As a pet parent, it’s important not to ignore your dog limping. Of course, sometimes a sore muscle or other soft tissue injury can improve with rest. But, if the limping continues or is severe, it’s best to seek advice from your vet. A limp could indicate anything from a broken nail or splinter to a broken bone or even cancer. In this article, we’ll cover one of the most serious causes of limping, osteosarcoma in dogs. Read on to find out what it is, how to spot the signs that your dog’s affected, and how it’s treated.
Breeds commonly affected:
What is osteosarcoma in dogs?
Osteosarcoma is a type of malignant bone tumor that affects dogs. It is the most common bone tumor affecting dogs and is most common in large or giant breeds. These tumors are most commonly found at the end of the radius, at the carpal (wrist) joint, but they can also occur in the shoulder or knee. These tumors grow quickly, destroying the surrounding bone, and causing pain, swelling, and even pathological fractures. However, being malignant, osteosarcoma can also spread to cause metastatic tumors, commonly found in the lungs.
What are the symptoms of osteosarcoma in dogs?
The symptoms of osteosarcoma in dogs include:
Limping (which is often moderate to severe and doesn’t improve with standard pain relief or rest)
Swelling (in the affected area e.g., carpus, knee, shoulder)
How is osteosarcoma in dogs diagnosed?
Since osteosarcoma in dogs commonly causes quite severe lameness, pain, and swelling, your vet's physical examination will give some clues as to whether osteosarcoma is a potential cause of the symptoms. If your dog has suddenly started limping and the pain is severe, an X-ray will be needed to give more information. This will help to rule out other causes, like a fracture or cruciate ligament rupture. If osteosarcoma is the cause, the bone will look mottled or moth-eaten on the X-ray and there will be evidence of the swelling and inflammation. If the vet suspects osteosarcoma, they may recommend taking X-rays of the chest at this point, to check for metastatic spread to the lungs. Unfortunately, osteosarcoma cannot be diagnosed from X-rays alone, a bone biopsy is also needed to confirm the type of tumor.
What are the treatment options for osteosarcoma in dogs?
To treat osteosarcoma, the tumor must be removed, which usually involves amputating the affected leg, improving the dog’s pain levels. Unfortunately, though, because osteosarcoma spreads so quickly, just removing the tumor isn’t curative and the cancer will continue to progress via the secondary tumors. Chemotherapy alongside amputation will sometimes improve survival times but is unlikely to be curative. In dogs who don’t undergo amputation or chemotherapy, medications called bisphosphonates can slow the destruction of the bone, reducing the risk of pathological fractures and reducing pain.
What is the prognosis for osteosarcoma in dogs?
Without any treatment, the prognosis for osteosarcoma is very poor, due to extreme uncontrollable pain which usually affects quality of life and leads to the decision to euthanize reasonably soon after diagnosis. Sadly, no treatment is curative, so osteosarcoma is life-limiting, but with surgery and chemotherapy, dogs may live for around 6 to 12 months, depending on the location of the tumor.
Can osteosarcoma in dogs be prevented?
Unfortunately, osteosarcoma in dogs cannot be prevented. However, it is less common in smaller breed dogs.
Summary
Osteosarcoma is one of the most serious causes of acute limping or pain in dogs. Because it’s so painful and the bone is weakened by the tumor, it’s important to spot the signs early so that your vet can investigate, provide treatment, and get your dog’s pain under control.
About the Author
This blog was written by Dr. Hannah Godfrey, a veterinarian with years of experience treating diverse animal patients. Her expertise includes advanced training in canine and feline dentistry. Now, she focuses on empowering pet owners through informative writing. Read more about Dr. Godfrey's background here.
Hannah graduated from the Royal Veterinary College in 2011 and began work straight away at a busy mixed practice. Initially, she treated all species, but focused on small animals from 2014. She has a passion for soft tissue surgery, ultrasound, and canine and feline dentistry, having completed additional training in these areas.
In 2018, Hannah began working at a smaller, independent practice close to home, in order to devote more time to her other loves – writing comedy fiction and spending time with her young family. She now spreads herself across clinical and non-clinical veterinary roles, including working as a locum vet, being Community Lead for a team of Human Factors trainers, and using her writing skills to help educate and inform pet owners.
