Osteoarthritis

Overview 

Arthritis, or osteoarthritis (OA), is a chronic and progressive joint disease that commonly affects dogs. This degenerative condition makes dogs lose their joint cartilage, leading to other changes in their bones and causing pain, inflammation and difficulty using the affected limb.  

OA is not just a disease that occurs in senior dogs and can develop at any age, especially in dogs with contributing factors, such as obesity or other orthopedic conditions.  

While there is no cure for OA, there are several strategies for slowing its progression, managing mobility and minimizing pain.  

Cause 

Joints normally contain both fluid and cartilage, which cushion the body from forces during movement — allowing smooth, fluid motion without the friction of rubbing on bone.  

With OA, joint fluid decreases and cartilage thins, reducing the joints’ shock-absorbing capability. As the cartilage progressively deteriorates, bony changes around the joint develop, causing more inflammation, pain, stiffness and difficulty using the joint. 

Many factors contribute to the development of OA. Often there is more than one cause, but in some cases, there may also be no obvious underlying cause. Several orthopedic diseases may lead to the development of OA by causing repetitive injury to the joint cartilage — including hip dysplasia, elbow dysplasia, patella luxation, cranial cruciate ligament damage, previous fractures, repetitive high-impact activities and more.  

Obesity contributes significantly to the development of OA due to the added force placed on joints. Fat cells also produce inflammatory mediators, which worsens the progression of OA.  

Clinical signs 

The signs of OA may vary from mild to severe based on the chronicity and number of joints affected. Signs may include any of the following:

  • Pain 

  • Stiffness 

  • Lameness or a change in gait  

  • Decrease in activity or reluctance to walk, run or exercise 

  • Difficulty navigating stairs or jumping on couches 

  • Difficulty getting up from lying down 

  • Muscle wasting 

  • Sudden changes in behavior, such as irritability or aggression 

Diagnosis 

OA is diagnosed after a physical exam, where your veterinarian will observe your dog's gait and posture, and feel for any abnormal changes to the joints or signs of pain.  

X-rays may be performed to further assess the joint or bony changes, and to help diagnose any underlying orthopedic conditions. 

In some cases, more advanced imaging may be performed to better evaluate the cartilage and other soft tissue structures surrounding the bone that do not show up on X-rays. To examine those areas, your veterinarian will schedule an arthroscopy, CT or MRI.  

Treatment 

The goal of treatment is to minimize pain, slow the progression of damage, and maintain or develop muscle mass. Treatment is achieved with a combination of therapies, which may include any of the following:  

  • Lifestyle changes:  

    • Weight control 

    • Low-impact activities, such as leash walks or swimming 

    • Use of non-slip rugs and ramps to get on beds, couches or cars  

  • Physical rehabilitation:  

    • Underwater treadmill 

    • Range of motion exercises or other therapeutic modalities — including acupuncture, LASER therapy and more  

  • Pain management:  

    • NSAIDs (nonsteroidal anti-inflammatory drugs) are commonly prescribed medications to manage OA pain and inflammation. Your dog will require routine monitoring with blood work if they require long-term NSAIDs.   

    • Additional medications, such as gabapentin and amantadine, may be given in combination with NSAIDs.

    • Librela (bedinvetmab) is a type of injectable medication known as a monoclonal antibody that can be given once monthly to provide longer-term control of OA pain. It targets a specific driver of OA pain called nerve growth factor (NGF).
  • Joint support:   

    • Supplements, such as glucosamine and chondroitin sulfate, and omega-3 fatty acids 

    • Joint injections, such as platelet-rich plasma, stem cell therapy or RSO (radiosynoviorthesis or brand name Synovetin OA) 

  • Surgery:  

    • May be recommended for some cases that have underlying causes of OA, such as hip dysplasia, cranial cruciate ligament rupture and elbow dysplasia, among others  

Outcome 

OA causes progressive damage to affected joints, and the prognosis varies depending on the underlying cause and severity. While there is no cure for OA, there are several ways to manage pain and delay its progression, allowing many dogs to live comfortably with a multimodal approach to treatment.  

The earlier OA is diagnosed and managed before the severe progression of OA, the better the long-term outcome.