If you’ve been diagnosed with knee osteoarthritis, you may be eligible for a minimally invasive surgery called a partial knee replacement.

A partial knee replacement, as the name suggests, only replaces part of a damaged knee. Unlike total knee replacement surgery, which replaces the entire knee joint with artificial implants, partial knee replacement preserves healthy tissue, allowing for a shorter recovery time and greater range of motion. 

Dr. Ira Guttentag, an orthopedic surgeon and sports medicine doctor at Florida Medical Clinic, regularly performs outpatient partial knee replacements for individuals with knee osteoarthritis so that they can get back to doing the activities they love without pain. In this blog, Dr. Guttentag answers five questions patients commonly ask about partial knee replacement so that you can decide if it’s right for you.

1. What is partial knee replacement? 

A partial knee replacement is a procedure that replaces part of the knee joint with an implant. The part of the knee that is replaced depends on which area, or compartment, is damaged. The knee has three primary compartments:

• Medial compartment (inside)
• Lateral compartment (outside)
• Patellofemoral compartment (front) 

Patients with only one damaged compartment and no severe complications may be candidates for partial knee replacement surgery. If more than one of these compartments is affected by osteoarthritis, a total knee replacement is typically recommended instead.

2. What type of implant is used?

The type of implant that’s used to replace the damaged part of the knee can affect the surgery’s long-term results. While most partial knee replacement implants are made from a combination of metal and plastic, some designs are more high-quality than others. 

Dr. Guttentag uses the Oxford® Partial Knee implant from Biomet Orthopedics for all partial knee replacement surgeries. This type of implant is the only mobile-bearing partial knee implant currently available in the US. Mobile-bearing implants, as opposed to traditional fixed-bearing implants, are able to rotate, which may provide patients with a greater range of motion.

Other benefits of the Oxford® Partial Knee implant include:

• Requires 75% less bone and cartilage to be removed, preserving natural knee function
• Faster surgery and recovery times 
• Less postoperative pain and scarring
• Longer survival rates

While more data is needed, mobile-bearing implants could also have a longer life expectancy than traditional implants due to less wear and tear being put on the moveable implant. 

3. Who is eligible? 

You may be eligible for partial knee replacement surgery if you: 

• Are suffering from osteoarthritis in just one part of the joint
• Have not found relief from non-surgical treatments, such as anti-inflammatory medications, bracing, and physical therapy
•  Are age 40 or older 
• Do not have severe arthritis or deformity of the joint 
• Do not have inflammatory arthritis, like rheumatoid arthritis

Even if you identify with all of the above, an orthopedic doctor will still need to examine your knee and make sure you are healthy enough for surgery. During a surgical consultation, Dr. Guttentag reviews the patient’s medical history and performs a physical evaluation to identify the location of the pain and determine the knee joint’s range of motion.

Medical imaging tests, like x-rays and MRIs, are also performed to give your surgeon a more accurate idea of the damage to determine if partial knee replacement is the best treatment option. With the Oxford® Partial Knee implant, your MRI is used to create a mold that attaches to your knee to help with sizing and alignment.

4. What is the recovery process like? 

Partial knee replacement can often be performed as an outpatient procedure, meaning that you can go home the same day. Higher-risk patients may need to stay overnight in a hospital. Either way, you’ll need to have someone who can assist you while you heal.

Because partial knee replacement surgery is less invasive, the recovery time is much shorter than a total knee replacement. Most patients are able to return to their normal activities after just four weeks, while total knee replacement patients can take up to 6 to 10 weeks.

The recovery process for a partial knee replacement includes:

• Pain management and wound healing. During the first two weeks after surgery, the main focus should be on pain management, swelling control, and range of motion. Your surgeon will give you specific instructions on when to take pain-relieving medications and how to ensure your wound heals properly.
• Physical therapy. A licensed physical therapist will show you how to do exercises to restore your knee’s range of motion and strength over the next several months. Therapy starts two days after surgery.
• Mobility aids. You’ll need to use a cane, walker, or crutches to help you get around safely for the first one or two weeks following replacement surgery.
• Follow-up exams. You’ll go back to see your orthopedic doctor several times after surgery to make sure the recovery process is going smoothly. The first post-op appointment is typically two days following surgery, so you will likely need someone to drive you there. Most patients can safely drive again anywhere from two to six weeks after surgery.

How quickly you recover from partial knee replacement surgery depends on a number of factors, including your age, weight, overall health, and how consistent you are with your physical therapy exercises. If you’re unsure if you can do a certain activity yet, such as riding a bike or going for a long walk, always ask your doctor. 

5. Are there any risks? 

As with any surgical procedure, there is always a minimal risk of infection, blood clots, or nerve damage. There is also the risk of requiring additional surgery in the future if your osteoarthritis spreads to other parts of the knee. In this case, total knee replacement may be needed. 

Dr. Guttentag will go over the risks with you in detail and answer any questions you may have during your preoperative medical assessment.

Learn More About Partial Knee Replacement Surgery

For many patients, partial knee replacement surgery allows them to live without pain and get back to doing the activities they enjoy—all with a much easier recovery than total knee replacement.  

If you think you may be a good candidate for partial knee replacement surgery, make an appointment with Dr. Ira Guttentag to learn whether or not the procedure is right for you. Even if you’re not a candidate, Dr. Guttentag will go over other treatment options with you so that you can start addressing the cause of your pain. Telehealth services are also available. 

About Dr. Ira Guttentag, MD, FACS

Dr. Ira Guttentag is an orthopedic surgeon at Florida Medical Clinic and has served as Head Team Physician for the Tampa Bay Lightning since 2002. He is an orthopedic consultant for the Toronto Raptors and Tampa Bay Buccaneers. One of the first doctors in Florida to perform outpatient, minimally invasive partial and total knee replacements, Dr. Guttentag takes pride in using the latest and most advanced orthopedic surgery techniques available.

Disclaimer: This blog is not intended to substitute professional medical advice. Every patient is different, so talk with your orthopedic doctor to learn what treatment options are best for you.