After the Civil War , with the protection of the Thirteenth , Fourteenth , and Fifteenth Amendments to the Constitution and the Civil Rights Act of 1866 , African Americans enjoyed a period when they were allowed to vote , actively participate in the political process , acquire the land of former owners , seek their own employment , and use public ...
In the knee, for example, cracking or popping may occur if the patella (knee cap) is slightly out of alignment, and rubs on the adjacent tissues. Other causes of joint noise are the snapping of tendons or scar tissue over a prominence or something referred to as cavitation. Cavitation frequently occurs in synovial joints when a small vacuum forms in the synovial fluid and a rapid release produces a sharp popping or cracking sound.
A lubricating fluid called synovial (sih-NO-vee-ul) fluid helps your leg swing smoothly and reduces friction between the moving parts of your knee. But sometimes the knee produces too much synovial fluid, resulting in buildup of fluid in an area on the back of your knee (popliteal bursa), causing a Baker's cyst. This can happen because of: 1  Inflammation of the knee joint, such as occurs with various types of arthritis.  A knee injury, such as a cartilage tear.