Degenerative Joint Disease (DJD, Osteoarthritis)

Degenerative Joint Disease is a very common progressive condition, resulting from hip dysplasia, cruciate ligament injuries, fractures, joint trauma, obesity, overworking, among many causes. In short, DJD implies the deterioration of articular cartilage and the formation of new bone in less than optimal places. Articular cartilage is composed of collegan fibers linked together with proteoglycans (consisting of hyaluronic acid and glycosaminoglycans). Hyaluronic acid has multiple functions -- it binds proteoglygcans groups into larger aggregates, and it also is an important part of the synovial fluid which inhibits inflammatory cell activity and enzyme production by joint cells. The activity of these enzymes combined with damage from aging and injury causes a disruption of the collagen fibers and creates an ever-escalating inflammatory state in which immune cells secrete inflammatory proteins and the cartilage-producing cells fight a losing battle of synthesizing new proteoglycans while existing ones are destroyed.

When enough cartilage is lost, bone is exposed and it attempts to protect itself with new bone growth, resulting in jagged and irregular "spurs" which decrease the mobility of the joint and greatly increase the pain. Also, pieces of degrading cartilage can become dislodged and float free in the joint, becoming calcified after a time (which we call "joint mice").

Diagnosis of joint problems relies greatly on a thorough physical exam -- you will notice us observing your pet moving about to ascertain the pattern of lameness, which helps us clue in to the appropriate areas to examine. Then we thoroughly manipulate each possibly affected joint, searching for clues such as restricted range-of-motion, grinding, clicking, popping, pain, tensing of muscles, or excess movement in a certain direction (as with a ligament tear). In large dogs, we often will recommend continuing the exam under anesthesia, because of their size and muscle strength. This is an opportune time to take radiographs of the areas in question as well. Hip or shoulder or spinal x-rays in particular require anesthesia for proper positioning. Using our exam findings, combined with radiographs, we can most accurately give you a prognosis and prescribe medications or recommend surgery.

Treatment of certain joint problems requires surgery -- ruptured cruciate ligaments, for example, or miniscule elbow fractures. Severe advanced hip problems may not respond to any medical options and merit surgical intervention. Thankfully, the medicines available to us today have advanced beyond aspirin and cortisone. The two principle approaches to treatment are: controlling the inflammation and pain using "non-steroidal anti-inflammatory drugs" (NSAIDS), and supporting the repair and development of new articular cartilage using chondroprotective "nutraceuticals." Quite often we use both of these together. The newer drugs in the anti-inflammatory class include Rimadyl and Etogesic, both of which are far better and have fewer side effects than aspirin, phenylbutazone, ibuprofen, etc. but which are more expensive.

The chondroprotective supplements are all various combinations of "building blocks" for new articular cartilage-glycosaminoglycans, chondroitin sulfates, vitamin C, Perna cannaliculus mussel, brewer's yeast, shark cartilage, yucca, etc. The ones we have used, sometimes with great success, are Cosequin, Adequan, Synovi-MSM. These agents can help if the degenerative process is in an early enough stage to allow cartilage regeneration, and we expect results within 6 weeks of starting them.

Other aspects of treatment are very important and involve weight reduction, slow and consistent excercise, and good nutrition. Prognostically, the important thing to note is that degenerative joint problems are largely progressive and irreversible; our hope is to slow the progression and allow the most pain-free existence possible.

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