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Pain Management: Other options

Chondroprotective Agents

The expanding knowledge of articular cartilage biochemistry and pathogenesis of osteoarthritis has focused research on slowing the progression of degeneration and promoting cartilage matrix synthesis. This research has identified substances, termed chondroprotective agents, which counter the arthritic degenerative processes and encourage normalisation of the synovial fluid and cartilage matrix. Chondroprotective agents are compounds that stimulate chondrocyte synthesis of collagen and proteoglycans, as well as synoviocyte production of hyaluronan, inhibit cartilage degradation and prevent fibrin formation in the subchondral and synovial vasculature. Examples of compounds that exhibit some of these characteristics are the endogenous molecules of articular cartilage, including Hyaluronic Acid, Glucosamine and Chondroitin Sulphate.

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Glucosamine and Chondroitin Sulphate (Matrix Enhancement Therapy)

Numerous studies have demonstrated that glucosamine stimulates the synthesis of proteoglycans and collagen by chondrocytes. Since osteoarthritis (OA) results when cartilage breakdown exceeds the chondrocytes' synthetic capacity, providing exogenous glucosamine increases matrix production and seems likely to alter the natural history of OA. Glucosamine also has a mild antiinflammatory activity that is unrelated to prostaglandin metabolism. In randomised, double-blinded, placebo-controlled clinical trials using oral preparations, glucosamine salts have been verified as efficacious in the management of OA, and have not demonstrated any toxicity, severe side-effects, or abnormal clinical, biochemical, or haematological changes. Chondroitin sulphate is the most abundant glycosaminoglycan in articular cartilage. It plays an important structural role in articular cartilage, notable for its role in binding with collagen fibrils. As a chondroprotective agent, it has a metabolic effect as well: its action is to competitively inhibit many of the degradative enzymes that break down the cartilage matrix and synovial fluid in OA. Because of the additional mechanism of action is via the prevention of fibrin thrombi in synovial or subchondral microvasculature, chondroitin sulphate has been investigated for its anti-atherosclerotic effect. When used together, it seems that glucosamine and chondroitin sulphate combine effects to stimulate the metabolism of chondrocytes and synoviocytes, inhibit degradative enzymes, and reduce fibrin thrombi in peri-articular microvasculature. Numerous clinical studies performed on horses at US veterinary schools have supported this combination and synergistic effect.

There is a growing body of evidence for the efficacy of glucosamine in symptom modification, and, given the low level of adverse side effects noted from these products and the relatively low cost, it may be reasonable for some patients with knee osteoarthritis to try taking glucosamine. It should be noted, however, that a very recent review co-authored by a senior and highly respected academic rheumatologist in the UK concluded "there is more confusion and hype than magic about glucosamine". The authors cautioned against its wholesale use and recommended the need for "further large clinical trials without company interference". Human randomised, double-blind clinical trials are currently underway.

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With increased understanding of the pathogenesis of osteoarthritis new therapies are being developed, one of which is viscosupplementation with hyaluronic acid. Viscosupplementation is the term for a therapy that aims to be chondroprotective by restoring the fluid properties of the tissue matrix in osteoarthritis sufferers by means of intra-articular injections if highly purified viscoelastic solutions of sodium hyaluronate (HA, also known as hyaluronan). The use of viscosupplementation is based on the observation that there is a decrease in viscosity and elasticity of the synovial fluid in osteoarthritis and that the native hyaluronic acid in osteoarthritic knees has a lower molecular weight than of that found in normal healthy knees. Replenishing the hyaluronic acid component of normal synovial fluid may play a role in supplementing the elastic and viscous properties of synovial fluid, which may help relieve the signs and symptoms related to osteoarthritis and improve function. Intraarticular injections of hyaluronic acid (HA) are widely used in the Asian and European orthopaedic communities for controlling the pain and loss of joint function resulting from osteoarthritis. In more than 10 years, it has been used in approximately one million patients in 20 countries, with an excellent safety record. Treatment comprises of three weekly intraarticular injections. HA is well tolerated with no demonstrable toxicity and only a few side effects (transient injection site pain and swelling). The new generation of bio-fermented hyaluronic acid is exceptionally pure and contains no animal protein and no residual cross linking reagents. This is the purest and closest product to the naturally occurring substance.

The injectable substance is hyaluronate, a naturally occurring viscoelastic agent that supposedly acts as a shock absorber and lubricant in the knee joint. Preliminary results of animal studies demonstrate that intraarticular injection of hyaluronic acid may have protective effects on articular cartilage. Because it is injected directly into the joint, the onset of action is fairly rapid. Possible mechanisms by which HA may act therapeutically include: providing additional lubrication of the synovial membrane, and controlling permeability of the synovial membrane, thereby controlling effusions. Other possible, though less certain, mechanisms include: promotion of cartilage matrix synthesis and reaggregation of preoteoglycans. However, the exact mechanisms of action, articular cartilage changes and short and long term results remain unknown.

In recent years, the concept of viscosupplementation has gained widespread acceptance in the USA and Europe, and to a limited extent in the UK, as a new treatment for the pain management in OA of the knee. There is no doubt that viscosupplementation represents valuable addition to current treatments for osteoarthritis and an alternative treatment, especially when other forms of treatment have failed.

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Weight Management

Because your weight can have an effect on your knee pain, the body mass index calculator can help you where you are in terms of appropriate weight for your height. The body mass index (BMI) has been the medical standard for obesity measurement since the early 1980s.

To calculate your body mass index click on this link:

Over the years, slimming has become big business. There have been many slimming crazes which may have left you confused about the best way to loose weight. Unfortunately there is no miracle cure. ' Crash' diets are usually unbalanced and designed to be used for only a few weeks. Although some can be effective in the short run, most people find that they put weight back on as soon as they return to normal eating. The only way to lose weight permanently is to change your eating habits. Realistically you can expect to lose about 1lb (1/2kg) per week, which is safe and sensible rate of weight loss. Do at least 30 minutes of exercise, like brisk walking, most days of the week. The idea is to use up more calories than you eat. You need to use up the day's calories and some of the calories stored in your body fat.

For a guide on losing weight visit this UK web site:

Free Weightloss Booklet: t o order this excellent and helpful free colour booklet So you want to lose weight...for good from the British Heart Foundation click on this link:

Site last updated on: 28 March 2014

Disclaimer: This website is a source of information and education resource for health professionals and individuals with knee problems. Neither Chester Knee Clinic nor Vladimir Bobic make any warranties or guarantees that the information contained herein is accurate or complete, and are not responsible for any errors or omissions therein, or for the results obtained from the use of such information. Users of this information are encouraged to confirm the accuracy and applicability thereof with other sources. Not all knee conditions and treatment modalities are described on this website. The opinions and methods of diagnosis and treatment change inevitably and rapidly as new information becomes available, and therefore the information in this website does not necessarily represent the most current thoughts or methods. The content of this website is provided for information only and is not intended to be used for diagnosis or treatment or as a substitute for consultation with your own doctor or a specialist. Email addresses supplied are provided for basic enquiries and should not be used for urgent or emergency requests, treatment of any knee injuries or conditions or to transmit confidential or medical information. If you have sustained a knee injury or have a medical condition, you should promptly seek appropriate medical advice from your local doctor. Any opinions or information, unless otherwise stated, are those of Vladimir Bobic, and in no way claim to represent the views of any other medical professionals or institutions, including Nuffield Health and Spire Hospitals. Chester Knee Clinic will not be liable for any direct, indirect, consequential, special, exemplary, or other damages, loss or injury to persons which may occur by the user's reliance on any statements, information or advice contained in this website. Chester Knee Clinic is not responsible for the content of external websites.

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