Osteoarthritis is the most common cause of pain and disability in knees. In the knee joint, smooth articulate cartilage, called surface cartilage, covers the ends of the femur (thigh bone) and tibia (shin bone). Between the two bones sits a second type of cartilage, called menisci, which acts as a shock absorber. Joint fluid also lubricates the knee joint.

Osteoarthritis (OA) starts as the lack or loss of surface cartilage, progressively involving the surrounding bone, tissues and synovial fluid. In OA, your knee cartilage may thin in spots or disappear completely, resulting in areas of exposed bone.

X-rays, MRI and knee arthroscopy can help you and your doctor to determine the right treatment plan, which may include these noninvasive options.

Non-Surgical Treatments for OA

1. Exercise and Weight Loss

Nonsurgical management of knee OA starts with weight loss and muscle strengthening. Each pound of weight can put up to 6 pounds of pressure on the knee joint during activity. Overweight people tend to develop arthritis at an earlier age and to a greater severity than non-overweight people. 

Muscle strength is also vital. The muscles surrounding the knee joint act as shock absorbers for the pressure that daily activities and sports place on the joint. The stronger the muscles, the more stress they can absorb.

Exercises to strengthen quadriceps, hamstring and calves include one-quarter squats, leg press and leg extension. These exercises should be pain free and done with limited bending of the knee, not greater than 45 degrees. Cardiovascular exercise, such as cycling, elliptical, rollerblading and swimming, will also help. Do strengthening exercises at least three times a week.

2. Bracing

Knee braces are available for medial compartmental osteoarthritis (arthritis on the inside of the knee joint). These braces work by relieving the weight from the affected side of the knee. Braces need to be custom made and can be expensive.

3. Medications

In addition to weight loss and strengthening, anti-inflammatory medications may help decrease symptoms. Over-the-counter, non-steroidal anti-inflammatory drugs (NSAIDs) include aspirin, ibuprofen (Advil) and Naprosyn (Aleve). Prescription-strength NSAIDs include Indocin, Daypro, Relafen, Celebrex, Lodine and Mobic. Acetaminophen (Tylenol) is less effective for inflammation than other medications. If you take anticoagulation medicine, use NSAIDs with caution.

4. Nutritional Supplements

Supplements such as glucosamine sulfate and chondroitin sulfate are widely used but not regulated by the FDA. Glucosamine is a primary component of connective tissue, including cartilage. Chondroitin sulfate is found in proteoglycans which contribute to the stability of cartilage. In supplementation form, chondroitin is derived from bovine and calf cartilage. Several clinical studies are in process evaluating effectiveness and monitoring any long-term adverse effects of glucosamine and chondroitin.

5. Viscosupplementation

The knee joint’s synovial fluid is highly viscous, which creates a friction-free environment. Hyaluronic acid (HA) is present in synovial fluid (and most body tissues). In a healthy adult, synovial fluid HA has a molecular weight of 4-5 million and forms coiled configurations that provide elasticity and viscosity to synovial fluid. HA also binds to proteoglycans to stabilize articulate cartilage.

With OA, the molecular weight of HA decreases, causing the synovial fluid to become less viscous and leading to increased friction.

Injections of Hylagan, a gel-like fluid, provide extra lubrication and shock absorption within the knee joint, as well as decrease friction or rubbing. However, only about 50 percent of people who receive injections experience symptom relief. The knee receives one injection each week for three weeks; injections may be repeated as soon as six months. Up to five injections may be given, but studies show no difference in symptom relief after 3 or 5 injections.

6. Cortisone Injection

Injection of cortisone into the knee joint can be effective for symptom flare-ups because they are a direct-acting anti-inflammatory medication. However, repeated cortisone injections may deteriorate articulate cartilage. Use these injections with caution.