Inflammation is the body’s normal protective response to an injury or illness and is a process that brings about repair. White blood cells and immune proteins rush to the site of an injury, and this is what results in increased blood flow to the area, which is experienced by the patient as localized warmth and redness. The high levels of certain chemicals in the blood act as irritants and can actually cause damage to the tissue and prolong the inflammatory process. Failure to control the inflammatory response may lead to a greater degree of tissue damage and poor healing. Uncontrolled inflammation underlies a variety of pathological conditions – for example, gout is caused by a reaction to uric acid crystals, which provokes an acute inflammatory response, resulting in severe pain and disability.
The knee is a weight-bearing joint and moves a great deal in the course of normal activity. It is vulnerable to a variety of problems, as a result of injury, illness, or the process of aging. Common knee problems include sprains, strains, torn cartilage, and a variety of sports-related injuries. A number of these conditions are associated with inflammation in the knee, and a patient’s presenting symptoms may include pain, swelling, and loss of mobility.
Causes of Knee Pain
Patellofemoral pain syndrome is a very common cause of knee pain in people under the age of 45. This is pain coming from the joint between the back of the kneecap and the front of the femur. It is common in people who have increased their level of activity, maybe starting a new exercise or job that involves a lot of knee bending or has been spending more time kneeling or squatting. It is also very common in females. The pain is usually diffuse in nature and often hard to pinpoint to a specific spot. This is because the pain is actually coming from the underside of the kneecap where it contacts the femur, but it can refer to the surrounding area.
The knee joint is a common area for overuse injuries. These are the types of injuries caused by repetitive motions, the sort that might come from simple everyday activities and cause both inflammatory and mechanical problems. On the other hand, there may also be an acute event such as an awkward fall or a violent collision from a tackle or other such accident. In these situations, there can be ligament and/or cartilage damage. Finally, there can be conditions that cause mechanical type injuries. An example of this might be someone with O or X legs developing a strain on one side of the knee because of the way they are walking due to their leg shape. There are other more serious alignment conditions such as scoliosis or an unequal length in the legs that can also cause mechanical problems in the knee.
Understanding Inflammation
A common error is the belief that inflammation is the source of pain for all things, and thus it must be removed to relieve the pain. This is not strictly true, as osteoarthritis sufferers can have little visible inflammation but significant pain. Osteoarthritis is treated by painkillers and anti-inflammatory drugs, the latter of which reduces the inflammation but not always the pain. In rheumatoid arthritis, it is the chronic systemic inflammation that destroys juxta-articular bone and causes the cartilage to disintegrate, leading to pain and loss of joint function. High levels of inflammatory cytokines have been associated with increased pain perception in OA and RA sufferers.
Inflammation is the body’s natural response to an irritant, be it a foreign body or the body’s attempt at repairing damaged cells. There are two types of inflammation: acute and chronic. Acute inflammation is identified by swelling, redness, heat, and pain. It occurs rapidly after an injury and is designed to help the body repair and relieve pain. Chronic inflammation can last months to years, and the prolonged presence of irritants and macrophages can cause damage to the cells and the cells’ genetic material. Inflammation is often associated with pain, but the relation between the two is not fully understood. In an acute injury, it is often the pressure of the inflammation on surrounding tissues that causes the pain. For example, with an ankle sprain, the pain often disappears after a few days as the acute inflammation dissipates.
Anti-inflammatory Strategies
Viscosupplementation has become another popular medication for knee pain. This involves injection of a thick hyaluronic acid-like fluid into the knee joint. This is thought to provide lubrication and cushioning to the joint and act as a further barrier to protect the joint from the chemical inflammatory mediators. This treatment can provide good relief of symptoms in patients with mild to moderate knee osteoarthritis. Corticosteroid injections can also be used, but these are generally not recommended due to systemic side effects and risks, and that they mask symptoms and do not effectively treat the underlying problem. Corticosteroid injections are also detrimental to the health of the knee joint in the long term.
Medications for Knee Pain
At present, there are no drugs that are effective in slowing or reversing the cartilage damage in osteoarthritis. However, there are studies that have suggested that the dietary supplements known as glucosamine and chondroitin may be effective in reducing the symptoms of osteoarthritis in some individuals. Glucosamine and chondroitin are substances that are found naturally in the body and also within the cartilage of our joints. They are the building blocks for cartilage and are believed to help repair damaged or worn-out cartilage, possibly by having an anti-inflammatory effect and slowing its breakdown. Both supplements are available at most pharmacies and are generally well-tolerated without any severe side effects. Although they should not be seen as a cure for knee pain, they are likely the safest option in treating osteoarthritis when compared to other drugs or preparations.
In more severe cases of arthritis or other inflammatory knee pain, steroid preparations may be recommended by a knee pain doctor Singapore. This is not to be confused with the anabolic steroids that are sometimes abused by athletes. These steroids come in the form of corticosteroid injections and oral or IV preparations. Although not a painkiller, corticosteroids are very effective at reducing inflammation and have been shown to be more potent than NSAIDs. They are often prescribed for those with severe osteoarthritis of the knee or other forms of rheumatoid arthritis and provide relief for pain and an improvement in the function of the knee.
Another type of painkiller that is sometimes used in knee pain treatment are the co-codamol and co-dydramol preparations. These are the only types of painkillers that are effective for severe pain which must be prescribed by a doctor. They are not recommended for long-term use, and are also not suitable for those with asthma or breathing difficulties. They work by blocking pain signals that are sent to the brain; however, they do little to help reduce inflammation and can sometimes cause drowsiness. It should be noted that painkillers come in a wide variety of types and strengths, and it is best to discuss with a pharmacist or doctor on which one is most suitable for your condition.
For knee pain sufferers with inflammation, medications are often part of the recommended treatment plan. There are several different types of drugs that are used in the treatment of knee pain. Some are used primarily to relieve pain, while others are used to reduce inflammation. The most widely used drugs for relief of arthritis or inflammation and knee pain are the NSAIDs. These are often used in the treatment of rheumatoid arthritis as well as other forms of arthritis. The name “non-steroidal anti-inflammatory drug” reflects the drugs’ ability to provide pain relief and reduce inflammation. This group of drugs includes such familiar names as ibuprofen, diclofenac, celecoxib, and naproxen among others. These drugs are effective at relieving pain and reducing inflammation, and are relatively safe. However, it should be noted that those with peptic ulcer disease or renal impairment should seek the advice of a doctor before using NSAIDs. This is because these drugs can sometimes cause gastric irritation and, in some instances, affect renal function.
Physical Therapy and Exercise
Apart from exercise, the patient would also be educated on the activities or lifestyle changes he/she could possibly make to reduce knee pain or pressure on the knee joint. This would include reducing the amount of time spent on activities that aggravate the knee pain, avoiding excessive stair climbing or walking up steep hills, using a walking aid (e.g. crutch, walking stick), or wearing supportive footwear.
Physiotherapy involves different techniques and exercises that are used to help maintain the functions of the body. In relation to knee pain and inflammation, physiotherapy would involve exercises that help to improve strength and flexibility in the knee and the muscles around it. Exercises that have been known to help with knee pain include aerobic exercise (low impact, e.g. swimming, cycling), strength training exercises, range of motion exercises, and stretching. Aerobic exercises help to increase function and decrease pain in the knee. It also helps to control weight, which can have a significant effect on reducing knee pain. Strength training is important for stabilizing the knee and reducing pressure on it. It involves exercises using weights, machines, and resistance bands. Sessions should be started at a low weight and progressed upon as muscle strength increases. Although it should be noted that aggravating knee pain could occur if these exercises are done incorrectly. Range of motion with stretching exercises help to maintain and increase the motion in the knee and are particularly important for patients that have arthritis. Static cycling is also one of the best exercises for the quadriceps, hamstring, and gastrocnemius muscles without loading the knee joint.
Lifestyle Changes for Managing Inflammation
Anti-inflammatory lifestyle changes are important for decreasing inflammation and preventing the progression to arthritis. For overweight patients, weight loss can have a very important impact. Some studies show that reduction in weight can decrease the risk for developing symptomatic knee arthritis. National and international guidelines for management of knee osteoarthritis recommend weight loss to reduce stress on the joints and prevent progression of disease. For example, the EULAR (European League Against Rheumatism) guidelines recommend “body weight reduction for symptomatic relief (at least relative risk reduction).” Weight loss strategies involve dietary modification and increased physical activity. Exercise has the added benefit of strengthening the muscles around the joint, which can reduce the load on the joint and improve shock absorption. This is discussed further below under “2.4 Exercise and Physical Therapy.” High-impact, load-bearing activities and sports may be contraindicated for patients with painful knees, but in general, regular physical activity is important for maintaining joint health. Aerobic exercise is to be encouraged, and patients should be advised that some increase in pain during exercise is acceptable, provided that it does not cause a flare lasting more than 48 hours. Adherence to weight loss and exercise programs may be difficult, and referral to a physiotherapist or occupational therapist with an interest in arthritis or a community-based health educator may be helpful. Step one of the Weight Watchers program was shown to be successful for weight loss in a trial involving overweight patients with knee osteoarthritis.
Singaporean Doctors’ Recommendations
Despite the successes of certain natural remedies, it is always important to maintain a healthy level of skepticism and not be drawn into common misconceptions. One highly publicized natural remedy is the consumption of gelatin. Although gelatin is made from animal by-products that are rich in collagen, there is scant evidence to suggest that eating gelatin will help to rebuild lost cartilage. Collagen molecules are broken down in the process of digestion and are distributed evenly in the body, so targeted supplementation of collagen at a specific site is a highly unlikely possibility.
Another common natural remedy is the use of Traditional Chinese Medications. There are herbal medications that are applied topically over the skin, and there are those that are consumed like medication. Patients have reported varying results with such treatments, and it is difficult to provide a general recommendation. Some of the medications may actually contain active ingredients that can reduce inflammation or rebuild cartilage. These ibuprofen-like medications would be effective for reducing pain and inflammation, while the effects of other herbals may be negligible at best.
Before visiting an orthopaedic surgeon, I always encourage my patients to try natural remedies. In fact, some of the alternative treatments, such as glucosamine and chondroitin supplements, have been shown to be quite effective for certain patients. Glucosamine and chondroitin are natural compounds found in the body that are used to build and maintain healthy cartilage. These supplements can be purchased over the counter and are best for patients with mild to moderate knee pain. It may take several weeks to months before the effects are noticed, and there are no known side effects, so I recommend a trial of these supplements for at least three months. If the supplements do not help after this period, then I do not think the patient will receive any significant benefit from continued use.
Traditional Remedies for Knee Pain
In a more radical approach, Dr. Kevin Lee, location Director of the Singapore Sports and Orthopaedic Clinic, suggests acupuncture, “an old Chinese woman’s tale.” The quick, non-invasive procedure is considered safe and effective for many conditions, according to the National Institute of Health. Dr. Lee explains, “acupuncture has scientifically shown to release endorphins, which are natural pain killers. Additionally, it can block transmission of pain to the brain and reduce inflammation.” Step therapy can be administered for advanced osteoarthritis, where the knee is realigned as the tibia is drilled through wedge osteotomy. This is followed by the unloading of the affected compartment by use of a Uni-compartment knee brace and stick to avoid a knee replacement. Acupuncture and step therapy provide a durable outcome for the patient looking to avoid or delay joint replacement.
Of the traditional remedies recommended by healthcare professionals in Singapore, “hot and cold therapy is cheap and practical,” notes Dr. Wai. The application of hot or cold packs, or alternating between the two, can help promote blood flow, giving relief and promoting the healing of the affected area. Dr. Tay recommends glucosamine cream; “when applied, it is warm to the skin as it emulsifies, this suggests increased blood flow. I would recommend this as a cost-effective self-treatment for mild knee pain.” Glucosamine supplements, a natural compound found in healthy cartilage, provide some pain relief for osteoarthritis in the knees and have been marketed in many oral forms as an alternative to nonsteroidal anti-inflammatory drugs, albeit lacking a significant amount of scientific evidence supporting their usefulness.
Innovative Treatments for Inflammation
Mesenchymal stem cell therapy is a relatively new and experimental mode of treatment, which uses bone marrow-derived stem cells with the potential to differentiate into different types of tissue. It has been described as a form of “cell therapy for damaged tissue using the natural restorative processes of the body”. These cells have been shown to have anti-inflammatory effects in arthritic knees in rabbits, and a clinical trial assessing safety and efficacy is now in the pipeline in Singapore. This is an exciting prospect as it represents a potential treatment not only for the symptoms of arthritis but also the damage to articular cartilage, which is so commonly associated with it. With both of these innovative treatments, it is essential to be aware that they are, as yet, unproven and carry unknown risks as well as benefits.
Innovative treatments aim to modulate the proinflammatory response locally and more selectively, without the systemic side effects of oral medication. A novel therapy involves the injection of a preparation rich in anti-inflammatory cytokines into the knee joint. These cytokines are signaling proteins secreted by white blood cells and are known to inhibit or reduce inflammation. Studies are presently underway assessing the optimal dosing, as well as safety and efficacy of this form of treatment.
There is evidence for diet and exercise as effective anti-inflammatory strategies, although the application of these strategies can be difficult in the elderly who have chronic knee pain. Bariatric surgery is an extreme but highly effective measure, particularly in patients with knee osteoarthritis who are morbidly obese. High-quality research is warranted for the evidence of manipulation and massage for knee inflammation in osteoarthritis.
Physiotherapy is an effective anti-inflammatory strategy in acute knee injuries to prevent chronic issues; however, its efficacy in chronic knee pain is less elucidated. The wealth of evidence for acupuncture and yoga therapy is somewhat surprising, particularly in Western culture. Further studies on these alternative therapies may open up new doors for patients unable to be adequately treated with Western influences. Data from the multitude of herbal medicine and alternative medicine therapies is inconclusive, and further study is required in these therapies to demystify what is culturally perceived as ancient wisdom.
The use of anti-inflammatory strategies for the knee joint has been widely researched, and the efficacy well documented in scientific literature. With such a wide variety of strategies tailored to a wide range of causes of knee pain, few strategies have proven to be effective across the board. There are applications for a range of anti-inflammatory pharmacological agents, widely differing in price, availability, and side effect profile. Future studies will further delineate which patients are most likely to benefit from a particular anti-inflammatory strategy to provide personalized treatment.