The Prevalence of Coxofemoral Osteoarthritis in Small Dog Breeds and HD Screening in Cairn Terries A Clinical Radiological Study

Abstract

Background: The prevalence of coxofemoral osteoarthritis being very high, > 40 %, in some large dog breeds. The aim of the study was to estimate the prevalence of osteoarthritic changes in the hip joints in small dog breeds and study the clinical relevance of Hip Dysplasia scoring in Cairn Terries in Denmark. Methods:In a five-year-period study of 2423 small dog breeds (< 15 kg) at the University Hospital, Copenhagen the prevalence of osteoarthritis in the hip joints was calculated A full clinical examination was performed and hip joint radiographs taken in 18 Cairn Terriers, earlier officially scored for hip dysplasia by The Danish Kennel Club, 13 of them with a score of C, D or E respectively. Results:The prevalence of coxofemoral osteoarthritis in small dog breeds was found to be 0.5 %, which is in accordance with earlier published studies in small dog breeds in other countries.In 18 Cairn Terriers, no correlation was found between the initial Hip Dysplasia scoring and clinical signs indicating discomfort. No evidence of osteoarthritis and no progression of hip joint laxity or deformation could be found on the follow up radiographs taken > 18 months (mean. 38 months) after the initial radiological examination evaluated for official HD screening. Conclusion:Due to the very low prevalence in osteoarthritis in small dog breeds and low clinical significance of the radiological scoring of the hips in Cairn Terrier according to parameters set by FCI it cannot be recommended to use the same parameters in Cairn Terrier as in large dog breeds in routine screening programmes for Hip Dysplasia in Cairn Terriers. Keywords Material & MethodsThe prevalence studyFor presence of osteoarthritis changes (malformation of femoral head, acetabulum, sclerosis, periarticular new bone formation) was performed retrospectively on radiographs of purebred small dogs (> 1 year of age, body weight < 15 kg) taken at the Small Animal Hospital at University of Copenhagen in a period of 5 years (2006 -2010). During this period, a total of 2423 small pure breed dogs were presented for all kind of consultation. From these 229 Ventro-Dorsal radiographs of the pelvic area from 37 different pure breeds were included in the study (Table 1). Table 1 shows the material of dogs on which the prevalence's are calculated and organized in relations to different breeds and the prevalences in the different breeds showing the average prevalence to be 0.5 %. The Shetland Sheepdogs and the French bulldog hawing the highest individual prevalence, 3.9 and 1.9 respectively. Dachshound, Miniature Schnauzer, Papillon and Yorkshire Terrier having 0.0 % in this material.To be able to evaluate if there is an age or gender related prevalence of osteoarthritic changes, the dogs were separated in 4 groups (12 -35 months and > 36 months and gender groups).The age and clinical findings were recorded. Dogs were excluded if affected by Legg-Calve-Perthes disease, femoral head excision or a fracture or luxation of the pelvic bones. If the same dog was examined more ...