There are several forms of arthritis which can affect the hip joint. They all tend to give the similar symptoms, perhaps progressing at different rates.
Most patients have primary osteoarthritis - wear a tear of the hip joint. This failure of the joint is due to accumulative damage over many years; the human body has only evolved to an average lifespan of 40 years! Where the hip has been damaged or diseased beforehand the rate of wear is accelerated and this is termed secondary arthritis.
Rare inflammatory conditions can affect the hip, such as rheumatoid arthritis, and need to be treated in a slightly different way.
In this document I have included a description of other conditions affecting the pelvic bones giving symptoms of x-ray changes that may be mistaken for arthritis:-
© Mr Gavin Holt :: CotswoldClinics.com :: Print this frame