Breeds – Large and giant breeds, especially German shepherd dogs and Bassett hounds
Gender – Males are more commonly affected, but females are also affected
Age – 5 months up to 2 years (although it is uncommon after 1 year of age)
Etiology – Unknown, but nutrition and genetics may play a role. A viral cause has also been postulated.
Mild to moderate lameness, often moves between different limbs, may be lethargic with decreased appetite
Mild to moderate lameness, pain on palpation of diaphysis of long bones
Radiographs are helpful, but not always diagnostic depending on stage. There may be attenuation of trabecular patterns in the proximal and distal aspects of the diaphysis. This may be followed by the development of patchy densities, especially around the nutrient foramen of bones. The periosteum may demonstrate reactive changes, followed by thickening of the cortices. CT may also be helpful.
Rest, nonsteroidal anti-inflammatory drugs, change to large dog growth diet or adult dog food
Hypertrophic osteodystrophy (Metaphyseal osteopathy)
Breeds – Medium and large breeds of dogs, especially Great Danes, Irish Setters, boxers, Labrador retrievers, Weimaraners
Gender – Males may be predisposed
Age – 2 to 6 months of age
Etiology - The cause is unknown, but recent studies in Weimaraners suggest it may be an immune-mediated condition. Other potential causes include bacterial, viral, or post-vaccination. Vitamin C deficiency has long been mentioned, but there is no proof of this, and treatment does not seem to affect the course of the disease.
Affected dogs may often have a history of lethargy, anorexia, pain, reluctance to move, and lameness.
Lethargy, pyrexia, lameness, a roached back appearance while standing, swelling and pain on palpation of metaphyseal regions of long bones, anorexia.
Radiographs are often diagnostic. Changes include a linear radiolucency near the normal growth plate (double physeal line). Later in the course of the disease, there is periosteal reaction in the metaphyseal region. In severe cases, the physis may close prematurely as a result of the periosteal reaction, resulting in an angular limb deformity. CT examination may also be performed, but is usually not necessary unless radiographic signs are subtle.
Supportive care is important, based on clinical status. Fluid therapy may be indicated if dehydration is present. Feeding a large breed growth diet should be instituted. Analgesics may be needed. If noneseroidal anti-inflammatory medications are initiated, do not treat with steroids. Recent studies of Weimaraners with a presumed immune-mediate component have responded to corticosteroid treatment, but concurrent use of NSAIDs will likely result in gastrointestinal signs, and even gastric perforation. Range of motion of affected joints and cryotherapy applied to the area may be beneficial.
Breeds – Large and giant breeds
Gender – No apparent predilection
Age – Median age is 7 years, but cases may also occur between 18-24 months of age
Etiology – Unknown, but may have a genetic basis
Progressive lameness that may progress to severe lameness with development of a pathologic fracture, owners may notice swelling of the affected area, weight loss, and poor appetite in later stages of the condition.
Mild to moderate lameness, swelling of proximal tibia, pain on palpation, possible crepitus and instability if a pathologic fracture is present.
Radiographs of the crus and chest radiographs or CT for evaluation of metastatic disease. Fine needle aspirate or biopsy is recommended to confirm clinical suspicions.
Amputation with chemotherapy gives the best prognosis with a median survival time of approximately 1 year. Amputation alone gives palliative pain relief, but does not prolong survival. Other limbs and joints should be assessed to be certain that the dog can cope with an amputation. Limb sparing treatment may be an option in some early cases. Euthanasia is also an option.
Breeds – Any breed
Gender – No gender predilection
Age – Any age
Etiology – Trauma. Many cases occur as a result of automobile trauma. Because of this, careful evaluation of the thoracic and abdominal structures is important to detect any trauma to internal organs.
Often owners witness trauma, such as a fall, hit by automobile, or other sudden traumatic event that results in sudden onset of severe lameness.
Fractures of the crus result in pain on manipulation and crepitation during manipulation of the limb.
Radiographs are generally diagnostic, but CT evaluation may give additional details.
Most fractures of the crus require internal or external fixation to restore anatomy and function. Simple fractures in young dogs may be treated with a cast in some situations.