Arthroplasty (Knee – Hip Replacement)

Arthroplasty (Knee – Hip Replacement)

Arthroplastyn

KNEE ARTHROPLASTY

 

During a knee replacement surgery, an orthopedic surgeon carves away the damaged part of the knee and replaces it with an artificial joint made of metal or plastic. The artificial joint is then attached to the thigh bone, shin, and kneecap with a special material such as acrylic cement.

Why Knee Replacement Surgery is required?

Osteoarthritis is the main reason why people go for knee replacement surgery. The age-related condition is very common and occurs when cartilage — the cushion between the knee and the bone joints — breaks down.Other reasons include:

  • Rheumatoid arthritis : Rheumatoid arthritis is when the body’s immune system attacks and destroys the lining of the knee.
  • Deformities: People with bowed legs or “knock-knees” often get surgery to restore the position of the knee.
  • Knee injuries : A broken bone or torn ligaments around the knee sometimes will result in arthritis that causes great pain and limits your movement.
  • Loss of blood flow: Doctors will recommend surgery if blood stops flowing to the bones (a condition called either osteonecrosis or avascular necrosis).

 

How Long Do They Last?

Doctors first started replacing knees in the early 1970s. Back then, surgeons said the new knees would last about a decade or so. Today’s implants will last 20 years.

 

HIP ARTHROPLASTY

Hip replacement surgery is a procedure in which a doctor surgically removes a painful hip joint with arthritis and replaces it with an artificial joint often made from metal and plastic components. It usually is done when all other treatment options have failed to provide adequate pain relief. The procedure should relieve a painful hip joint, making walking easier.

In a total hip replacement (also called total hip arthroplasty), the damaged bone and cartilage is removed and replaced with prosthetic components.

  • The damaged femoral head is removed and replaced with a metal stem that is placed into the hollow center of the femur. The femoral stem may be either cemented or “press fit” into the bone.
  • A metal or ceramic ball is placed on the upper part of the stem. This ball replaces the damaged femoral head that was removed.
  • The damaged cartilage surface of the socket (acetabulum) is removed and replaced with a metal socket. Screws or cement are sometimes used to hold the socket in place.
  • A plastic, ceramic, or metal spacer is inserted between the new ball and the socket to allow for a smooth gliding surface.