Bone Inflammation (Hypertrophic Osteodystrophy) in Dogs

The rapid growth rate of some puppies and juvenile dogs can cause abnormalities in their bones, such as with hypertrophic osteodystrophy. With hypertrophic osteodystrophy, your puppy’s legs (usually only the front two) get swollen around the growth plates most often in the radius, tibia, and ulna. The bones that are the most severely influenced are the ones that grow the fastest. Although it primarily only affects the front two legs, it can also occur in the paws, ribs, and jaw. This is usually seen within the first few months of life, but some dogs do not have any signs of it until they are two or three years old. It is an incredibly painful disease that can be bad enough to make the dog lame, and if the damage is severe, it can cause permanent disability. The cause is still unknown, but veterinary experts suspect a diet high in protein, low vitamin C levels, or a reaction to an immunization shot may have something to do with it. This disease is self-regulating and will run its course and be gone in a short amount of time in most cases. Once the bones are finished growing, the symptoms and signs will go away with no lasting problems in most dogs.

Bone inflammation (hypertrophic osteodystrophy) is a developmental disease that is characterized as a disorder of the development of the long bones where growth occurs in the front legs of puppies and juvenile dogs. This occurs most often in large and giant breeds, such as the Great Dane, German Shepherd, and Weimaraner, but it has been seen in other breeds as well.

In the beginning, you may only notice a slight limp in your dog and pain when you touch the affected areas. The symptoms will become more obvious as the disease progresses. Pain and swelling of the front legs are the most obvious signs, but this depends on the severity of the disease.

• Reluctance to move
• Pain in joints
• Mild or severe lameness (inability to walk)
• Unable to stand
• Arching of the spine (roaching)
• Loss of appetite
• Significant weight loss
• Depression/sadness
• High fever (could get up to 106 degrees)
• Dehydration
• Diarrhea
• Pneumonia

Although the cause of hypertrophic osteodystrophy is still not clear, some medical experts have suggested that it may be a severe reaction to certain immunizations, such as the canine distemper virus immunization. There has been some research that shows an increased amount of cases of hypertrophic osteodystrophy following the administration of modified live vaccines. However, this is only speculation because the immunizations happen to coincide with the age of rapid growth in many dogs. A lack of vitamin C is also a suspected cause, as well as an excess of other vitamins, besides vitamin C (i.e. calcium).

There is a higher incidence of hypertrophic osteodystrophy in large and giant breed dogs, which is believed to be due to the rapid rate of growth they go through. This disease is also more common in males than females. There is a high potential for this disease in Weimaraners, and the disease is often more severe in this breed. Some of the breeds most at risk are:

• Weimaraner
• Boxer
• Great Dane
• German Shepherd
• Basset Hound
• Irish Setter
• Doberman Pinscher
• Labrador Retriever

Since this affects puppies and juveniles most often, the veterinarian will immediately suspect hypertrophic osteodystrophy if you have a large or giant breed dog. The first thing the veterinarian will do is to get a complete history of your dog, do a thorough physical examination, and run some tests to rule out all other possible diseases. These tests are:

• Complete blood count (CBC)
• Blood chemistry panel
• Blood glucose level (amount of sugar in the blood)
• Electrolyte panel
• Urinalysis
• Bacterial and fungal cultures
• Digital radiographs (x-rays)

Your veterinarian may also want to get some other tests done if more information is needed. Some of those tests are:

• CT scan
• Ultrasound
• MRI

If the disease is severe, your veterinarian may admit your dog to the hospital to be cared for until he can walk, eat, and drink on his own. A feeding tube and IV therapy will be administered as well as pain medication (i.e. tramadol) and corticosteroids (i.e. prednisone). Because there is no cure and it is self-limiting, the main objective for your dog is pain relief. Your veterinarian will prescribe anti-inflammatory medication ((i.e. NSAIDS), pain medicine (i.e. tramadol), and possible some corticosteroids (i.e. prednisone). Vitamin supplements may also be prescribed as well as antibiotics if the veterinarian suspects an infection.

The prognosis for your dog depends on the severity of the disease. Recovery is usually very good for most dogs, and since it cures itself when your dog is done growing, you can look forward to it ending soon. Be sure to follow up with the veterinarian and take your dog for regular check-ups.