Every joint is covered with smooth cartilage and lubricated by joint fluid. From our twenties onwards the cartilage slowly loses quality, the lubrication decreases and the bone surface changes. This process is osteoarthritis, also called arthrosis or wear and tear. It happens to everyone; there are even traces of it in Neanderthal skeletons. It mainly affects the weight bearing joints, the knees and hips, and the small facet joints of the lower back and neck. Risk factors are age, a previous injury, heavy or repetitive loading, overweight and family history.
The important point: osteoarthritis on an X ray does not equal pain. Many people with clear wear on a scan have no complaints, and many painful joints show little on imaging. Pain comes from a joint that has stopped moving well, from the guarding muscles around it and from irritated nerves, and those are exactly the things we can treat. A chiropractor or physiotherapist does not treat the cartilage; we treat the consequences, so the joint moves more freely and hurts less. For knees and hips in particular, see also our page on hip and knee pain.
