ARTIFICIAL KNEES

Veronica Frattaroli

November 29, 2011

WHAT DOES AN ARTIFICIAL KNEE ENTAIL?

Usually 3-4 parts: A cap for the femur A cap for the tibia A plastic spacer Sometimes a back for the patella

KNEE REPLACEMENT

Two types of knee replacement: Total knee replacement: more commonly used and for more severe

damage

Partial knee replacement: still in research but is sometimes used for less severe damage

USES

Used to fix many conditions and diseases: Osteoarthritis Rheumatoid arthritis Avascular necrosis Malalignment of the knee joint (knock-knees or bowlegs)

TOTAL KNEE REPLACEMENT

Advantages: Lasts up to 20 years Good relief of previous pain Good range of motion (0-120°)

Disadvantages: Stiffness Pain Loss of motion

PARTIAL KNEE REPLACEMENT

Advantages: Sometimes an outpatient procedure Can possibly stand with assistance within 2 hours of surgery

Disadvantages: Not as widely used

PROCEDURE

Vertical incision along the knee Distal femur is shaped, using a customized device, to properly

align the bone to the leg’s original angles Proximal tibia is also shaped, using a similar device as the

femur, to align the bone correctly If the patella is severely damaged, the undersurface is

removed Metal caps are attached to the appropriate bone using an

epoxy cement Then a plastic spacer is placed on top of the metal cap of the

tibia, made of polyethylene (can be replaced to prolong joint life)

PROCEDURE CONT.

RISKS

Blood clots Infection in the surgical wound or in the joint Nerve injury Problems with wound healing Lack of good range of motion Dislocation of patella Fracture of the patella Instability in the joint

FUTURE

Advances in diagnosis and management of osteoarthritis

Advances in robotics

Less invasive surgery

REFERENCES

"Knee Replacement Surgery." WebMD Arthritis and Joint Pain Center: Symptoms, Causes, Tests, and Treatments. Ed. Anne C. Poinier. 2005. Web. 26 Nov. 2011

What Is Knee Replacement?" EhealthMD. Ed. Guy Slowik. EhealthMD, 28 June 2011. Web. 27 Nov. 2011.

"Total Knee Replacement." Meniscus Transplant and Biologic Knee Replacement to Avoid Knee Replacement by San Francisco Knee Specialist Kevin Stone MD. The Stone Clinic, 2011. Web. 27 Nov. 2011.