life. A DI of 0.3 means that the dog is very unlikely to develop arthritis, where as a DI greater than 0.7 means that the dog has severe hip dysplasia.

PennHIP x-rays require special accreditaton. East Malvern Veterinary Clinic is lucky to have Dr. Lydia Dyas who is fully accredited. X-rays as early as 16 weeks of age can accurately predict future changes to the hips. Detection of problems early can allow us to minimise the progression of the disease. If changes to the hips are severe, corrective surgery can be performed.

We strongly recommend PennHIP xrays for all large breed puppies, and dogs who are showing signs of hip pain. The x-rays must be performed under anaesthesia and can be done at the same time as desexing. For more information, see www.pennhip.org

Many breeding dogs will have had hip scores performed when they are about 1-2 years of age. Most breeders use the Extended Hip View (EHV) to score their dog’s hips. The hip scoring scheme (CHEDS) is run by the Australian National Kennel Council. The major disadvantages with this technique are:

The EHV rotates the hip into the socket, masking hip laxity
The EHV score is heavily weighted towards signs of arthritis. Most dogs at 1-2 years of age even with mild-moderate hip dysplasia will not be showing bony remodelling of the joint
The score is a subjective measure from the radiologist and can be biased by the radiographs selected by the breeder or vet to be scored.
Future disease cannot be predicted with the EHV score.

Good CHEDS/EHV results from a puppy’s parents does not mean that a puppy will also have good hip scores.