Oxford Partial Knee Replacement

What is a partial (unicompartmental) knee replacement?

The knee is divided into three areas or compartments: the medial (inner) compartment, the lateral (outer) compartment, and the patellofemoral (kneecap) compartment. When a knee is severely arthritic, one, two, or all three compartments can be affected. In about 30% of patients, the wear is predominantly in one compartment. If this is the case, partial knee replacement can be considered rather than a total knee replacement.

oxford partial knee replacement modelPartial knee replacement devices consist of three parts: the femoral component (the metal cap for the femur bone); the tibial component (the metal cap for the tibial bone); and an insert or “liner” placed between the two metal components. The liner is made of a specially machined plastic called ultra high molecular weight polyethylene. In essence, the liner takes the place of the cartilage that is missing in an arthritic knee and the metal protects the bone.

What are the potential advantages of a partial knee replacement over a total knee replacement?

Only the problem area of the knee is resurfaced. As the implant is smaller, less surgical cutting and exposure is necessary to complete the procedure. As a result, only the bone and the soft tissues (tendons, ligaments) that are unhealthy are reconstructed. The good parts remain unviolated.

In many patients, this can:

• Decrease surgical time
• Decrease the length of time in the hospital
• Decrease blood loss
• Decrease the ultimate recovery time
• Result in an earlier return to work/full activity
• Provide increased range of motion (compared to total knee replacement)

What is a “minimally invasive technique”?minimally invasive knee surgery

The term “minimally invasive” has been used pervasively over the past 5-7 years in joint replacement surgery. Often one surgeon’s definition is quite different from another’s. In general, a minimally or less invasive technique is one that allows for a procedure to be completed with less cutting, through a smaller exposure. Although patients will notice the size of a scar (which is one component), most surgeons feel the more important aspect is actually the “deeper” exposure. The less we need to mobilize or cut tendons, ligaments, muscles, and bone, the less the patient will have to recover.

Can an Oxford partial knee replacement be performed through a minimally invasive technique?

Yes. Oxford partial knee replacement is less invasive on the bone and the device is implanted through a smaller skin incision and a smaller deep incision. Most importantly, the quadriceps is not violated at all making it a “quadriceps-sparing” approach. This may lead to earlier restoration of quadriceps function, the most important muscle-tendon unit about the knee, and may allow for earlier return to full function. Oxford partial knee replacement may be performed as outpatient (same day) surgery.

What is the difference between an Oxford partial knee replacement and other partial knee replacements?

The Oxford partial knee replacement has a mobile bearing insert between the two metal components, rather than a fixed bearing insert. This mobile bearing insert allows for movement during knee motion, potentially restoring better motion dynamics (kinematics) of the knee. In most other partial knee replacements, the liner is a fixed bearing and does not move with the knee during motion.

What are the results of the Oxford partial knee replacement?

The Oxford partial knee replacement has the best track record of any partial knee replacement. There is published 20 year data that shows a 94% success rate at 20 years. This is comparable to the best total knee replacement data and superior to other partial knee replacement data.

What are the risks of an Oxford partial knee replacement?

Although uncommon all the following have been reported: infection, bleeding, progression of osteoarthritis in the other compartments, fracture of the bone during implantation, injury to ligaments, nerves, or blood vessels, stiffness of the knee, persistent pain in the knee, swelling, dislocation of the liner (spin out), loosening of the prosthetic, blood clots, and adverse reaction to anesthetics.

What activities can I do after an Oxford partial knee replacement?

You may perform all low and medium impact activities. Unlimited walking, hiking, bicycling, swimming, golf, bowling. No specific lifting restriction is present. We discourage high impact sports such as the running, jumping, or cutting sports such as soccer, basketball, or football. Skiing and doubles tennis are permitted. We recommend against vigorous skiing where accidents may occur such as fractures. We also recommend against overly competitive doubles tennis. Although a person can do these activities, higher impact activity can lead to early failure of the device in any joint replacement including all partial knee replacements. They were not designed to withstand high impact activities over a long period of time.

Knee Pain Treatment

Partial Knee Replacement

In partial knee replacement, only the damaged surface of the knee joint is replaced, leaving healthy bone and tissue intact. About 20% of our patients are potential candidates for partial knee replacement and average recovery time is about one-half that of total knee replacement recovery.Partial knee replacements can be performed as outpatient (same day) surgery… (read more)

MAKOplasty® Partial Knee Resurfacing is a innovative treatment option for adults living with early to midstage osteoarthritis (OA) in either the medial (inner), patellofemoral (top), or both compartments of the knee. The surgery is powered by the RIO® Robotic Arm Interactive Orthopedic System, which allows for consistently reproducible results in precision partial knee resurfacing…. (read more)

Total Knee Replacement

Total knee replacement is now arguably the most successful surgical procedure in orthopaedics. It produces a prosthetic joint that closely approximates normal anatomic functions and is relatively painless. More importantly, it restores quality of life and a return to regular activity… (read more)

Bilateral Knee Replacement

We offer bilateral knee replacement surgery for qualified candidates. Having both knees replaced on the same day is a good option for those who do not want to undergo the surgery and postoperative rehabilitation twice… (read more)

Computer Assisted Knee Replacement

We use computer navigation in over 95% of our knee replacements. Employing using a computer-assisted device during surgery has three potential advantages: less damaging to bone; greater accuracy; and there may be less blood loss… (read more)

Revision Knee Replacement

Joint replacement is one of the most common and successful procedures performed by orthopaedic surgeons, but not every procedure is successful. The goals of a joint replacement are to decrease or eliminate pain from an arthritic joint and improve mobility/joint function. Evaluation is warranted when a joint replacement is not achieving reducing or eliminating pain at the join… (read more)