Syringomyelia and Craniocervical Junction Abnormalities in Chihuahuas

Background: Chiari-like malformation (CM) and syringomyelia (SM) are widely reported in Cavalier King Charles Spaniels and Griffon Bruxellois dogs. Increasing evidence indicates that CM and SM also occur in other small and toy breed dogs, such as Chihuahuas. Objectives: To describe the presence of SM and craniocervical junction (CCJ) abnormalities in Chihuahuas and to evaluate the possible association of CCJ abnormalities with SM. To describe CM/SM-related clinical signs and neurologic deficits and to investigate the association of CM/SM-related clinical signs with signalment, SM, or CCJ abnormalities. Animals: Fifty-three client-owned Chihuahuas. Methods: Prospective study. Questionnaire analyses and physical and neurologic examinations were obtained before magnetic resonance and computed tomography imaging. Images were evaluated for the presence of SM, CM, and atlantooccipital overlapping. Additionally, medullary kinking, dorsal spinal cord compression, and their sum indices were calculated. Results: Scratching was the most common CM/SM-related clinical sign and decreased postural reaction the most common neurologic deficit in 73 and 87% of dogs, respectively. Chiari-like malformation and SM were present in 100 and 38% of dogs, respectively. Syringomyelia was associated with the presence of CM/SM-related clinical signs (P = 0.034), and medullary kinking and sum indices were higher in dogs with clinical signs (P = 0.016 and P = 0.007, respectively). Conclusions and Clinical Importance: Syringomyelia and CCJ abnormalities are prevalent in Chihuahuas. Syringomyelia was an important factor for the presence of CM/SM-related clinical signs, but many dogs suffered from similar clinical signs without being affected by SM, highlighting the clinical importance of CCJ abnormalities in Chihuahuas.</p

Development of a questionnaire to measure the effects of chronic pain on health-related quality of life in dogs

Objective—To develop a reliable, validated questionnaire that can be used for the assessment of chronic pain and its impact on health-related quality of life (HRQL) in dogs. Sample Population—17 owners of dogs that had chronic pain associated with chronic degenerative joint disease and 165 other dog owners. Procedures—Psychometric methods were used to identify relevant domains, create an item pool, select and validate items, and construct and preliminarily test a structured questionnaire. Relevant domains were identified through semi structured interviews. Descriptor-generating exercises provided the terms owners used to describe these domains and formed an item pool. A selection from this pool was validated and used to construct a questionnaire that underwent preliminary testing. Results—The structured questionnaire contained 109 simple, familiar, descriptive terms associated with good health or chronic pain (most describing subtle aspects of behavior that owners interpreted as expressions of subjective experiences of their dogs) for 13 possible HRQL domains. Each descriptor was associated with a 7-point numeric scale. Conclusions and Clinical Relevance—The questionnaire was intended to facilitate rapid, sensitive, and accurate rating of a comprehensive range of relevant domains by naïve raters with minimal burden on respondents. The principles underlying the development and design of this structured questionnaire offer a novel approach to the proxy measurement of HRQL and changes in HRQL associated with chronic pain for a range of animal species. Impact for Human Medicine—This novel approach may be applicable to other nonverbal populations (eg, young children or elderly people with cognitive impairment)