Total knee replacement (TKR) surgery can be a life-changing option for men and women suffering from the debilitating effects of advanced arthritis or other trauma to the knee joint.

Introduced in 1968, knee replacement surgery has advanced significantly during the past nearly five decades, relying on advancements in technology, materials and surgical techniques to offer millions of men and women greater mobility and improved range of motion so they can lead productive, fulfilling, pain-free lives once again.

Miriams Knee Replacement

Why performs TKR?

Total knee replacement replaces a joint that’s become damaged by the effects of arthritis, which causes the cartilage on joint surfaces to slowly wear away, revealing the unprotected ends of the bones underneath. Without this protective cartilage barrier, even the slightest movement can be painful, and everyday activities like walking, climbing stairs and even standing up can be excruciating.

Severe arthritis results in decreased mobility that can take a huge toll on your quality of life that may limit you to the amount and types of activities you can perform.

Total knee replacement helps you to enjoy more active lives because it replaces damaged joints so movement is more comfortable again.

Because it’s a major surgery, TKR is performed when other, more conservative options like medication, injections, and physical therapy have failed to provide relief or when they aren’t an option.

Judy Tactils Knee Replacement

Custom Knee Replacement

Custom knee replacements use MRI scans and x-rays to obtain precise measurements of your knee which can guide the surgeon during the knee replacement procedure. Data from the MRI and x-ray are fed into a computer, which uses special software to determine where the bone should be incised, or cut, in order to preserve as much healthy bone and ligament tissue as possible. This type of knee replacement offers patients substantial benefits over standard surgical techniques, including:

  • precise fit and alignment of the new joint
  • faster recovery
  • less blood loss
  • decreased risk of infection
  • less postoperative pain and discomfort
  • faster return to normal activities

How to perform TKR?

You will undergo physical exam and evaluation before surgery. You may require medical history and diagnostic imaging to ensure if replacement is the best option,

During the surgery, the knee joint will be carefully removed using the custom cutting guides to ensure as much healthy tissue is preserved as possible.

Hazel Atkinsons Story:

To facilitate movement, a metal joint is attached to the ends of the upper and lower leg bones and a special spacer is inserted. In some cases, the kneecap, or patella, will be resurfaced as well.

It takes about 1-2 hours to perform total knee replacement surgery under general anesthesia.

Conformis – iFit® Image to Implant Technology


The Conformis process starts with a patient CT scan through the hip, affected knee, and ankle. iFit® software converts the 2 dimensional CT data into a 3-dimensional model that replicates that patient’s unique and anatomical bone geometry.

In the 3D environment, iFit® recreates the patient’s natural J curves, corrected for deformity. It builds the femoral and tibial implants to match the unique size and shape of each knee. Further, it addresses common causes of patient dissatisfaction, pain, and unnatural feel.

Conformis has pioneered additive manufacturing and 3D printing technology for producing single-use, patient-specific. A patient uses positioning guide that comes pre-sterilized instead of reusable instruments that require cleaning and re-sterilization.

IFit® design and manufacturing technology enables mass-customization, a term foreign to the orthopedic industry. It customizes implants and instruments are delivered pre-sterilized unlike any knee replacement available today.

Simply put, iFit® technology put Conformis in a class of its own with an unparalleled speed of innovation, and our source for Conformis is Empire Surgical Solutions right here in New York.

Conformis – iFit® iTotal G2


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Dr. Nakul Karkare


What are the different types of knee replacement surgery?

Knee replacement surgery entails removing the diseased part of the damaged knee joint and capping it with an artificial part. The knee joint has three compartments called medial (inside of the knee), lateral (outside of the knee) and patellofemoral (underneath the knee cap) compartments. Total knee replacement is the most common type of knee replacement that involves replacing the all three compartments.

Partial knee replacement involves replacing only part of the joint-the medial, lateral or patellofemoral joint. It is imperative to be selective in choosing which knees are good candidates for partial replacements because poor selection is responsible for early failures. If there is an excessive deformity or if there is significant arthritis in other compartments, partial knee replacement does not result in good pain relief and may necessitate revision to a full knee replacement.

What conditions require knee replacement?

Knee replacement is the last option for treating pain from arthritis. Arthritis means that the cartilage (the glistening tissue at the end of the bone) has worn out and the bone is rubbing on bone. There are numerous conditions that can cause this and there are more than a hundred types of arthritis. The most common types are osteoarthritis and rheumatoid arthritis. Orthopedic surgeons typically try a variety of injections in the joint and physical therapy before knee replacement surgery.

How to prepare for knee replacement?

The treating orthopedic surgeon coordinates care in preparation for knee replacement surgery. There are established protocols before any joint replacement surgery that involve medical clearance, dental clearance, nasal cultures, cardiac, urine and blood tests etc. It is very important to select a surgeon who specializes in joints and a hospital that does a large number of joints. Literature has shown that larger volume a surgeon and hospital performs, better are the outcomes.

How long does the surgery last?

Surgery lasts about an hour to one and half hour depending on the complexity of the case. There are many steps involved in the operating room before surgery like anesthesia, prepping and draping the knee etc. Therefore by the time the patient is wheeled into the operating room to the time patient comes out of the post-operative care unit, the time maybe more than two hours.

Most patients walk full weight bearing on the same day of surgery with a walker. Most patient with partial knee replacements go home the same day. Majority of total knee replacement surgery patients go home the next day. Fewer patients are going to inpatient rehabilitation facilities.

How much pain is involved after? And how can that be managed?

We have made major advances in pain management in the post-operative period. We stay ahead of the pain by giving pain medication on a scheduled basis. Pain medication is even given before the patient is wheeled into the operating room. We use a combination of narcotic and anti-inflammatory medications orally, intramuscularly and intravenously. Additionally, we inject the joint and the tissues around it intraoperatively with anesthetic with lasts for about two days.

How long is the recovery?

The total rehabilitation after total knee replacement is about three months. Recovery after a hip replacement is very different where patients are pain free within days. After total knee replacement surgery, patients see light at the end of the tunnel at 4 to 6 weeks and at 3 months they are significantly better. Improvements continue for several months afterwards but the range of motion that exists at 3 months is what remains for life which is why rehabilitation and physical therapy is extremely important after total knee replacement surgery.

What restrictions on activities are there at each stage of recovery?

Patient can walk with full weight immediately after knee replacement surgery. They should range their knee in the post-operative period and do physical therapy to decrease the possibility of stiffness. In the long term, it’s advisable not to do any impact type of activities. Artificial joints have no ability to heal themselves and impact increases the possibility of loosening.

What does the recovery involve?

After having full knee replacement surgery, most patients go home the next day. A visiting nurse and physical therapist that visits them at home. Patients then do outpatient physical therapy three times a week for next several weeks. Most patients are pain free in 3 months after the surgery.

How much physical therapy is involved after?

Physical therapy start immediately after surgery and is required for about three months after surgery. Physical therapy starts in the hospital, then at home and then in an outpatient facility. It helps in improving range of motion, improving strength, decreasing inflammation and pain.

What are the best case scenario results?

Knee replacement surgery is done for pain and most patients are completely pain free after the surgery. Along with hip replacement surgery, it is one of the most satisfying surgeries in orthopedics. Some patients have trouble swatting and kneeling. Occasionally they may have clicking in the joint but their quality of like has improved substantially after surgery.

When and why do some knee replacements fail?

More than 90% of knee replacements last for more than 20 years. Most early failures are due to infection that may happen within few months of the surgery. Most late failures are due to loosening that happens over several years. Intermediate failures may happen because of suboptimal alignment and patient factors that include impact activities to the joint.

How long does it take to know if your knee replacement was successful?

The arthritis pain is gone immediately after the surgery. Patients immediately notice this when they place weight over the operated extremity. The surgical pain gets better with time. Most pain is gone in three months. Infection or other adverse events manifest as increasing pain, redness, swelling etc. A knee is not improving after surgery warrants further evaluation by a joint replacement surgeon.

Are follow-up surgeries (that aren't a total re-do) ever needed (say, for scar tissue), and why?

The idea of knee replacement surgery is to give the patient one operation that will last a lifetime. Follow up surgery after knee replacement will only be needed if there is a complication. Occasionally, if the knee is not progressing for range of motion with physical therapy, the knee may need to be manipulated under anesthesia to break the scar tissue. If there is an infection surgery maybe need to clean up the joint.

How long does a knee replacement last?

More than 90% of full knee replacements last for more than 20 years. Partial knee replacements may not last long if the indications are not accurate. There is growing literature to show that if the selection is correct for doing partial knee replacements and if the surgery is done in an accurate manner to insure correct alignment, the long term results may be similar to a full knee replacement.

How best to take care of one's knee following knee replacement?

Patients have an active pain free life after knee replacement. They can play golf, swim, do horseback riding, ski etc. Its prudent to avoid constant impact type of activity. Some of the worst long term outcomes are in active males who abuse their joints. Additionally, it’s imperative to take antibiotics when patients visit the dentist because bacteria can travel from the mouth to the knee through the blood and cause infection in the knee joint.

How to AVOID knee replacement.?

Arthritis leading to knee replacing is a combination of genetic and environmental factors. Modifiable factors include maintaining body weight and musculature around the joint. Patients suffering from rheumatological disorders should be diligent in taking medication. We are going significantly less joint replacement surgery for rheumatoid arthritis because of better drugs that have come out in the past few decades. Surgery can be done for deformities of the knee like bow leggedness to dramatically decrease the need for knee replacement surgery in the future.

Are you a good candidate for TKR surgery?

Total knee replacements can be a good option for many men and women, but they’re not for everyone.

Are you in pain?

Have you had a prior knee surgery?

Do you have injured ligaments?

If not, then you could be a good candidate for a complete knee replacement.


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