The Cavalier King Charles Spaniel – born to suffer?A happy, active, always motivated and cute looking family dog in handy size. With these characteristics the Cavalier King Charles Spaniel would be the perfect four-legged partner in many households. Therefore, it is not surprising that it is one of the most popular companion dogs.
Unfortunately, the breed struggles with numerous health problems. These include the frequent occurrence of heart disease, epilepsy and various eye diseases. Also, many of the Cavaliers suffer from the dreaded syringomyelia. 1 2 3
Syringomyelia is a disease of the spinal cord. The spinal cord is a tubular tube inside the spinal column made up of nerves. It processes and transmits messages from the brain, sensory receptors, muscles and glands. In dogs suffering from syringomyelia, fluid-filled cavities form in the spinal cord. This leads to increased damage to the nerves of the spinal cord with numerous serious consequences 4 5 . Suffering cavaliers often suffer from neck and shoulder discomfort, which results in prolonged scratching attacks. Further, they often become very sensitive to touch in the head and neck area. With increasing duration of the disease, many of the cavaliers with syringomyelia suffer from massive, excruciating nerve pain and neurological deficits
That worldwide many specimens of the breed are affected by syringomyelia is supported by several studies 6 7 . A working group of the Justus-Liebig University in Giessen examined more than 200 Cavaliers of different ages from Germany. Fifty-seven percent of the dogs surveyed had syringomyelia in the process 8 . In a dissertation that looked at the incidence of syringomyelia in the German cavalier population, 48.1 percent of the 339 cavaliers surveyed had the disease 9 .
From the results, it could be concluded that just under half of Cavalier Spaniels have syringomyelia. But this is only the tip of the iceberg. A study of 555 Cavalier Spaniels from the Netherlands and England showed that with each year of the Cavalier's life, the proportion of affected dogs increases. At the age of 12 months, only 25 percent of the animals showed syringomyelia. In 6-year-olds, a full 70 percent were then affected. 10 .
So while a high number of cavaliers worldwide suffer from syringomyelia, there is another nervous system condition that is even more common. In this condition, the cerebellum has too little space in the skull. So the brain is too big for the dog's skull. As a result, parts of the brain are squeezed through the occipital hole. The occipital hole is a large opening in the skull through which the connections of blood and nerve vessels run between the brain and the spinal cord. The brain emerging from the skull and squeezing off parts of the elongated spinal cord and obstructing the normal flow of spinal fluid 11 . Since this clinical picture resembles the so-called Chiari malformation of humans, it is called Chiari-like malformation.
Almost all Cavalier King Charles Spaniels have this malformation. The breed is characterized by a cute childlike looking round head shape. Purposefully breeding out this trait may be responsible for the inappropriate brain size in relation to the skull 12 . In a population of 329 German cavaliers, a startling 97.1 percent had a Chiari-like malformation. Also, all other studies on the spread of the disease so far resulted in the fact that almost all specimens of the breed are affected by the cranial deformity 6 7 13 . Chiari-like malformation can also lead to a whole range of symptoms that significantly impair the quality of life of the animals and are accompanied by considerable suffering. 14
This includes, for example, tiring them out quickly. Many of them rub their head intensively on the ground. Back pain and pain-related difficulty walking up or down stairs or jumping may also occur. Cries of pain that occur spontaneously or are triggered by lifting are also characteristic. Intensive touching near the back or turning the head is extremely uncomfortable for some of the affected Cavaliers. Nerve crushing can lead to temporary paralysis in some cases. To the failure of various body regions. Furthermore, temporary strabismus may occur as part of the disease. Undirected aggression behavior come. It is also discussed whether the Chiari-like malformation contributes to the development of syringomyelia 15 .
It should be noted: Almost all Cavalier King Charles Spaniels have the cranial malformation in the form of a Chiari-like malformation. But not all of them show clearly recognizable symptoms. Can these animals be amed to be free of complaints? I find this question difficult to answer.
People suffering from this type of Chiari malformation have severe headaches in more than 80 percent of the cases. Physical stress. Sneezing usually makes them worse. A large proportion of patients also struggle with visual disturbances, balance problems, dizziness and temporary hearing loss. 16 . At this point, the problems related to the dog become clear. Because it is difficult for a dog to express if it is affected by headaches, dizziness and visual disturbances. Possibly suffering silently. We do not notice it. 17
A small study provides first indications that this could be the case. In the work the researchers compared the gait of Cavaliers with that of Border Terriers. All participating cavaliers were affected by Chiari malformation, but only some of them showed syringomyelia. Computerized gait analysis was used in the process. This also provides information that escapes the human eye alone. So the movements of the dogs can be more exact. Be better judged. In all cavaliers, in contrast to the group of border terriers, abnormalities of gait were observed. Cavalier King Charles Spaniels without syringomyelia also had these abnormalities. The movement pattern and subtle coordiation disturbances exhibited by the animals are actually typical of dogs with spinal cord injuries or cerebellar damage 11 . If you look at this impairment with the naked eye? No. Nevertheless impairments are present. What if many of the cavaliers suffer unnoticed headaches just like people with a Chiari malformation?
On a sober note, the summary is: At this point, dogs are being selectively bred as part of the Cavalier King Charles Spaniel breed, whose skulls are too small for their brains to handle. Currently, there is neither a concrete breeding program against this malady nor an increased awareness of the Chiari-like malformation, which affects almost all cavaliers.
Cover photo by Luca Montanari
Lewis T, Swift S, Woolliams JA, Blott S. Heritability of premature mitral valve disease in Cavalier King Charles spaniels. Vet J. 2011;188(1):73-6. doi: 10.1016/j.tvjl.2010.02.016 Rusbridge C (2005): Neurological diseases of the Cavalier King Charles spaniel. Journal of Small Animal Practice 46: 265-272.
Summers J, O'Neill D, Church D, Thomson P, McGreevy P, Brodbelt D. Prevalence of disorders recorded in cavalier king Charles spaniels attending primary-care veterinary practices in England. Canine Genetics Epidemiol. 2015;2(1):4. doi: 10.1186/s40575-015-0016-7
Hartley C, Donaldson D, Smith KC, Henley W, Lewis TW, Blott S, et al. Congenital keratoconjunctivitis sicca and ichthyosiform dermatosis in 25 Cavalier King Charles spaniel dogs. Part I: clinical signs, histopathology, and inheritance. Vet Ophthalmol. 2012;15(5):315-26.
Rusbridge, C, 2005:Neurological diseases of the Cavalier King Charles spaniel. Journal of Small Animal Practice 46: 265-272.
Rusbridge, C, 2007:Chiari-like malformation with syringomyelia in the Cavalier King Charles Spaniel: long-term outcome after surgical management. Veterinary Surgery 36: 396-405
Couturier J, Rault D, Cauzinille L (2008): Chiari-like malformation and syringomyelia in normal cavalier King Charles spaniels: a multiple diagnostic imaging approach. Journal of Small Animal Practice 49: 438-443.
Cerda-Gonzalez S, Olby NJ, McCullough S, Pease AP, Broadstone R, Osborne JA (2009c): Morphology of the caudal fossa in Cavalier King Charles Spaniels. Veterinary Radiology& Ultrasound 50: 37-46.
Schulze, Sabine& Refai, Miriam& Germany, Martin& Failing, Klaus& Schmidt, Martin. (2018). Prevalence of syringomyelia in clinically unaffected Cavalier King Charles Spaniels in Germany (2006-2016). Veterinary practice. Ie K, Small Animals/Pets.
Refai, Miriam (2017). Prevalence of Chiari-like malformation and syringomyelia in Cavalier King Charles spaniels in the Federal Republic of Germany. Giessen : VVB Laufersweiler publishing house
Parker, J. E., Knowler, S. P., Rusbridge, C., Noorman, E., & Jeffery, N. D. (2011). Prevalence of asymptomatic syringomyelia in Cavalier King Charles spaniels. Veterinary Record, 168(25), 667-667
Olsen, Emil; Suiter, Emma Jane; Pfau, Thilo; McGonnell, Imelda M.; Matiasek, Kaspar; Giejda, Anna; Volk, Holger Andreas (2017): Cavalier King Charles Spaniels with Chiari-like malformation and Syringomyelia have increased variability of spatio-temporal gait characteristics. In: BMC Veterinary Research, Vol. 13, 159
Driver CJ, Volk HA, Rusbridge C, Van Ham LM. An update on the pathogenesis of syringomyelia secondary to Chiari-like malformations in dogs. Veterinary Journal 2013;198:551-559.
Dewey CRC. Treatment of canine Chiari-like malformation and syringomyelia. In: Bongura J, Twedt DC, editors. Kirk's current veterinary therapy. St Louis (MO): Saunders Elsevier; 2008. p. 1102-7.
Rusbridge C. Behavioural and clinical signs of Chiari-like malformation and syringomyelia in cavalier King Charles spaniels. In: 61st Congress of the BSAVA, Birmingham: British Small Animal Veterinary Association Congress ISBN (2018)
Wijnrocx K, Van Bruggen LWL, Eggelmeijer W, Noorman E, Jacques A, Buys N, et al. (2017) Twelve years of chiari-like malformation and syringomyelia scanning in Cavalier King Charles Spaniels in the Netherlands: Towards a more precise phenotype. PLoS ONE 12(9): e0184893.
Milhorat TH, Chou MW, Trinidad EM, Kula RW, Mandell M, Wolpert C, Speer MC (1999): Chiari I malformation redefined: clinical and radiographic findings for 364 symptomatic patients. Journal of Neurosurgery 45: 1005-1017
Knowler SP, Galea GL, Rusbridge C Morphogenesis of canine Chiari malformation and secondary syringomyelia: disorders of cerebrospinal fluid circulation. Frontiers of Veterinary Science..