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Knee pain can be caused from a few different diagnoses, including osteoarthritis (caused by mechanical "wear and tear" on the knee joint over time the most common cause), rheumatoid arthritis (caused by autoimmune problems), infectious arthritis, old knee injuries, or patellar dysfunction to name a few. It is key to see a doctor to establish the correct diagnosis because the best treatment and management plan depends specifically on what is going on inside your knee. Similarly, if you have been diagnosed with osteoarthritis, for example, but find that it is not improving with treatments, speak to your doctor about the possibility of investigating other possible diagnoses. Each pound of weight gain puts up to six more pounds of pressure on the knee joint. Thus, overweight people tend to develop arthritis more frequently than those at a healthy weight. To prevent future knee pain (and to lessen symptoms that already exist), try to maintain a healthy weight, primarily through diet (exercise may be limited by the presence of knee pain). People with arthritis are advised to avoid processed or fried foods, sugars, refined carbohydrates, salt, preservatives, and corn oil, all of which may aggravate the inflammation of the joint directly or through weight gain. Muscles around the joint act as shock absorbers, helping to support and stabilize the joints both in physically demanding situations (such as during sports and exercise) as well as in your daily activities. The stronger the muscles are, the greater stress they can absorb. To help prevent crepitus (and, if you already have it, to reduce it), gradually build the muscles around your joint through strength exercise. For knee crepitus, thigh contraction is a great exercise that strengthens muscles around the knee joint. Place a rolled-up towel under your knee and tighten your thigh muscles. Hold it for five seconds and relax and repeat again for 10 times. Isometric exercises such as straight leg raises ( with the knee locked), quad sets, or wall sits can strengthen the joint while limiting motion through the involved joint. This avoids aggravating the joint and increasing pain and inflammation). Low-impact cardio exercises such as biking or swimming may also be done (recommended at least three times a week) to improve the muscle strength of the thigh and calf. These exercises can also help you lose weight, further reducing crepitus pain. Both have been shown to help people diminish the pain that is often associated with knee crepitus. Try experimenting with icing and/or heat to see if it works for you. Certain nutritional supplements, including glucosamine sulfate and chondroitin sulfate, are used by some arthritis sufferers to treat and/or prevent crepitus. However, these supplements are not regulated by the FDA and have not yet been scientifically proven to work. There is also little information on any side effects from long-term use of these supplements. Clinical studies are underway to evaluate these supplements for medical use. In the meantime, talk to your doctor or someone you trust who has tried these dietary supplements before beginning to take them.

Summary:
Make sure you have the correct diagnosis. Manage your weight. Exercise. Try a combination of ice and heat packs. Cautiously consider dietary supplements.