OSTEOARTHRITIS – DEGENERATIVE JOINT DISEASE

Osteoarthritis, abbreviated as OA, affects approximately 25% of dogs.  These dogs experience either a loss of the cartilage that is found between joints or damage to this cartilage.  Normally this cartilage protects the bones whilst movement or bending takes place. Essentially it is a cushioning between two bones which prevents the bones from directly rubbing against each other during movement of joints. OA can be seen as a chronic condition which occurs because of other conditions which the dog has prior to the development of OA.  The first of these conditions is the growth of osteophytes, which involves abnormal growth of bone in the affected joint.  Obviously, any additional bone pieces within the joint will limit the space between the bones and cause unnecessary friction.

Unlike in humans who have OA, dogs who suffer from OA usually present with disease of the bones like dysplasia of the hips, stifle joints or elbows as well as disease of cranial cruciate ligament, thus causing OA to develop as a secondary condition.  In older dogs, OA that is present and has no known cause is called idiopathic, meaning that the condition arose spontaneously with no direct recognizable reason.   OA can also occur in the smaller joints like the toe joints.  The medical name for this is pes, and manus.  Whether a dog is predisposed to OA is determined by factors like the age of the dog, whether the dog is overweight, gender, genetics, as well as their diet.

Symptoms indicating OA are not specific and can be confused with other health problems that the dog may have.  However, in determining that the dog needs to be seen by a veterinarian, one may observe that the dog becomes less active and is unwilling to exercise.  This will occur due to pain which will naturally prevent them from wanting to move.  Other signs that the dog has OA include being stiff, lame or not being able to jump.  The dog may walk differently or hobble and limp, as a way of minimizing pain by changing their body movements.  The animal might become aggressive or be uncomfortable due to pain that it is experiencing.  Generally, pain will cause changes in the behaviour of an animal and is one of the first signs that something is wrong.

Physical examinations and radiography are used to diagnose OA and your veterinarian will order certain diagnostic tests.  Initially, on first visiting, the examination will involve feeling the joints to see if the dog responds in a manner proving that they are experiencing pain.  Any abnormal thickness of joints, or evidence of fluid within the joints will be evident and be able to be felt by the veterinarian who is examining your pet.  Osteophytes (additional pieces of bone within the joint due to bones rubbing on each other) or loss of muscle will be able to be felt as abnormalities within the joints as well.

More accurate diagnosis will be needed by means of certain tests. Radiography as a form of obtaining images is most used and possibly the least costly method.  However, due to the fact that it is limited to only highlighting osteophytes or changes in the bone, while giving a sparse picture of the soft tissue, more complete imaging methods are recommended.  Radiographs can be used in conjunction with examinations of a physical nature and the use of magnetic resonance imaging or MRI scans.  These and computed tomography (CT) are becoming a popular choice due to the fact that these tools are better when analysing structures of the soft tissue or changes to the bone joints, giving a more complete view of the anatomical structure of tarsi (ankles), elbows and carpi (wrists).

The recommended therapy for osteoarthritis encompasses many aspects and varying approaches might be recommended.  Some of these are more conservative, while others will involve performing surgery.  Occasionally both options are used.  Each patient will be assessed and receive their customized treatment program, which is set up in consultation with the owner and the veterinarian who will be treating the animal.   Common conservative treatments, include the use of anti-inflammatory drugs of a non-steroidal nature. Examples of these drugs are meloxicam, carprofen, ketoprofen and deracoxib.  Another form of medication known as adjunctive pain controllers include corticosteroids, gabapentin, amantadine, codeine, tramadol, or acetaminophen.  There is, however, a lack of research pertaining to the effectiveness of these drugs.  Your veterinarian may also prescribe glucosamine sulphate, chondroitin sulphate, or omega-3-fatty-acid supplements to aid the joints and allow for a more comfortable journey for your pet.

Another treatment option is an injection into the joint using corticosteroids, hyaluronic acid or plasma which is rich in platelets. Over and above this, controlling your dog’s weight is important as obesity can put extra strain on joints exasperating the OA and making the animal less mobile.  You might need to change the activities that your dog participates in. Activities that are strenuous on joints, like going for a run or performing jumps, can cause the joints to become more inflamed.  Replacing these activities with walking on a leash, or less strenuous play, will allow your dog to exercise and maintain joint movement which will eventually improve the stability of the affected joints, but at a pace which is less stressful on their joints yet still effective in staying fit.  Surgery is also an option and might be considered in cases where the ligament of the animal has torn.  The surgery will include fusion of the joints (arthrodesis), or the joints will be completely replaced.  This is usually the case when hips or elbows are compromised.  Minor joints are more commonly stabilised by using stiches. This is usually performed on joints like the stifle (ankle joint).  Osteotomy methods, which involve bone grafts can also be used.

OA is one of those disease that progresses or worsens over time. An approach that is more conservative could be used to reduce the progressive nature and ensure a comfortable life for the animal.  Should surgery be the treatment of choice, recovery is normally good, particularly in cases where complete joints have been replaced, since this requires complete removal of the compromised joint.