Knee pain can interfere with everything from walking to exercise and make it harder to stay active. When conservative treatments stop working, total knee replacement may be a worthwhile option.
Dr. Alexander S. McLawhorn is a hip and knee specialist at the Hospital for Special Surgery. He offers expert joint replacement care in New York City and Stamford, Connecticut. With his experience in the latest surgical techniques and procedures, he can help you get back to your favorite activities.
What Is Total Knee Replacement?
Total knee replacement (TKR), also known as total knee arthroplasty, is a surgical reconstruction of the knee joint using prosthetic implants made of special metals, plastic, and/or ceramic-coated metal.
Total knee replacement surgery is commonly performed in order to repair a knee joint suffering from damaged cartilage and/or bone, usually as a result of knee arthritis. It can be thought of as a resurfacing procedure of the knee.
The damaged cartilage and bone are removed, and the ends of the bones comprising the knee are resurfaced with metal. A plastic insert is placed between the metal components to provide long-lasting, low-friction motion.
Why Is Total Knee Replacement Performed?
Total knee replacement surgery is generally performed when there is a substantial amount of damage to the cartilage in the knee, and when you are suffering from a significant amount of knee pain. The function of the knee is reduced both because of pain and also because of joint damage and deformity.
The surgery may be recommended if you are experiencing the following symptoms:
- Recurring severe knee stiffness or pain
- Knee pain that lasts throughout the day and night, even when resting
- Knee pain that has not responded well to nonsurgical treatments
- Trouble performing normal activities due to debilitating knee pain
- Knee arthritis that has spread to more than one area of the knee
How Do I Decide When I Need a Knee Replacement?
Choosing to have a knee replacement surgery is a personal decision that is made together with Dr. McLawhorn. Your preference for surgery, your lifestyle demands, and your expectations for outcomes after surgery aid the decision-making process and will guide your choice between nonsurgical care and knee surgery.
In general, when knee pain begins to interfere with your daily life, prevents you from participating in your recreational activities, wakes you from sleep, and/or requires prescription pain medication, knee replacement surgery is a consideration.
Dr. McLawhorn recommends considering total knee replacement when the following criteria are met:
- Severe bone-on-bone arthritis on an X-ray (not MRI, CT, or otherwise), affecting the joint space between the thigh bone (femur) and the shin bone (tibia).
- Severe pain, stiffness, and dysfunction of the knee as measured using standardized knee questionnaires (such as the KOOS JR)
- Failure of nonsurgical treatments, especially weight loss, physical therapy, and non-steroidal anti-inflammatory medications.
- Knee pain that severely impairs walking and everyday activities.
Be prepared to be fully engaged in your recovery. No one else can heal your knee for you. Recovery will require at least three months of personal dedication to daily exercises and intermittent physical therapy sessions (two to three times per week). Full recovery takes at least one year to achieve the full benefits of the knee replacement.
You should also understand that knee replacement does not restore a "normal knee". TKR is a mechanical device that has limitations. You may experience clicking from the metal and plastic parts, and experience numbness in the skin on the outside of the knee. Kneeling may feel funny or painful, and it is not guaranteed that you will be able to kneel after TKR.
A persistent sensation of stiffness and/or band-like sensation across the front of the knee is common. Mild pain with certain activities is also common. Running and impact activities are discouraged, as these activities will hasten the failure of TKR.
What Are the Goals for Total Knee Replacement Surgery?
First and foremost, the purpose of total knee replacement surgery is to improve pain. Other general goals are:
- Improve knee function
- Provide a stable, well-aligned knee
- Prevent excessive wear of the implanted components
- Avoid complications
How Long Will a Total Knee Replacement Last?
Current clinical data indicates that both hip and knee prosthetic joints typically have an annual failure rate ranging from 0.5% to 1.0%. This translates to a roughly 90–95% probability that the joint will still be functioning at 10 years, and approximately an 80–85% chance at the 20-year mark. Ongoing improvements in implant materials and surgical methods may further extend these outcomes.
What Does Total Knee Replacement Surgery Involve?
A total knee replacement procedure will be customized depending on the individual needs of each patient, and the specific steps involved in the surgery may vary from person to person.
However, in most cases, you can expect the following:
- Regional anesthesia is provided with either a spinal or epidural to numb your body from the waist down; sedation through an IV will allow you to sleep throughout the surgery.
- One or more nerve blocks (injections around sensory nerves) will be given to lessen postoperative pain.
- Antibiotics are given prior to surgery to prevent infection.
- An incision is made at the front of the knee so Dr. McLawhorn can reach the joint. The opening is usually about five to seven inches long, which allows precise placement of the implants.
- The menisci are removed. In most cases, the anterior cruciate ligament (ACL) is removed. Depending on the total knee replacement design, the posterior cruciate ligament (PCL) may or may not be removed.
- Damaged cartilage and bone are removed.
- The ends of the femur and tibia bones are resurfaced with metal components
- A highly cross-linked polyethylene (plastic) liner is inserted between these components, and a plastic “button” is used to resurface the backside of the patella (kneecap); these provide smooth motion to the joint.
- The soft tissues are closed over the implants.
What Are the Advantages of Total Knee Replacement?
There are many benefits to undergoing total knee replacement surgery, including:
- Alleviation of knee pain
- Restoration of mobility in the knee
- Being able to return to most normal physical activities
What Can I Expect After Total Knee Replacement?
Immediately after surgery, you will be able to walk on your operated knee. A walker, crutches, or a cane may be used for several weeks, if needed. Depending on the demands of your job, you may return to work within two weeks of surgery. Return to normal activity, including heavy labor and sports, can occur at six months after surgery. Full recovery after total knee replacement can take up to one year for some patients.
Dr. McLawhorn recommends routine follow-up of all his knee replacement patients. In general, patients will be evaluated at six weeks, 12 weeks, one year, two years, five years, and then every five years after surgery. A clinical examination and X-rays will be performed at some of these visits.
Learn more about what you can expect before and after surgery in Dr. McLawhorn’s FAQs.
Why Choose Dr. Alexander McLawhorn?
Expertise makes a difference in knee replacement surgery. Dr. Alexander S. McLawhorn performs over 600 joint replacements each year using advanced techniques to improve recovery and long-term results. As a specialist at Hospital for Special Surgery, he provides high-quality care in New York City and Stamford, CT.
Dr. McLawhorn is the Director of Research and Innovation at HSS, which means he’s always at the forefront of surgical advancements. He is recognized nationally and always brings the latest technology and research into every procedure. If you’re looking to get the best possible outcome from surgery, Dr. McLawhorn is a trusted choice.
How to Prepare for Knee Replacement Surgery
We often advise patients to do the following to prepare for knee replacement surgery:
- Strengthen the knee: Exercises to improve muscle strength and flexibility can aid recovery.
- Manage medications: Certain medications, such as blood thinners, may need to be adjusted before surgery.
- Plan for mobility assistance: Arrange for a walker, crutches, or a cane to help during the initial recovery phase.
- Prepare the home: Remove trip hazards, set up a comfortable rest area, and install handrails for your safety.
- Follow preoperative instructions: This may include fasting, showering with antibacterial soap, and arranging transportation for the day of surgery.
What Is the Difference Between Total and Partial Knee Replacement?
Total knee replacement involves replacing all three compartments of the knee joint – the medial (inside), lateral (outside), and patellofemoral (front). It is typically recommended for patients with advanced arthritis affecting most of the knee.
Partial knee replacement, also known as unicompartmental knee replacement, replaces only the damaged portion of the knee while preserving healthy bone and ligaments. This option is typically suitable if you have arthritis that’s confined to one area of the knee. Recovery from a partial knee replacement is often quicker than total knee replacement, but not all patients are candidates.
Am I Too Young or Too Old for Knee Replacement?
There is no strict age limit for knee replacement, but the decision depends on factors like pain severity, joint damage, and overall health.
- Younger patients (under 50): Knee replacement may be considered if pain and mobility issues impact your quality of life, though surgeons may explore nonsurgical treatments first. Younger patients may require a revision surgery later in life due to implant wear over time.
- Older patients (70s and beyond): Age alone is not a barrier to surgery. If a patient is in good health and can tolerate surgery and rehabilitation, knee replacement can be a safe option.
Can I Go Up and Down Stairs Soon After Surgery?
You may be able to start using stairs within the first few days after surgery, but this depends on your strength, balance, and pain levels. At first, you may need assistance, and/or you should use a railing for support.
Physical therapy includes stair training. Many patients can navigate stairs more independently within a few weeks, though it may take several months to feel fully confident again.
Can Both Knees Be Replaced at the Same Time?
Yes, both knees can be replaced during a single surgery, which is called a bilateral knee replacement. This approach may be recommended if arthritis affects both knees severely and limits mobility. The benefit is undergoing one surgery and one recovery period instead of two.
However, recovery can be more demanding, and not everyone is a candidate. Your overall health, fitness level, and ability to participate in rehabilitation help determine whether this option is safe.
How Much Pain Should I Expect After Surgery, and How Is It Managed?
Some pain and stiffness are expected in the days and weeks after knee replacement surgery. Most patients describe it as manageable and improving steadily with time. Pain is typically controlled with a combination of medications, including anti-inflammatories, nerve blocks, and sometimes short-term prescription pain medicine. Ice, elevation, and physical therapy also play important roles in reducing discomfort and supporting recovery.
How Soon Can I Drive After Knee Replacement Surgery?
The timing depends on which knee was operated on and how quickly strength and reflexes return.
For a left knee replacement, many patients can drive within two to three weeks if they drive an automatic car. For a right knee replacement, it may take four to six weeks, since the right leg controls the pedals.
You should only drive when you are no longer taking narcotic pain medication and feel confident in your ability to brake quickly and safely.
What Are the Signs That Something May Be Wrong With My Knee Replacement?
Explore Your Knee Replacement Options With Dr. McLawhorn
If you are suffering from debilitating knee pain or knee arthritis and exploring total knee replacement as a treatment option, it is important to seek advice from an orthopedic knee specialist to accurately diagnose and treat your condition. Dr. McLawhorn is a hip and knee specialist at Hospital for Special Surgery serving patients in New York and Stamford, Connecticut.
To learn more, call 203-705-2113 (CT) / 212-606-1065 (NYC) today or schedule an appointment by using the form on this page.
