To better understand osteoarthritis, it helps to understand the anatomy of the joints.
The bones in all joints have a smooth lining called articular cartilage. Cartilage provides a gliding surface to help joints move. All joints are lubricated with a slippery liquid known as synovial fluid.
Joint cartilage may break down due to inflammation, overuse or injury. This can result in the bones of a joint making contact. This in turn causes abnormal bone growth, more inflammation, pain and stiffness.
Anatomy of joints commonly affected by osteoarthritis:
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