Osteoarthritis affects over 20 million Americans and this number is expected to rise to 40 million by the year 2020.  The total knee replacement or arthroplasty is usually the long term surgical procedure that is performed to allow a person the opportunity to regain function in the knee and return to an active lifestyle.  In the United States, over 267,000 total knee replacements are performed each year.  Candidates for total knee replacement have experienced painful arthritis in the knee that overtime causes pain and stiffness that may become constant.  Walking and going up and down stairs becomes difficult.  With knee joint replacement, there are a few options that may be available to the person suffering from osteoarthritis.  Most recently, surgeons in the United States are now performing a less invasive surgery with the use of a Unispacer.  The Unispacer is a small, lightweight, C-shaped cup that acts as a cushion between the tibia and femur to fill the space where the cartilage has worn away.  When performed on patients that are the correct candidates, this surgery may postpone the need for a total knee replacement for up to ten years.  Another option in replacement surgery is the unicompartmental replacements, where the resurfacing in the knee is done on the tibia and femur but only on one side of the joint.  This procedure has the advantage of acting more like one’s own knee than a total knee replacement.  Again, the patient must fit certain criteria to be a surgical candidate for this surgery.  The total knee replacement has been the standard surgery since the 1970’s for patients that exhibited a significant arthritic knee condition and has evolved to become a very successful surgery.