Diffuse Idiopathic Skeletal Hyperostosis in the dog

Abstract

Abstract Study design: A retrospective radiographic cohort study. Objective: To determine the prevalence of diffuse idiopathic skeletal hyperostosis (DISH) in a out-patient population of dogs (age > 1 year). Summary of Background data: DISH is a systemic disorder of the axial and peripheral skeleton which is common in humans but still unrecognised in dogs. The etiology of DISH in humans is unknown and the condition occurs in middle aged and elderly human patients. It results in ossification of soft tissues such as longitudinal spinal ligaments, joints, sites of attachment of tendons, muscles and/or capsules to bone. Symptoms can vary from mild back pain and little stiffness to more serious symptoms such as neurologic deficits and spinal fractures. The disorder is incidentally described in veterinary literature in dogs and may be difficult to distinguish from spondylosis deformans. Methods: Radiographs of 2041 dogs over 1 year of age, visiting the University Clinic for Companion Animals in Utrecht between February 2003 and January 2008, were reviewed for DISH in the spine, using the criteria stated by Resnick et al (1976). Four or more level involvement was defined as DISH. Three-level involvement was defined as pre-stage DISH and recorded separately. Results: The overall prevalence of DISH in a cohort of 2041 dogs was 3.8%. The prevalence of DISH increased with age; in dogs over 7 years the prevalence of DISH was 5.7%. In male dogs this was 7.1% and in female dogs 4.4%, resulting in a male dog-female dog ratio of 1.6 to 1. Boxers were most frequently affected by DISH; the prevalence in Boxers over 7 years old was more than 50%. Conclusions: DISH seems to be a prevalent disorder in dogs. The overall prevalence in this animal out-patient population is 3.8%. Boxers are most commonly affected, which may indicate a genetic susceptibility for DISH.

Key words: diffuse idiopathic skeletal hyperostosis, DISH, dogs, prevalence, Boxer, spondylosis deformans.