Cartilage covers the end of bones. It is a smooth surface designed to enable gliding of two points (ends of bones) over each other. In osteoarthritis (also known as degenerative joint disease) it is the damage to the cartilage which impinges on the joint function. When the two bones can no longer slide over each other, there is pain.
Cartilage contains chondrblasts (cells), collagen (fibres) and proteoglycans (proteins) and is composed in such a way as to hold water. The more water is retained, the better the cushioning and gliding effect of cartilage. Below is a schematic representation of cartilage taken from Encyclopedia of Canine Nutrition Pibot P. Biourge V. and Elliott D. and printed by Royal Canin 2006.
Joint supplements are designed to maintain healthy cartilage. There is a balance between breaking down and regeneration of cartilage. When the destruction outweighs the creation of cartilage disease occurs. Joint supplements are designed to maintain the positive, healthy balance. These products are also referred to as Slow Acting, Disease-Modifying Osteoarthritic Agents. Formulations are usually oral and can be liquid, powder, pill/tablet/capsule or a dietary additive.
There is much variety in the components and any one of the following may be included in a joint supplement.
1. Glucosamine – an essential building block of the protein molecules (proteoglyans or glucosaminoglycans GAGs) found in the cartilage matrix. It stimulates the production of new cartilage and joint fluid.
2. Chondroitin Sulphate – is a GAG which is an important structural component of cartilage. It is able to withstand constant compression and concussion thereby reducing joint damage. It also has anti-inflammatory properties. The size of the molecule is important for optimal absorption. Biological chondroitin sulphate is preferable over that which is laboratory manufactured.
3. MethylSulphonylMethane MSM is a natural, organic bound sulphur occurring in almost every living thing. Its use in management of joint disease lies with the ‘sulphur’ component which is required for formation of healthy bones, joints, ligaments and tendons. There is now a large body of research which supports its anti-inflammatory properties.
4. Hyaluronic Acid is a normal constituent of the joint. This molecule binds a large quantity of extracellular water within the matrix and as such it helps to lubricate joints.
5. Green Lipped Mussel Extract GLME is an excellent source of natural glucosamine and chondroitin sulphate. It also has vitamins and omega 3 fatty acids.In a study conducted by Pollard B. et al “GLME had a beneficial effect on the clinical signs of dogs presumptively diagnosed with mild-to-moderate DJD. Long term therapy may be required before improvement is apparent.”
6. Omega 3 Fatty Acids A powerful anti-inflammatory which reduces stiffness and pain.
7. Vitamins C and E are powerful antioxidants and immune boosters. The body is constantly producing free radicals and its own antioxidants to counteract their damaging effects. The body does not produce sufficient antioxidants to negate the free radicals produced and therefore, antioxidants must be supplemented. Health is about balance. Free radicals damage healthy cells making the cells vulnerable to disease. Antioxidants bind with free radicals thereby making them harmless to the body.
8. Manganese is important for joint integrity as well as cartilage and bone growth.
Not every product will contain every component. The first two form the mainstay of any joint supplement and need to be of a high quality. Thereafter, your main concern should be what your dog finds more palatable or easier to consume? For some a pill is easier to administer than a liquid. If one supplement does not seem to be having an effect, try another before concluding that it does not work. Finally, it takes 6 to 8 weeks before all the benefits of these supplements can be seen so you need to commit to the long run with the use of these products.
Author: Dr. Tanya Grantham. B.Sc (Hons) BVSc CertSCVA; Certified Canine Rehabilitation Practitioner CCRP - Animal Health and Hydro