Slipping Kneecaps in Cavaliers: What Australian Vet Records Found
In Australian vet records, 12.5% of Cavalier King Charles Spaniels had a slipping kneecap over ten years. Heavier dogs and ruby-coloured dogs had higher odds.
Written by thecanineledger
If your dog suddenly can’t put weight on a back leg, or is in pain, see your vet the same day. If your dog skips or hops on a back leg now and then, mention it at your next vet visit, or book sooner if it happens more often.
Our note: This advice is ours. The study notes that mild cases are often not reported because signs come and go.
Patellar luxation is a kneecap that slips out of its groove. In Australian primary-care records from 2008 to 2017, an estimated 12.5% of Cavalier King Charles Spaniels were diagnosed with it (Son et al., Veterinary Medicine and Science 2026). The authors cite a figure of 3.8% from a UK study.
While a slipping kneecap rarely threatens a dog’s life, it can mean lasting pain. The authors note that higher grades are linked to “pain, chronic lameness, disability” and other joint problems such as cruciate rupture and arthritis.
→ Cavalier King Charles Spaniel Health: Why the Heart Comes First
1. The study
The dogs. Researchers used VetCompass Australia, a database of primary-care vet records. They searched the records of Cavaliers for kneecap problems and checked a random sample of 735 dogs by hand. Of these, 721 were confirmed.
Which way it slipped. Where recorded, most kneecaps slipped inwards (medial), 270 dogs, rather than outwards, 11 dogs. For most dogs the direction wasn’t recorded.
Funding. No funding was provided for this study. The VetCompass Australia project is funded by Australia’s seven veterinary schools and the Australian government. The authors declare no conflicts of interest.
2. Which Cavaliers were most affected
Weight. Dogs weighing 11 to 13 kg had about 2.5 times the odds of dogs under 7 kg. The authors note that the breed standard in Australia is 5.4 to 8.2 kg.
Coat colour. Ruby-coloured dogs had about twice the odds of dogs of other colours.
Neutering. Neutered dogs had three times the odds of entire dogs. However, the authors suggest this may be because owners of neutered dogs see the vet more often.
Age. Dogs aged 10 or over had lower odds than young adults. The condition is often first found in young dogs.
Both knees. Dogs with both knees affected were more likely to have a higher grade.
Our note: The paper doesn’t explain why ruby-coloured Cavaliers might be at higher risk.
3. Weight: a conflicting finding
Heavier dogs here. In this study, dogs above the breed-standard weight were more likely to be diagnosed.
Lighter dogs in the UK. The authors note this is “in opposition to the findings of the UK study”, which found lighter dogs at higher risk.
Weight isn’t the same as fat. The authors point out that a high bodyweight “does not necessarily suggest a high body condition score”. Body condition was rarely recorded.
Our note: The evidence on weight and knee problems here is mixed.
→ Is My Dog Overweight? Body Condition Scoring Without Guesswork
4. What the study can’t tell you
Grading. The grade was recorded for 66.9% of dogs, and the authors assumed vets used a standard grading scale.
Mild cases missed. Mild kneecap problems often go unreported because the signs come and go.
Figures that differ. The abstract gives the odds for dogs aged 10 or over as 0.44; the results give 0.43.
5. If you have, or want, a Cavalier
- Ask the breeder whether the parents’ knees have been checked.
- Watch for skipping on a back leg, and tell your vet.
- Ask your vet to check the kneecaps at routine visits.
Our note: These points are ours.
→ Choosing a Breed or a Mix: The Health Data Breeders Don’t Lead With · → Cruciate Ligament Rupture: Surgery, Conservative Care, and the Evidence Gap
6. What we could not verify
| Commonly said | What we found |
|---|---|
| “Only toy breeds get slipping kneecaps” | Not tested here. This study looked only at Cavaliers. |
| “Overweight causes slipping kneecaps” | Not settled. Heavier Cavaliers had higher odds here, but a UK study found the reverse. |
| “Neutering causes it” | Not shown. Neutered dogs may simply see the vet more. |
Sources
- Son Y, Keller MD, Williamson P, Taylor RM. Prevalence and grade of patellar luxation in Cavalier King Charles Spaniels attending primary-care veterinary practices in Australia. Vet Med Sci 2026: VetCompass Australia records, 2008 to 2017. No study-specific funding
Always confirm with your vet before acting on anything on this page.