What is arthritis ?
Arthritis (osteoarthritis) is a progressive deterioration of cartilage in the joints between two or more bones. Many immature dogs develop arthritis due to hereditary or developmental disorders such as osteochondrosis, elbow dysplasia or hip dysplasia. Trauma-induced arthritis can occur at any age. Primary arthritis is thought to be due to long-term exercise combined with aging. Working dogs, athletic dogs and obese animals place more stress on their joints, and are thus more likely to incur injury and arthritis. Occasionally infectious, cancerous or immune-mediated diseases can cause arthritis.
Dogs suffering from arthritis often show intermittent lameness that slowly becomes more severe and frequent with time. Signs may appear worse after exercise, long periods of lying down, or weather changes. Some dogs will appear to walk 'stiffly' rather than with a limp.
Arthritis is diagnosed by radiographic (x-ray) examination of affected joints. X-rays normally involve a general anaesthetic to allow correct placement of the limbs to give an image of the best diagnostic value. Often, in our geriatric patients, the clinical signs of arthritis are enough.
If you are embarking on conservative management of a ruptured cruciate ligament for your animal then the same applies as for arthritis.
Treatment
Treatment of arthritis may include medical or surgical options (such as knee reconstruction). Most patients are initially treated medically. In young animals (less than 12 months) specialised orthopaedic procedures may be performed to correct and joint or bone abnormalities which may result in arthritis later in life.
Cartilage in joints is composed of a mix of 'proteoglycans' and other substances. Inflammation of joint due to stresses and strains leads to excessive destruction of these 'proteoglycans' or a reduction in their formation. The aim of medical treatment is to limit joint inflammation.
Non-steroidal Anti-Inflammatory Drugs
A wide variety of non-steroidal anti-inflammatory drugs can be used limit the production of joint-damaging substances. At this clinic we use Rimadyl, Metacam, Previcox or Tolfedine. These drugs are excellent in relieving acute pain associated with arthritis. Unfortunately there are some side effects related to long-term use of these drugs. Side effects include kidney or liver damage, or stomach ulcers. It's for this reason that we may only prescribe these drugs for a short period at initial diagnosis or during severe bouts of arthritis. The vet will prescribe the most appropriate drug at the correct dose for your pet.
Chondroprotective Drugs
"Cartilage protective drugs", such as Cartrophen not only inhibit inflammation within joints (and therefore destruction of cartilage) but also stimulate the activity of the cells lining the joints. Stimulation of these cells results in an increased production of the substances which form joint cartilage. Cartrophen is not only recommended to arthritic dogs, but also to those who have recently undergone joint surgery (such as cruciate ligament repair). There are no known significant side-effects to date. Treatment involves 4 once weekly injections (a four-week course) and then a follow-up "booster" every 6-8 weeks. Another form of the drug - Sylet - has been released that is given weekly after the initial course of injections and saves returning to the surgery.
Over-the-counter Preparations
A warning: 1440 people on a double trial showed no benefit to these preparations.
Nutritional supplements or preparations containing glucosamine hydrochloride and chondroitin sulphate (available from us as "Sasha's blend" or from healthfood stores) act as "cartilage support". Used daily these supplements are reported to provide ongoing cartilage repair, protection, and pain relief. Different strengths are available but as a guide, if you use a preparation containing 500mg glucosamine + 500mg chondroitin per tablet a 10-20kg dog should get 2 tablets per day ( 1 morning + night), a 20-40kg dog 3 tablets per day (2 morning + 1 night), and a dog over 45kg should get 4 tablets per day (2 morning and 2 night). Some preparations come as a powder rather than a tablet, some owners find this good to mix with wet food. The aim is to gradually reduce the dosage as the signs of arthritis decrease over time. Obviously, if you have any questions don't hesistate to contact us on 03 9415 8288 Voip 03 90188911 mobile 0417 654 415 or Animal Accident Emergency 03 9379 0700.
Written Dr Louise Jones 2003, modified Dr Bill Ryan 2008