Arthritis and NonSurgical Management of Arthritis

Frequently asked questions:

What is arthritis?
What is cartilage?
What is known about the cause of osteoarthritis?
How can I tell if my pet has arthritis?
What can I do to treat the symptoms of arthritis nonsurgically?
What are the treatment options if I’ve tried non-surgical therapies for 2 or more months with no real improvement?

What is arthritis?
Arthritis (also referred to as osteoarthritis or degenerative joint disease by veterinary professionals) is an inflammatory process of bone and cartilage and is a progressive, self-perpetuating, and destructive disorder that affects weight-bearing joints.

Understanding the nature of cartilage:
Cartilage is a cross-linked fibrous network of specialized proteins (collagens and proteoglycans), polysaccharides and water that serves to distribute pressure and to cushion the joint, allowing for relative movement of opposing bone surfaces with minimal friction and wear.  The cartilage that is found within the weight-bearing joints does not have the capacity to repair itself, as it does not contain nerve cells or blood circulation.  If the cartilage is injured or diseased, it cannot heal the same way muscle or skin can. 

What is known about the cause of osteoarthritis?
The exact cause is unknown, but many factors contribute to its initiation, perpetuation and pathogenesis.  As osteoarthritis progresses, there are changes that occur in all of the tissues of the joint.  There is controversy as to which event occurs first, changes in articular cartilage that lead to changes in subchondral bone or changes in subchondral bone that lead to changes in articular cartilage.

Older animals commonly get arthritis, but it is not a natural consequence of aging. Evidence for this is demonstrated two-fold: 1) not all older animals develop arthritis, and 2) osteoarthritis often results following a traumatic injury such as a bone fracture or ligament rupture in younger animals with normal, healthy joints.

The onset of arthritis is thought to occur by one of two generalized processes: abnormal stresses on normal cartilage (injuries, developmental defects) or normal stresses on abnormal cartilage (aging, other disease processes). In either case, the end result is a morphologic breakdown of articular cartilage by processes that are briefly generalized below.

Alterations in the cartilage matrix.  As arthritis progresses, there are changes in the cartilage structure itself.  These changes are not believed to cause arthritis, but occur because of the progression of the disease. 

Alterations in cellular activity.  Chondrocytes are the cells found within cartilage that manufacture, secrete and maintain the extracellular matrix.  The metabolic activity of the chondrocytes found within normal cartilage differs from those found in arthritic cartilage – changes in osmotic pressure and the balance of matrix components are noted.  What we are still trying to understand if these changes cause the disease or if they are a result of the disease. 

Alterations in subchondral bone.  The part of the long bone just under the cartilage becomes progressively thicker and denser – resulting in its lessened ability to deform and absorb forces applied to it.

Alterations in joint capsule and synovial membrane.  The joint capsule thickens and the synovial membrane becomes inflamed, resulting in loss of range of motion of joint and increased pain.

Alterations in periarticular bones. The bones around the joint affected with osteoarthritis may develop bony spurs in the joint or at the point of insertion of tendons and/or ligaments. These can develop quickly after a joint becomes injured, possibly in an attempt to increase the stability of the joint.

How can I tell if my pet has arthritis?
There are several signs that your pet may have arthritis, but for a diagnosis and treatment plan, you should make an appointment with your veterinarian.

Signs you can look for include:

• Older age; although arthritis is also common in young dogs with developmental conditions.
• Lameness, reluctance to go on long walks, use stairs or jump or change in gait.
• Stiff when the pet stands up, but becomes less lame upon “warming up”.
• “Weekend warrior” – stiff or painful after greatly increased bouts of activity.

Additional indicators your veterinarian may use to diagnose osteoarthritis:

            Physical Exam:

• Mild, slowly progressive muscle atrophy in affected limb (due to less use).
• Enlarged joints from thickened joint capsule or joint effusion.
• Painful joints with decreased range of motion.
• Grating joints in advanced cases.

            Lab Work:

• Synovial fluid can be tested for various biochemical indicators of arthritis but results are generally nonspecific to the origin of the disease.

            Radiography:

• X-rays can assist the veterinarian by providing evidence for thickened joints, narrowed joint space, osteophyte (bone spurs) formation, and joint effusion (an excess of fluid in the joint).

What can I do to treat the symptoms of arthritis?
The goal is to alleviate pain and discomfort, slow the degenerative process, and improve range of motion.  There are a number of non-surgical management therapies, described below, that can alleviate your pet’s painful symptoms.

Weight Management.  Getting the dog down to its recommended weight and keeping it there IS the most important thing an owner can do for their dog.  Studies have shown improvement in limb function from weight loss alone.  In addition, the prevalence and severity of osteoarthritis is decreased if dogs have a normal body condition.  Any therapy employed to treat arthritis will work better if the dog is not overweight.  Your veterinarian can help you determine the ideal weight for your dog.

Rest.  In the event of a painful flare-up, a few days of rest will allow for a decrease in the inflammation and increased mobility. 

Exercise.  Controlled daily activity is important for dogs with arthritis.  The goal is to maintain muscle mass and tone without burdening the joints. Swimming is a great low-impact activity that still allows for good range of motion, in particular it increases joint flexion when compared to land-based activities.  Initially, activity should be  restricted to walks on a leash that will increase in distance and frequency as the clinical signs subside.  A short daily walk is better than a just going for a longer walk on the weekends, which may lead to lameness and a dog unwilling to move in the following days. 

Alleviating the pain from daily actions.  Suggested ways to make your arthritic dog more comfortable include providing an orthopedic foam bed in a warm location, placing ramps as an alternative to stairs (especially going outside), elevating food and water bowls for large breed dogs, placing carpet runners on slippery surfaces such as tile or hardwood floors, a gentle massage on the affected area, and physical therapy as demonstrated by your veterinarian.

Medications. 

• NSAIDs (non-steroidal anti-inflammatory drugs) are generally effective at alleviating some of the discomfort.  While many drugs can be consider we would suggest you discuss the topic of using prescription NSAIDs with your veterinarian.  Please remember that there can be side effects with the use of these medications and you need to consult your veterinarian before administering them to your pet.
  
• Adequan (polysuflated glycosaminoglycan) is given by intra-muscular injection and has mixed results.  Some data suggests that it can slow the degenerative process may get incorporated into the cartilage matrix and inhibit degradative enzymatic processes while possibly stimulating cartilage component production. However, in dogs with established OA it seems to much less effective.

Supplements and Nutraceuticals:

• Essential fatty acids (Omega-3 oils such as fish oil or flaxseed oil). There is reasonably strong scientific evidence that these supplements can be beneficial for the prevention and treatment of OA.  To date, the best scientific evidence supports the use of prescription dog foods that have high concentrations of fatty acids. They can also be found as an over-the-counter nutritional supplement in most retail stores.
  
• Glucosamine sulfate /chondroitin sulfate.  There is very mixed scientific evidence regarding the use of these supplements for the treatment of OA and essentially no data supporting their use in dogs.  We remain skeptical about there efficacy and suggest that you carefully consider this controversy and their related expense when deciding if you want to use these supplements.

Please consult with your veterinarian to assess your pet’s medical and therapeutic needs before initiating any type of treatment.  What works for one dog may not work for another.  Work closely with your veterinarian and watch your dog closely so that between you and your veterinarian you can create the ideal medical management plan. 

What are the treatment options if I’ve tried non-surgical therapies for 2 or more months with no real improvement?
There are many different surgeries that may help relieve pain and increase joint mobility – but these surgeries are only considered for animals that are non-responsive to medical management.  All surgeries of this nature remove the joint surface and work one of three ways:

• Arthrodesis (fusion of the joint).  Eliminates the motion of the joint, but removes the pain.
  
• Excision Arthroplasty (removal the joint). Femoral head ostectomy (FHO) and radial head excision are examples. 
  
• Joint Replacement (artificial joints).  Available for hips, knees, and elbows. In animals, hip surgery is widely available, while knee surgery is less widely available, and elbow surgery is available only at the University of Minnesota.  Learn more about these options by clicking here.