Osteogenesis Imperfecta in Dogs

This severe  skeletal disorder is most common in Beagles, Standard Wirehaired Dachshunds,Golden Retrievers, Poodles, Bedlington Terriers, Norwegian Elkhounds, and  the Standard and Miniature Smooth haired Dachshund. A canine who is having trouble walking, shows that he is in pain, is developing muscle atrophy, and has difficulty breathing may have osteogenesis imperfecta. This condition has no cure; veterinary care is essential to determine if your pet has this illness.

An autosomal recessive trait, osteogenesis imperfecta, also known as “Brittle-bone disease”, is an inherited disease that results in fragile bones, joints and teeth. This disease occurs as a result of a mutation in certain genes that are involved in the correct folding and formation of collagen fibers. 

As this disease is due to poor collagen formation, common clinical signs detected are:

• Spontaneous fracturing of the bones and teeth
• Loose joints 
• Difficulty walking
• Pain
• Osteopenia (reduction in bone mass)
• Sclera of the eye may be blue
• Growth is stunted
• Loss of hearing
• Weak tendons
• Weak muscles and muscle atrophy may develop 
• Malformation of bones due to progressive healing of fractures

In more severe cases:

• Ribs may break 
• Difficulty breathing

This disorder is completely inherited and so it is essential owners know the genetics of both parents. Some of the crosses may work as such:

• If one parent is a carrier of the gene and the other is not, there is a 50:50 chance that offspring will develop the disease.
• If one parent is affected with the disorder and the other parent is clear from the disorder then the offspring will have a 100% chance of contracting brittle bone disease.

This concludes that a dog can be a carrier for one copy of the gene that encodes brittle bone and as a result if bred with another carrier then there is a 25% chance of their offspring developing the disease.

X-rays will be done and will show multiple bone fractures that have occurred recently, as well as fractures in the process of healing. Radiographs will also show a decrease in bone density. Your veterinarian will take a buccal (cheek) swab and can send these samples to the laboratory in order to determine if your dog is a carrier for the gene.

Blood tests may be done to determine levels of calcium, vitamin D, phosphorus and parathormone as abnormal levels indicate the possibility of brittle bone disease. Veterinarians may also take a biopsy of skin; this is done in order to determine the presence and abnormality of type -1 collagen in dogs.

There is no cure for osteogenesis imperfecta. In severe cases, animals may have to be euthanised. However, for milder cases corrective orthopedic surgeries may be done in order to fix small fractures. One possible method of management may be to prescribe pain relievers to decrease pain and encourage fracture recovery. It may be possible that dogs will be placed on a wet/soft food diet should their teeth be to brittle to consume hard kibble.

As there is no cure for the disorder owners need to be aware that their pets will require special needs. Exercise may need to be limited due to the increased frequency that fractures may occur. 

Studies done on kittens diagnosed with Osteogenesis imperfecta suggest that Vitamin C supplements and alendronate may be given as well in order to aid with recovery of fractures. It can be claimed that Vitamin C aids is support and recovery of collagen fibers. Alendronate and possible biophosphate have been shown to increase bone reabsorption and structure in human studies and may be possibly used to treat pets. However, there are few studies explaining the treatment plans and recovery for osteogenesis imperfecta.

This is a common method of treatment in humans and is slowly being progressed to pets. As there is no treatment, it is best that when breeding dogs breeders should conduct OI DNA tests in order to prevent the disease from spreading to offspring.