• Sharebar
advertisement: 
Knee Replacement

What Is Knee Replacement?

Last modified: 
16/04/2013 - 13:53

Contributing Author: Guy Slowik FRCS

Total knee replacement (TKR), also referred to as total knee arthroplasty (TKA), is a surgical procedure where worn, diseased, or damaged surfaces of a knee joint are removed and replaced with artificial surfaces. Materials used for resurfacing of the joint are not only strong and durable but also optimal for joint function as they produce as little friction as possible.

The "artificial joint or prosthesis" generally has two components, one made of metal which is usually cobalt -chrome or titanium. The other component is a plastic material called polyethylene.

The procedure has been proven to help individuals return back to moderately challenging activities such as golf, bicycling, and swimming. Total knees are not designed for jogging, or sports like tennis and skiing (although there certainly are people with total knee replacements that participate in such sports).

The general goal of total knee replacement is designed to provide painless and unlimited standing, sitting, walking, and other normal activities of daily living

Nice To Know:

With proper care individuals who have had a total knee replacement can expect many years of faithful function. Studies show that patients can expect a greater than 95 percent chance of success for at least 15 years.

If You Are Considering Total Knee Replacement Surgery

If you have been told you have a severely damaged knee joint and would benefit from a total knee replacement, the questions you need to ask yourself are:

  1. Have all of the appropriate non-surgical treatments been tried.
  2. Is my painful knee significantly restricting my day to day activities and not allowing me to do the things I need to do and the things I enjoy doing?

If the answesr to these questions are yes, you may be a candidate for a new knee.

The Anatomy Of The Knee Joint

The knee joint performs similar to a hinge joint. It consists of three bones:

  • Thigh bone (Femur)
  • Leg bone (Tibia)
  • Knee cap (Patella)
  • The junction where the femur and tibia couple together is called the femorotibial joint.
  • The region of the knee where the patella and femur form a junction is called the patellofemoral joint.
  • These two joints are what allow the bending and straightening of the knee. It is these joints that are replaced in a total knee joint replacement.

For a knee to function normally, the quality of smoothness where each bone moves upon the other becomes important in the function of the knee joint.

The surfaces of all three bones coming into contact with each other are normally covered with a smooth gliding surface known as articular cartilage.

The condition of this cartilage lining the knee joint is a key aspect of normal knee function and is important to the physician when evaluating a potential need for a knee joint replacement.

In addition to the smooth cartilage lining on the joint surfaces, there are two smooth discs of cartilage that cushion the space between the bone ends. The inner disc is called the medial meniscus, while the disc on the outer side of the knee joint is called the lateral meniscus. The role of the menisci is to increase the conformity of the joint between the femur and the tibia. The menisci also play an important function as joint shock absorbers by distributing weight-bearing forces, and in reducing friction between the joint segments.

Generally speaking, there are four major ligaments that play an important part in stability of the knee joint. One on each side of the knee (but actually outside the joint) known as collateral ligaments and two more centrally located ligaments within the joint known as anterior and posterior cruciate ligaments.

Facts About Total Knee Replacement

  • Total knee replacement surgery helps more than 250,000 Americans get back on their feet each year.
  • Over the last twenty-five years, major advancements in artificial knee replacement have greatly improved the outcome of the surgery.
  • Technology has led to the development of materials used in the artificial knee joint allowing it to last over fifteen years.
  • Artificial joint replacement for arthritis of the knee and hip is one of the most successful surgeries of the last century.
  • Individuals are able to begin walking the day following surgery and pain relief is achieved in greater than 95% of people.
This article continues: 

Knee Replacement

advertisement: 
 
advertisement: 
Rate This Article: 
Average: 4.3 (4 votes)

Related Library Articles

 

From Andrew Maynard - Chair of the University of Michigan Department of Environmental Health Sciences, with help from David Faulkner - 2013 Master of Public Health graduate.