Issue Description Hypertrophic osteopathy is a severely
debilitating disease which occurs secondary to other diseases. The
primary disease is usually a cancer, but occasionally others e.g.
infectious diseases such as tuberculosis, and most often they involve
the lungs or are disease processes lying within the chest. Affected
animals develop bilateral, symmetrical soft tissue swelling of the
lower legs with periosteal new bone formation. These bony changes do
not involve the joints or joint capsule. Other Names HO
Causes Although it has been theorized that
hypertrophic osteopathy may be caused by toxins, nerve signal
malfunctioning, or poorly oxygenated blood reaching your dog's
skeletal structure, it is not definitively known what causes
All dog breeds can suffer from Hypertrophic osteopathy, but it is more
common in large breeds. Based on case reports, the Boxer dog have a
higher risk of developing Hypertrophic osteopathy compared to other
breeds. This is probably caused by the higher occurrence of primary
lung cancer and bone cancer in this breed. The German Shepherd also
has an elevated risk of developing Hypertrophic osteopathy.
Hypertrophic osteopathy is more common in female dogs than in male
dogs. This is probably related to the fact that mammary carcinomas can
lead to Hypertrophic osteopathy.
When small and medium
sized dogs get Hypertrophic osteopathy, they are usually middle aged
or older, since cancers are less common in young dogs. Large and giant
dog breeds are however prone to developing bone cancers while still
fairly young and vets are therefore quite frequently presented with
young, large dogs with Hypertrophic osteopathy.
Reluctance to move.
Lameness in one or more legs.
Legs that are enlarged and firm to the touch.
Swelling of the toes extending to the level of the elbow & stifle
Diagnosis Your veterinarian may suspect hypertrophic
osteopathy after examining your pet, but will probably perform several
tests to confirm the diagnosis and to identify the underlying cause.
Hypertrophic osteopathy is an indicator of another disease process;
therefore, it is important to understand the need for further
diagnostic tests to identify the primary cause. Radiographs (X-rays)
of the affected bones generally show characteristic changes for this
condition. Radiographs of the chest and abdomen, and an ultrasound
study of the abdomen are often performed to look for the underlying
cause of the HO condition. Blood tests are performed to assess the
general health of your pet and to look for organ dysfunction that may
point to an underlying cause.
Treatment The treatment for hypertrophic osteopathy is to
identify, and in most instances surgically remove the underlying mass
(tumor). The type and extent of surgery required depends on the
Prognosis Removal of the inciting cause may or may not
bring about regression of clinical signs. Lameness and limb
disfigurement due to bony changes may take several months to regress,
if at all. The prognosis for animals with HO is generally guarded to
poor due to the frequent recurrence of the tumors.