All joints wear with use like any bearing in a machine. In humans, these joints must be repaired otherwise the person would be worn out, probably by the age of five. The sympathetic nerves monitor this repair mechanism. It is surprising the damaged joint can often repair itself when the back problem is resolved.
Joint pain can also be associated with the toxins from a streptococcal infection, infections, injuries and autoimmune diseases.
Treatment woudl include Interx, Shiats, MET, and nutritional advice.