The categorization of people by social strata occurs in all societies, ranging from the complex, state-based societies to tribal and feudal societies, which are based upon socio-economic relations among classes of nobility and classes of peasants.
Knee replacement, also known as knee arthroplasty, is a surgical procedure to replace the weight-bearing surfaces of the knee joint to relieve pain and disability. It is most commonly performed for osteoarthritis,[1] and also for other knee diseases such as rheumatoid arthritis and psoriatic arthritis.
An infected knee replacement usually requires surgery to remove the artificial parts and antibiotics to kill the bacteria. After the infection is cleared, another surgery is performed to install a new knee. Artificial knees can wear out. Another risk of knee replacement surgery is failure of the artificial joint.