Panosteitis

Panosteitis is a painful bone condition of large breed dogs typically between 5 and 18 months of age. This can be thought of as canine “growing pains”. While this is quite painful when flare-ups occur it usually resolves permanently as the dog matures. The cause of panosteitis is not clear. Large breed male dogs are more likely to develop panosteitis, however smaller dogs as well as female dogs can develop it. German Shepherds, Golden Retrievers, Basset Hounds, Doberman Pinschers, and Labrador Retrievers are predisposed to panosteitis.

SIgns of panosteitis are lameness that shifts from limb to limb and is often accompanied by a fever.  Episodes can last 2 to 5 weeks and will recur until the puppy outgrows the condition. Some dogs may have a relapse around 2 years of age, but symptoms generally resolve on their own.

Diagnosis of panosteitis is based off of history as well as being a large breed male puppy with the above listed symptoms. Other problems that must be ruled out are hypertrophic osteodystrophy and osteochondritis dissecans. On a physical exam the doctor will look for signs of pain when the limbs of the dog are touched. On x rays there will be a tell tale cloudiness to the bone marrow cavities of the bones of the limbs. 

The cause of panosteitis is rather complicated.  The bone marrow cavity contains 2 types of marrow: marrow that makes blood cells and marrow that is fat. In cases of panosteitis the fatty marrow is replaced with fibrous tissue, the fibrous tissue is then replaced by a type of bone called woven bone. Woven bone is characterized by haphazard growth and is what causes the cloudy appearance on x-rays. This woven bone can fill up the entire marrow space. Eventually normal bone cells dissolve the woven bone and the bone tissue returns to normal.

It is currently unknown what may cause this remodeling of the bone marrow cavity to occur. 

Pain relief and time are the treatment for panosteitis. For the majority of patients this means administration of non-steroidal anti-inflammatory medications such as Rimadyl. If this is not helping the pain enough there are other pain control options that may be added.