Partial Knee Replacement

Partial knee replacement has been around as a surgical option for more than 30 years. The ZUK implant builds on this foundation and has been helping people who only have damage on one side - or compartment - of their knee since its introduction in 2004. Unlike many other partial - and total - knee implants, the ZUK implant is designed to allow for high flexion of the knee. Flexion is the extent to which the knee is capable of bending. While the ZUK implant cannot guarantee you high-flexion, it has been designed to accommodate up to 155° of flexion if you are able to achieve it. The ZUK partial knee was designed for placement using today's minimally invasive techniques. If you are a candidate, minimally invasive surgery may help you get back to life and work faster than you would if you underwent traditional knee replacement surgery. For more information on minimally invasive knee surgery, please visit


Potential Benefits Of Partial Knee Replacement Compared with Total Knee Replacement

(Results may vary)

  1. No disruption of the knee cap1
  2. Less blood loss2
  3. Possibility for less post-operative pain2
  4. Faster rehab/recovery time2
  5. Better range of motion3

1Based on ZUK surgical technique
3 Laurencin CT, Zelicof SB, Scott RD, Ewald FC. Unicompartmental versus total knee arthroplasty in the same patient. A comparative study. Clin Orthop Relat Res. 1991; (273):151-156

Description of the ZUK Partial Knee Implant Procedure

The invasive procedure allows your surgeon to access, remove and accurately replace only the damaged surface of the knee, leaving your healthy bone intact. Below is a brief description of the procedure:

  1. An incision is made to expose the damaged joint
  2. The end of the femur and top of the tibia are shaped to accommodate the ZUK Partial Knee components
  3. Trial components are placed to ensure proper alignment
  4. Once properly aligned, the trial components are removed
  5. The femoral and tibial ZUK Partial Knee UNI components are implanted
  6. The incision is closed.

Post-Operative Protocol

After leaving the operating room, you will be transported to recovery where you will be closely monitored. Once you have recovered from surgery and your surgeon has given approval, you will begin the post-operative rehabilitation process.

Your surgeon may recommend the following to begin rehabilitation while you are still in the outpatient surgery center or hospital:

  1. Ice and elevation to reduce pain and swelling in your knee
  2. A continuous passive motion machine that will promote the return of your knee's range of motion
  3. Walking with a walker or crutches
  4. Instruction in your home exercise program which may include the exercises shown on the following pages

What To Expect:

  • On average, this type of surgery takes approximately one to three hours, depending on your individual circumstances.
  • Usually you'll be in recovery for one to three hours after surgery.
  • After surgery, your pain will be managed via intravenous therapy and/or a pain pump and/or injection and/or pills given by mouth.
  • Depending on your situation, you will probably be able to walk with the aid of a walker or cane the day of or day after surgery.
  • It is normal for your joint to remain warm, swollen and slightly tender for a number of weeks. Call your doctor immediately, however, if you notice:
    • Increased pain, redness or swelling
    • Incision drainage
    • Prolonged nausea or vomiting
    • Chest pain or shortness of breath
    • Tenderness in the calf or thigh of the operated leg
    • A fever
  • Most patients are ready to drive a car about eight weeks after surgery, but not unless your surgeon authorizes it.
  • Recovery varies greatly based on individual factors but most patients resume normal activities in about 12 weeks following surgery.

Important: Not all patients are candidates for the ZUK Partial Knee Implant. Discuss your condition and implant options with your surgeon. Individual results of joint replacement vary. Implants may not produce the same feel or function as your original knee. There are potential risks to knee replacement surgery such as loosening, fracture, dislocation, wear and infection that may result in the need for additional surgery. Longevity of implants depends on many factors, such as types of activities and weight. Do not perform high impact activities such as running and jumping unless your surgeons tells you these activities are acceptable. Early device failure, breakage or loosening may occur if you do not follow your surgeon's limitations on activity level. Early failure can happen if you do not guard your knee joint from overloading due to activity level, failure to control body weight or accidents such as falls. Talk to your doctor to determine what treatment may be best for you. For additional information on these risks, talk to your surgeon.

The information in this booklet is for informational and educational purposes only and is not meant as medical advice. Every patient's case is unique and each patient should follow his or her doctor's specific instructions. Please discuss nutrition, medication and treatment options with your doctor to make sure you are getting the proper care for your particular situation.

All information provided on this website is for information purposes only. Every patient's case is unique and each patient should follow his or her doctor's specific instructions. Please discuss nutrition, medication and treatment options with your doctor to make sure you are getting the proper care for your particular situation. If you are seeking this information in an emergency situation, please call 911 and seek emergency help.

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