Osteoarthritis in Dogs

Key Takeaways

Arthritis is a general term referring to damage and inflammation of joints. Osteoarthritis (OA) in dogs is a chronic, progressive form of this disease resulting in pain and reduced mobility.

• Risk factors for osteoarthritis include traumatic injury to the joint, genetic joint disease, excessive exercise, and obesity

• Dogs with OA present with signs of reduced mobility including lameness, stiffness, and reduced exercise tolerance

• Some dogs exhibit behavioral changes such as irritability with other dogs or people, and not wanting to be touched

• Physical examination localizes pain, then OA is diagnosed with imaging of the affected joint(s)

• Treatment of OA normally begins with lifestyle changes such as weight loss and exercise management

• As OA progresses, medication is used to reduce pain and improve mobility

• Surgical options are available for some conditions

• OA is not curable, but can be managed effectively, reducing pain and slowing deterioration

A Closer Look: What is Osteoarthritis in Dogs?

Dogs experiencing pain from osteoarthritis may develop behavioral changes such as aggression, irritability, or not wanting to be touched. Dogs may lash out or whimper with movement or manipulation of the affected joint. Rarely, OA affects the joints of the jaw bone (temporomandibular joint) resulting in oral pain, reduced appetite, and reduction in size of the facial muscles.  Osteoarthritis affecting the spine can interfere with the spinal cord, causing a wobbly, uncoordinated gait (ataxia). 

While not life-threatening as a stand-alone condition, OA is potentially debilitating and is cited as the cause of euthanasia in 40% of dogs that have been diagnosed with the condition. OA is a progressive condition but patient quality of life is significantly improved with treatment. Dogs showing signs of osteoarthritis benefit from prompt veterinary assessment so treatment can begin.

Risk Factors

Arthritis can be categorized according to what is believed to be the trigger of the inflammation. Trigger factors for OA are:

• Normal loading of an abnormal joint such as in genetic joint disease, or prior trauma involving single or multiple joints

• Abnormal loading of a normal joint, such as in obesity, or excessive exercise • Traumatic injury to a joint

Conditions associated with normal loading of an abnormal joint are typically seen in younger dogs, as the abnormal joint structures tend to fail earlier on in life. Conversely, abnormal loading of a normal joint typically occurs in older dogs, particularly senior dogs over the age of 8. In these conditions, the joint is continuously subjected to small amounts of damage, which eventually accumulates into osteoarthritic change. Traumatic injury to a joint can occur at any age, and leads to osteoarthritis through both disrupting normal joint function and causing damage that accumulates over time.

Possible Causes

Arthritis is a generic term which describes inflammation of the joint. Osteoarthritis is the degenerative form of this condition and is distinct from septic or immune- mediated arthritis. In osteoarthritis, the joint cartilage and bone is worn down over time, and often shows progressive symptoms. Osteoarthritis is linked to any or all of the following triggers: genetic predisposition, injury, and lifestyle factors (weight and level of exercise).

Main Symptoms

OA is a progressive condition and symptoms vary depending on the extent of the disease. The main symptoms include:

• Lameness • Limited mobility • Exercise intolerance • Changes in gait such as “bunny-hopping” • Muscle loss

Testing and Diagnosis

The main diagnostic tests used to identify osteoarthritis are:

• Physical examination • Imaging, including X-rays, CT/MRI scan, and arthroscopy

• Arthrocentesis (sampling fluid from the painful joint)

Physical examination is sufficient to detect pain, but OA must be differentiated from alternative types of arthritis or other joint disease. 

Treatment of OA focuses on alleviating symptoms, as there is no cure for osteoarthritis. Initial management strategies are used  to improve mobility, reduce pain, and slow progression. These strategies include:

• Exercise management • Weight loss • Physio/hydrotherapy • Massage • Acupuncture/acupressure/electroacupuncture

• Low level laser therapy • Nutraceuticals

If necessary, medications to treat pain and reduce joint inflammation can be added, such as:

• Antiinflammatory drugs • Monoclonal antibody therapy • Joint injections • Other pain relieving medications 

Surgical procedures for many types of osteoarthritis are also available, and help improve joint stability and slow down deterioration. Surgical interventions include:

• Improvement of joint stability following trauma or degeneration • Removal (arthroplasty) or replacement of diseased joints

• Amputation (in severe, end stage joints)

Steps to Recovery

OA is a progressive condition which cannot be cured. Mild cases of OA, particularly those diagnosed later in life, may not significantly impact quality of life or require treatment. Severe, early onset cases of OA require intensive treatment and often have a significant impact on mobility and quality of life. Most dogs with OA respond to treatment and experience reduced pain and improved mobility and/or demeanor.

Prevention

Breeding programs attempt to reduce the incidence of genetic joint disease. It is good practice to buy dogs from reputable breeders who perform health testing, particularly in breeds predisposed to developing joint problems.

OA can be prevented or slowed by maintaining a healthy body condition. Increased body weight puts additional strain on the joint tissues, eventually causing early degeneration. Fat cells also produce chemicals which exacerbate OA and joint pain. Studies have shown that dogs fed a calorie-restricted diet live 15% longer and experience OA later in life.

Excessive wear and tear on the joints through high levels of exercise is a trigger for OA. Limited evidence exists to recommend specific exercise limits, but it is sensible to limit intense, repetitive exercise (such as retrieving a ball) as much as possible.

Is Osteoarthritis Common in Dogs?

OA is common, diagnosed in 20% of dogs.

Typical Treatment

• Medication • Surgery • Complementary therapy, including

◦ Exercise management ◦ Weight loss ◦ Physio/hydrotherapy ◦ Massage ◦ Acupuncture/acupressure/electroacupuncture ◦ Low level laser therapy ◦ Nutraceuticals