Great info as always from txsilver. Also could be caused by genetic defect such as shallow hip sockets, this caused Olympian Mary Lou Retton to have both hips replaced.
Also could be caused by mycoplasma, tiny organism without cell walls and receptors, this can be detected by live blood analysis - I am working with this right now and definitely seeing improvement, less pain and I'm completely off Motrin which is good because it was causing gut problems for me. Some people have found a gluten free diet helps too. I've been doing this for several months even though I love bread. In my opinion it makes sense to try all the non-drug, non-surgery alternatives first.
osteoarthritis is a degenerative condition. It is caused by the breakdown of cartilage and is often associated with aging. It can be assisted along the way by injuries. There is no cure for osteoarthritis. Treatments include NSAIDs and pain management, maintaining a normal weight and exercise.