As a end result of which it can start tearing or flaking. Once the cartilage is lost due to degeneration, the shin bone and thigh bone are exposed to friction which may additionally increase Knee Pain bony outgrowths or spurs known as osteophytes. The above incidence makes the knee painful. Pain may occur additionally while rheumatic arthritis invades the sensitive tissues around the knee joint. Another purpose of knee ache due to arthritis is the crystallization of uric acid inside the joint cavity.