In the 1950’s increasing numbers of dog owners were finding very early hip arthritis to be a problem, some having symptoms from 2 years of age. The commonest breeds in which this was noticed were Labradors, Retrievers and German Shepherds; however, this may simply be because they were the most popular breeds and therefore the most numerous presenting to vets.
‘Dysplasia’ is a term frequently used to describe the general appearance of abnormal joint development but this is not specific to any single diagnosis. For example, an x-ray taken at skeletal maturity will show changes from healed trauma, growth plate injury and Perthes disease which can all look similar to genetic or congenital abnormalities. These conditions are acquired after birth and the genetics not proven despite decades of research.
The historic scoring methods are based on phenotypic features. A score given from x-rays does NOT include a diagnosis. One of the factors scored is Laxity, which breeders understand varies greatly between breeds and gender.
In human studies, joint laxity following trauma is highly correlated with early onset of osteoarthritis; however non -traumatic laxity has NOT been correlated with premature arthritis.
It is acknowledged that research involving dogs and other species has been for the benefited humans; Norberg (famous for the Norberg angle) used his knowledge of human joint disorders, stating in his original published work from the early 1960s ‘However, the Basic features are similar and for this reason one has the right to assume that the disease is basically the same in the two species.’
Sadly, it would seem that this principal has been in the main forgotten and rarely applied for the benefit of dogs.
From 1957 to 2018 there is still a failure to learn from Norberg and his colleagues who believed that: ‘environmental factors are responsible for at least 50 per cent of the variation of the severity of hip dysplasia. Is this largely down to selective use of their pioneering work?
Elbow ‘Dysplasia’ diagnosis is even more confusing with at least five different conditions all being labelled ‘Dysplasia’; probably with very different causes. The Pupscan pilot study for elbow disorders in dogs using Ultrasound imaging demonstrated that excellent diagnostic images could be obtained. Applying the same hypothesis as we did for hips will be the baseline for a parallel study for elbows
Slipping Patella is another condition that the team are considering for investigation as it again exists in humans and had been previously studied across species.