Osteoarthritis (OA, also known as degenerative arthritis, degenerative joint disease), is a condition in which low-grade inflammation results in pain in the joints, caused by abnormal wearing of the cartilage that covers and acts as a cushion inside joints and destruction or decrease of synovial fluid that lubricates those joints. As the bone surfaces become less well protected by cartilage,  pain is experienced upon weight bearing, including walking and standing. Due to decreased movement because of the pain, regional muscles may atrophy, and  ligaments may become more lax.

The main symptom is chronic pain, causing loss of mobility and often stiffness. "Pain" is generally described as a sharp ache, or a burning sensation in the associated muscles and tendons.

OA can cause a crackling noise (called "crepitus") when the affected joint is moved or touched, and patients may experience muscle spasm and contractions in the tendons. Occasionally, the joints may also be filled with fluid. Humid weather increases the pain in many patients.

Treatment

Generally speaking, the process of osteoarthritis is irreversible, and typical treatment consists of medication or other interventions that can reduce the pain of OA and thereby improve the function of the joint.

Natural treatment options may include:

• Weight control
• Appropriate rest
• Acupuncture. 
  • A meta-analysis of randomized controlled trials of acupuncture for knee osteoarthritis concluded "clinically relevant benefits, some of which may be due to placebo or expectation effects" 
• Heat. Heat can ease inflammation and swelling, and may improve circulation, which has a healing effect on the local area.
• Regular exercise, if possible, in the form of walking or swimming, is encouraged. Applying local heat before, and cold packs after exercise, can help relieve pain and inflammation, as can relaxation techniques.
• Dietary. Nutritional changes shown to aid in the treatment of OA include decreasing saturated fat and using a low energy diet to decrease body fat. A low fat vegetarian diet can reduce arthritis symptoms. A macrobiotic diet has been known to reduce symptoms as well.
• Supplements.There have been several studies showing potential benefits of dietary supplements for treating OA . Potential treatment options may include:
• Glucosamine. Supplemental glucosamine may improve symptoms of OA and delay its progression. The jury is still out as there are studies that show the benefit, while other studies conclude that glucosamine hydrochloride is not effective and that the effect of glucosamine sulfate is uncertain.
• Chondroitin sulfate . Along with glucosamine, chondroitin sulfate has become a widely used dietary supplement for treatment of osteoarthritis. The Osteoarthritis Research Society International is in support of the use of chondroitin sulfate for OA, however there have been studies which have found no benefit from chondroitin.
• Antioxidants, including vitamins C and E in both foods and supplements, provide pain relief from OA.
• Boswellia, an herbal supplement known in Ayurvedic medicine. It is widely available in health food stores and online.
• Ginger (rhizome) extract - has improved knee symptoms moderately.
• Hydrolyzed collagen (hydrolysate) (a gelatin product) may also prove beneficial in the relief of OA symptoms, as substantiated in a German study by Beuker F. et al. and Seeligmuller et al. In their 6-month placebo-controlled study of 100 elderly patients, the verum group showed significant improvement in joint mobility.
• Omega-3 fatty acid, a vitamin supplement comprised of important oils derived from fish.
  • Recent studies have shown that plant-based omega-3 polyunsaturated fatty acids (PUFA) contained in such foods as flaxseed and walnuts may have a protective effect on bone health, according to a team of Penn State researchers who carried out the first controlled diet study of these fatty acids.
• Selenium deficiency has been correlated with a higher risk and severity of OA.
• Vitamins B9 (folate) and B12 (cobalamin) taken in large doses significantly reduced OA hand pain, presumably by reducing systemic inflammation.
• Vitamin D deficiency has been reported in patients with OA, and supplementation with Vitamin D3 is recommended for pain relief.