Craniomandibular Osteopathy (Terrier Type)

Test Overview:

Sometimes called “Westie jaw” or “Scottie jaw” by breeders, this is a disease most commonly seen in young West Highland white terriers, Scottish terriers and Cairn terriers that is thought to be inherited as an autosomal recessive trait. The disease causes proliferation of the lower jaw bone, as well as the tympanic bullae (part of the inner ear bones), and can sometimes affect other bones of the head. This causes abnormal enlargement of the bones when the bones are growing (i.e. when the dog is young), and can lead to some problems with chewing and swallowing, and difficulty opening the mouth. Some affected puppies will have pain when opening their mouth. This is usually a self-limiting disease, seen in dogs less than a year old. Excessive bone growth slows and then stops at around a year of age, and in some cases may even recede somewhat. Often treatment is symptomatic only, with soft foods and antiinflammatories/pain relief.


Musculoskeletal - Associated with muscles, bones and associated structures



Variant Detected:



Low-Moderate. This disease can cause some discomfort and/or dysfunction in the affected animal. It does not generally affect life expectancy.

Mode of Inheritance:

Autosomal Recessive

Research Citation(s):

2018 Vagt, J., Distl, O. : Complex segregation analysis of craniomandibular osteopathy in Deutsch Drahthaar dogs. Vet J 231:30-32, 2018. Pubmed reference: 29429484. DOI: 10.1016/j.tvjl.2017.11.008.
2016 Hytönen, M.K., Arumilli, M., Lappalainen, A.K., Owczarek-Lipska, M., Jagannathan, V., Hundi, S., Salmela, E., Venta, P., Sarkiala, E., Jokinen, T., Gorgas, D., Kere, J., Nieminen, P., Drögemüller, C., Lohi, H. : Molecular Characterization of Three Canine Models of Human Rare Bone Diseases: Caffey, van den Ende-Gupta, and Raine Syndromes. PLoS Genet 12:e1006037
2016. Pubmed reference: 27187611. DOI: 10.1371/journal.pgen.1006037. Hytönen, M.K., Lohi, H. : Canine models of human rare disorders. Rare Dis 4:e1241362, 2016. Pubmed reference: 27803843. DOI: 10.1080/21675511.2016.1241362.
2012 Pettitt, R., Fox, R., Comerford, E.J., Newitt, A. : Bilateral angular carpal deformity in a dog with craniomandibular osteopathy. Vet Comp Orthop Traumatol 25:149-54, 2012. Pubmed reference: 22366888. DOI: 10.3415/VCOT-11-02-0022.
2011 Thompson, D.J., Rogers, W., Owen, M.C., Thompson, K.G. : Idiopathic canine juvenile cranial hyperostosis in a Pit Bull Terrier. N Z Vet J 59:201-5, 2011. Pubmed reference: 21660851. DOI: 10.1080/00480169.2011.579556.
2010 Ratterree, W.O., Glassman, M.M., Driskell, E.A., Havig, M.E. : Craniomandibular osteopathy with a unique neurological manifestation in a young Akita. J Am Anim Hosp Assoc 47:e7-12, 2010. Pubmed reference: 21189419. DOI: 10.5326/JAAHA-MS-5464.

Associated Breed(s):

Australian Shepherd, Cairn Terrier, Mixed Breed, Scottish Terrier , West Highland White Terrier ,