1. Health
You can opt-out at any time. Please refer to our privacy policy for contact information.

Partial Knee Replacement

Minimally invasive partial knee surgery


Updated May 16, 2014

partial knee replacement

Arthritis confined to a part of the knee may be treated with a partial knee replacement.

Image © Medical Multimedia Group
Partial knee replacement, also called a unicompartmental knee replacement, is a surgery that may be considered for treatment of severe arthritis of the knee. Traditionally, patients have undergone total knee replacement for severe arthritis of the knee joint. In a total knee replacement, all cartilage is removed from the knee joint, and a metal and plastic prosthetic is implanted.

The partial knee replacement surgical procedure has generated significant interest because it uses a smaller incision and has faster recovery than traditional total knee replacement surgery. Partial knee replacement is a type of and minimally invasive surgery. The idea is to remove only the most damaged areas of cartilage from the joint, and leave any healthy parts of the joint for continued use. Most often, partial knee replacements use implants placed between the end of the thigh bone and the top of the shin bone. Partial knee replacements can also replace the part of the joint under the kneecap, a patellofemoral replacement.

Is Partial Right For You?

The minimally invasive partial knee replacement is designed for patients who have severe arthritis of the knee that have not found relief with standard conservative treatments. The treatments may include medications (such as Advil, Naprosyn, and Celebrex), cortisone injections, strengthening exercises, and weight loss. If these treatments are not sufficient, and you are not satisfied, then surgery may be considered.

The partial knee surgery may be possible if the arthritis in the knee is confined to a limited area. If the arthritis is widespread, then the partial knee replacement is not appropriate, and should not be considered. In addition, the partial knee surgery is recommended in patients who are:

  • Older than 55 years
  • Not obese
  • Relatively sedentary
  • Have intact ligaments (specifically the ACL)
If these qualifications are not met, then the minimally invasive partial knee surgery may not be as successful. Unfortunately, many patients are therefore ineligible for this minimally invasive procedure.

The Downside of Partial Replacements

Many patients who are interested in a partial knee replacement have arthritis that is too advanced for the minimally invasive procedure. Because surgical treatment is considered a last-resort by most patients, by the time surgery is necessary, their arthritis may be too advanced to consider this procedure. If partial knee replacement is done in a patient who is a poor candidate, failure rates can be high, and conversion to a total knee replacement may be necessary.

Benefits of Partial Knee Replacement

  • Smaller Incision
    A traditional knee replacement surgery involves an incision about 8 inches over the front of the knee. There is more significant dissection necessary to complete the procedure compared to the partial knee surgery. In the minimally invasive partial knee replacement, the incision is about 4 inches, and the amount of dissection and bone removal is much smaller.

  • Less Blood Loss
    Because of the extent of dissection and bone removal necessary for a total knee replacement, the need for a blood transfusion is relatively common. With the partial knee procedure, a blood transfusion is infrequently needed, and patients do not need to consider giving blood before surgery.

  • Shorter Recovery
    Both the time in hospital and the time to functional recovery are less with the partial knee replacement. Patients are known to have been discharged on the day of the procedure, although most often patients are discharged on the first or second post-operative day. With traditional total knee replacement, patients seldom leave before three days in the hospital, and may require a stay in an in-patient rehabilitation unit.
Related Video
Prenatal Yoga Head-to-Knee Pose
  1. About.com
  2. Health
  3. Orthopedics
  4. Hip & Knee
  5. Hip & Knee Replacement
  6. Replacement Alternatives
  7. Partial Knee Replacement

©2014 About.com. All rights reserved.

We comply with the HONcode standard
for trustworthy health
information: verify here.