Hypertrophic Osteodystrophy (HOD)

This bone disease usually affects young, rapidly growing, large breed canines. It also goes by many names — skeletal scurvy, Moller-Barlow’s disease, osteodystrophy II or metaphyseal osteopathy. HOD causes severe lameness and pain and can affect multiple limbs. The cause is currently unknown.

HOD usually strikes puppies between the ages of 3 to 6 months. It tends to strike male dogs more than females. It is common ailment among all large breeds of dogs, and, at the moment, there doesn’t appear to be a genetic or inherited link.

If your dog is suffering with HOD, you may notice a mild to moderate painful swelling of the growth plates in your dog’s leg bones. It most commonly starts at the end of the radius, ulna (the bone between the elbow and the wrist) or the tibia (the bone from the knee to the hock). This can cause his leg to look lame and show a reluctance to move. He may be lethargic and refusing to eat. A fever can also accompany HOD. It usually affects both legs at the same time. The symptoms may wax and wane all on their own and even resolve itself. However if the fever (of up to 106 degrees) is so high for too long or the damage so severe, your dog may suffer permanent structural damage to his legs and could even die.

An official diagnosis will be based on a physical exam and through x-rays. If your dog has a fever, a blood cell count should be high.

Treatments will include anti-inflammatories to help with the pain. As well, a broad spectrum antibiotic is prescribed. Strict rest in a warm bed is strongly recommended. Feeding your dog a highly palatable, nutritious food should encourage him to eat. In severe cases, your dog may be prescribed steroids or a vitamin C supplement to control the pain.

The cause of HOD is unknown. Some vets believe HOD may be a bacterial infection. The bony changes and high fever support this theory. HOD tends to mimic the symptoms of scurvy in humans — which is a vitamin C deficiency. However not all affected dogs who take a vitamin C supplement show improvement. This leads researchers to speculate the low blood level of vitamin C is a result of HOD and not a cause.

Additionally other research suggests a possible cause is nutrition. Several bone diseases in young puppies have been linked to an excess of protein and/or calories in their diet. There haven’t yet been any studies to link HOD to diet. However, many owners of large or giant breed canines are encouraged to feed their dog a diet low in fat and protein to try to encourage moderate and steady growth instead of rapid growth.

At this time, an exact cause of HOD and a prevention plan of this painful and debilitating disease is unknown.