Total Knee Replacement or TKR is complete resurfacing procedure of articular cartilage of Knee Joint. Here cartilage is replaced by metal prosthesis sitting on lower end of femur and upper end of tibia, in-between there is a plastic which provides a smooth gliding surface.
This is the most common indication for TKR. Osteoarthritis is degenerative wear and tear of articular cartilage. Risk factors for Osteoarthritis include old age, sedentary lifestyle, and obesity. It can be diagnosed on X rays. Non-surgical treatment include rest, ice, knee brace, cane for support, pain medication and physical therapy. TKR is the only permanent treatment option for end-stage osteoarthritis of knee.
Rheumatoid arthritis is a form of inflammatory arthritis where body's immune system attacks the joints. It is characterized by multiple joint pain, usually bilateral and symmetrical. Hands, feet, knees and hips are affected by Rheumatoid arthritis. Diagnosis can be made with help of X ray and laboratory investigations. Rheumatoid knees are more deformed and osteoporotic as compared to Osteoarthritic Knees. In some cases special implants are required for Knee Reconstruction.
It is a result of prior injury to knee – fracture around knee joint, ligament or meniscus injury. Any fracture involving articular surface of knee predispose it to arthritis. Ligament and meniscus injury causes instability resulting in repetitive micro trauma to cartilage.
TKR prosthesis in general have four components- femoral prosthesis, tibial base plate, articular surface and patella button. In Metal back variety, femoral and tibial components are made up of Cobalt-chromium or titanium alloys , whereas, articular surface and patella button are made up of Ultra High Molecular weight polyethylene. It is the most commonly used prosthesis.
In this variety, tibial component and articular surface are made up of one piece of plastic. It is a cheaper alternative to metal back prosthesis for elderly patients.
It is supposed to accommodate better flexion due to some design modification. None of the good quality studies has proven that Hi flex knee provide s better bending as compared to Metal back or all poly prosthesis.
Osteoarthritis Knee
After TKR