Partial knee replacement.

Partial, or unicompartmental, knee replacement is performed when only a single compartment of the knee is affected by arthritis.

This could involve the inside (medial), outside (lateral), or front (patellofemoral) joint.

Total knee replacement.

Total knee replacement is performed for end-stage arthritis and involves replacing the entire ends of the femur and tibia.

In some instances, the patella (knee cap) will be resurfaced as well.

Revision knee replacement.

Revision (re-do) knee replacement is performed when a prior knee replacement fails. Potential causes include infection, pain, or loosening. Surgery involves removal of the previous replacement and insertion of new components.