Patella Luxation (also known as Luxating Patellas) is a condition where a dog’s kneecap dislocates from the joint in one or both hind legs. Dogs can be affected in one or both hind limbs and the most common sign that a dog is affected is intermittent lameness characterised by a “skipping” gait. Seek veterinary advice if you suspect your English Toy Terrier is affected by Patella Luxation. On this page:
1. Symptoms of Patella Luxation
Symptoms of Patella Luxation usually develop when an English Toy Terrier is still a puppy, before 12 months of age. Whilst it is a hereditary condition, it can also be caused by over-exercise in the formative months of development when the puppy’s bones are not yet set.
Symptoms include:
- A skipping gait where the dog occasionally holds up a back leg whilst walking, missing a step with that foot, but can then carry on as if nothing happened.
- Stiff, awkward gait in either one or both back limbs caused by the back legs not extending properly.
- A reluctance to run.
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2. Patella Luxation Testing
If you are concerned that your dog may be affected by Patella Luxation, consult your vet who will conduct a straightforward physical examination to check your dog’s patellas. All breeders should ensure that the sire and dam for any potential mating are tested for Patella Luxation prior to breeding.
Patella Luxation Testing is carried out by a vet who is familiar with the Putnam Patellar Luxation Grading System. The examination is normally performed during an orthopaedic examination without sedation. The vet will use the Putnam (1968) testing and scoring method to grade dogs with a score from 0 – 4 as follows:
- Grade 1: A kneecap that can be luxating with manual pressure but is otherwise is within the groove.
- Grade 2: The kneecap spontaneously luxates, is typically associated with a skipping lameness when the kneecap moves.
- Grade 3: The kneecap is permanently luxated but can be manually replaced in the groove.
- Grade 4: The kneecap is permanently luxated and cannot be manually replaced in the groove.
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Interpreting test results
A dog with a 0,0 score is the ideal.
If you are considering breeding your dog, we recommend that dogs scoring grade 2 or above on any patella should not be used for breeding as it’s possible the genes associated with the disease could be passed on to the puppies. This means that only dogs scoring ‘0’ or ‘1’ should be used in breeding programmes.
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Submission of results
Patella testing is one of the Club & the Kennel Club’s recommended mandaotry tests for the English Toy Terrier (B&T). However, the RKC does not record results from dogs that have been graded for Patella Luxation, and there is no formal scheme for them to accept results at this time.
The ETT Club may ask for information regarding these tests in future health surveys.
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Patella Luxation Report Form
Breeders can download our Patella Luxation Report Form for their vet to record scores and certify the results of any Patella Luxation Test. Breeders should request Patella scores from potential mating partners such as stud dogs and use the information provided to inform mating decisions. Puppy buyers should always ask to see the Patella Luxation scores for both parents of a puppy before committing to buy.
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3. Treatment
Treatment for Patella Luxation varies depending on the severity of the symptoms experienced by the dog and the grading level diagnosed by a qualified vet.
In milder cases, non-surgical treatments may suffice and may include ensuring the dog maintains a healthy weight, an appropriate and controlled exercise plan, physiotherapy or anti-inflammatory medication. In more severe cases (rare in English Toy Terriers) surgery may be required.
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4. Prevention
It is advisable that all puppy owners are careful not to over-exercise their dogs, and to prevent puppies from jumping from height to protect their young bones and joints that are still developing and not fully set. See our information on Exercise & Enrichment.
Patella Luxation is a hereditary issue in many small dog breeds and much work has been done, and must continue, to reduce the instances of Patella Luxation in English Toy Terriers. The 2022 UK Breed Health Survey for English Toy Terriers revealed a 4.3% incidence of Patella Luxation, an improvement from a 7.9% incidence reported in the survey conducted by the Canadian Manchester Terrier Club in 2018 which included Toy Manchester Terriers (the North American name for English Toy Terriers).
To further reduce the prevalence of Patella Luxation in English Toy Terriers, breeders must ensure that both sires and dams are tested and exclude affected dogs from breeding programmes. Patella Luxation is a hereditary health issue and can be bred out of our breed.