What are Growth Development Diseases (Developmental Orthopedic Diseases)? 

Poor nutrition is suspected to be a cause of Growth Development Diseases. When a dog has a high calorie intake it causes excess weight gain and in turn often rapid growth. When a Dane puppy’s growth is accelerated by their diet, their developing bones and bodies are unable to handle the rapid growth which in turn can lead to growth development diseases (Developmental Orthopedic Diseases). Among these diseases are Hypertrophic Osteodystrophy (HOD), Panosteitis (pano), and Osteochondritis Dissecans (OCD).

   Proper exercise and a quality diet may lessen the risk of these growth/nutritional diseases.

 Hypertrophic Osteodystrophy (HOD) – is a skeletal disorder of rapidly growing large and giant breed puppies. The most commonly affected bones are the ends of the long bones from the elbow to the wrist (the radius & ulna) and the ends of the long bone from the knee to the hock (the tibia). Both legs are usually affected at the same time by this disease.

Early signs of the disease can be splaying of the toes and dropping of the pasterns, lameness, and pain are also common.

 Symptoms of HOD can include joint enlargement lameness, lethargy, refusal of food, fever,   mild to moderate swelling of the growth plates in the leg bones, which usually is painful to the dog. If it is a severe case and left untreated the dog could endure permanent structural damage or even die.

There is currently no agreement on the cause or prevention of this disease. A few suspected possibilities to the cause of this disease could be a bacterial infection, vitamin C deficiency, as well as poor nutrition.

   Osteochondritis Dissecans (OCD) - It is a condition of abnormal cartilage growth seen in rapidly growing dogs. Usually occurs from 4-8 months during the stage of rapid skeletal growth.

Typically, as dogs mature the cartilage grows outward with the inner layer turning in to supportive bone. With OCD however, a focal area of cartilage does not turn into bone and remains abnormally thick. Cartilage cells cannot survive well at this thickness and they die, leaving a space between the cartilage and underlying bone. This space prevents the cartilage from “cementing” to the bone and provides no underlying support. As body weight is applied to the joint during normal activities cracks occur in the cartilage. Ultimately, a cartilage flap develops causing pain and lameness in affected dogs.

The exact cause is unknown. Genetics and over nutrition are thought to contribute contribute.

   Panosteitis (Pano) - Generally seen between 5-12 months of age, it is caused by excessive bone production on the long bones. Dogs will generally grow out of the problem, but it is a painful condition. Pano usually leaves no lasting ill affects on a dog.

Diet is suspected to play a role. Feeding high protein puppy diets may make the puppy grow too fast and increase the chance of a pup experiencing pano (sometimes described as "growing pains"). Pups usually completely outgrow Pano by 18 months.