10.03.2021: Hip dysplasia is one of the most frequently occurring orthopaedic diseases in dogs. The earlier hip dysplasia is diagnosed, the sooner the animals can be treated and the better that treatment will be. A recently published study by Vetmeduni involving Rottweilers from the Austrian Armed Forces investigated at what point a reliable early diagnosis can be made. In the present study, early diagnosis was possible from the age of about 35 weeks.
Canine hip dysplasia (CHD) is a multifactorial disorder characterized by hip joint laxity at a young age and subsequent development of osteoarthrosis. CHD is usually diagnosed after skeletal maturity is reached at around 12 months of age, or later in very large breeds. The early diagnosis of canine hip laxity as a sign of hip dysplasia is of great importance in small animal orthopaedics, as it enables breeders and trainers of working dogs (e.g. guide dogs for the blind, police dogs, etc.) to assess and select the animals based on their health for suitability in later tasks. The early diagnosis of a predisposition to CHD could also allow therapeutic interventions to reduce the severity of the disease and/or the development of osteoarthrosis.
Several research groups around the world are already working on methods to enable the early diagnosis of hip dysplasia in young dogs. Most of these methods involve a combination of orthopaedic examinations and special radiological diagnostics. According to most of the literature published on the subject, a reliable diagnosis for determining the probability of subsequent hip dysplasia can be made as early as four to five months of age.
International assessment methods for early detection of hip dysplasia
The present study examined a group of Rottweilers from the Austrian Armed Forces at four, eight and twelve months of age to evaluate the correlation between clinical orthopaedic examinations and the final scoring according to the Fédération Cynologique Internationale (FCI) guidelines for hip dysplasia at the age of twelve months.
Three different orthopaedic tests (Ortolani, Barlow and Bardens) were performed on the dogs at each of the examination times. A positive test indicates increased hip laxity. Various joint angles (subluxation and reduction angles) were also measured to allow a quantitative assessment of joint laxity. The final scoring was then performed at twelve months of age using an FCI radiological evaluation. Data analysis was performed with various statistical methods to assess whether the results of the examinations at four and eight months were predictive of the degree of hip dysplasia at twelve months.
Last author Masoud Aghapour summarizes the results of the study as follows: “Two of the methods used – the Ortolani test and the reduction angle – showed good predictive value for the later degree of hip dysplasia when performed at the age of eight months. A reliable diagnosis in relation to the FCI scoring could not be made for Rottweilers at four months of age.” These findings are not entirely consistent with those of previous studies, which may be due to several factors. First author Britta Vidoni points out that the present study examined a relatively small number of animals and that only a few animals eventually developed severe CHD. This circumstance in particular may account for the fact that no statistically significant statement could be made at four months. Nevertheless, dogs graded at HD C or worse at twelve months of age also showed a clear tendency towards CHD in the examinations performed at four months.
These findings contribute significantly to the topic of canine hip dysplasia. The early diagnosis of increased hip laxity in puppies would allow veterinarians to plan preventive procedures to treat CHD or to reduce the severity of the disease in old age. These procedures would improve the quality of life of the dogs, reduce the incidence of osteoarthritis and so lower the resulting treatment costs. This is also of interest to breeders and trainers as it enables the early selection of breeding and working animals and improves the quality of both breeding and working dogs.
The article “Early Diagnosis of Canine Hip Laxity: Correlation between Clinical Orthopedic Examinations and the FCI Scoring Method in a Closed Cohort of Rottweilers” by Britta Vidoni, Veronika Bauer, Barbara Bockstahler, Michaela Gumpenberger, Alexander Tichy and Masoud Aghapour was published in animals.