Knee replacement, also called knee arthroplasty or total knee replacement, is a surgical procedure to resurface a knee damaged by arthritis. Metal and plastic parts are used to cap the ends of the bones that form the knee joint, along with the kneecap. This surgery may be considered for someone who has severe arthritis or a severe knee injury.
Total knee replacement, where the entire joint is replaced with artificial surfaces.Partial knee replacement, where only one damaged compartment of the knee is replaced,Total knee replacement is the more common of these two procedures.
Most femoral components are made of metal alloys (cobalt chromium) or metal-ceramic alloys (oxidized zirconium). The patellar component is plastic (polyethylene). The tibial insert component is also plastic (polyethylene). The tibial tray component can be made of the following materials: cobalt chromium (metal alloy),titanium (metal alloy),polyethylene (plastic)
Knee replacement implants are expected to function for at least 15 to 20 years in 85% to 90% of patients. However, the implants do not last forever.
After a period of 15 to 20 years, general wear and tear may loosen the implant. Depending on the patient, this may cause no symptoms, or it may cause any of the following:
loose implant particles
When these symptoms arise, orthopedic surgeons recommend having knee revision surgery to replace the original implant. Infection, especially, requires a prompt revision surgery. Infection after knee replacement surgery is rare, but a knee replacement implant cannot defend itself from infection if bacteria are introduced to the body.
Most patients progress to a straight cane, walker or crutches within two or three days after surgery. As the days progress, the distance and frequency of walking will increase.Patients are usually able to drive a car within three to six weeks after surgery and resume most other normal activities by or before six weeks. Complete recuperation and return to full strength and mobility may take four months or more. However, in many cases, patients are significantly more mobile one month after surgery than they were before they had their knee replacement