Partial Knee Replacement
Partial knee replacement or Unicondylar Knee Replacement is the procedure where inner or medial side of knee joint is replaced with metal and polyethylene implant, whereas in Total Knee Replacement whole surface is replaced.
In about 20% of Osteoarthitis persons requiring replacement surgery only inner side is worn out badly while other parts of knee are nearly intact. Such persons are suitable for Partial Knee Replacement.
This type of replacement is done through a small cut, to remove damaged cartilage and bone from tibia and femur and appropriate zigs are used to make bone surfaces to receive specifically sized implants.
Who are not suitable for Partial Replacement
1. Arthritis is not confined to one part of joint.
2. Ligaments are stretchable and not contracted.
3. Knee has very limited range of movement
4. Presense of marked obesity.
5. Any type of inflammatory arthritis like Rheumatoid arthritis.
Pillars of Success
Selection of knee arthritis grade and evaluation of person is very important. The operative technique is very demanding and experience of surgeon is critical as well as how frequently surgeon is performing this replacement.
Frequently Asked Questions
Q: I have been told that I might benefit from partial knee resurfacing. Is this the same thing as partial knee replacement?
A: Yes. Partial knee replacement, partial knee resurfacing surgery, unicompartmental knee replacement, and unicondylar knee replacement all refer to the same procedure.
Q: Are there any age restrictions for partial knee surgery?
A: There are no strict recommendations, but in general, partial knee replacements are appropriate for patients over 55 years old who meet other eligibility criteria.
Q: What is the knee prosthesis made of?
A: Knee prostheses or implants are made of cobalt-chrome alloy and plastic. These surfaces are designed to glide smoothly against one another just as cartilage does in a healthy knee.
Q: Will I be able to resume bicycle riding/driving/sitting cross legged after my partial knee replacement?
A: Although not everyone can return to unrestricted activities, most are able to resume biking, driving and other daily activities.
Q: What kind of complications can occur with partial knee surgery?
A:Generally, complications occur less frequently after partial knee replacement than they do following total knee replacement.
As with any surgery, complications may include instability of the knee, loosening of the implant, infection, nerve injury and deep vein thrombosis.
Q: Is recovery from partial knee replacement painful?
A: All surgeries result in some pain. There is much less pain and stiffness following partial knee replacement compared to after total knee replacement.
Q: If I decide to have partial knee replacement, does that mean that I will no longer have arthritis in other part of the knee?
A: Partial knee replacement will address the arthritis that is present in the particular compartment of the knee that is affected. However, very few persons will develop arthritis in other part of knee as the age increases and should this occur, revision to a total knee replacement may be required.
Q: How long can I expect my partial knee replacement to last?
A: A well-done partial knee replacement in an appropriately selected patient can have a survival rate that is comparable to that achieved with a total knee replacement.
Dr. Dattatrey Mohapatra
Senior Consultant-Joint Replacement Unit