Total Knee Arthroplasty

A new knee gives most people their walk back. Knowing what to expect is what makes them glad they did it.

In a Danish randomized trial published in the New England Journal of Medicine, knee replacement followed by physiotherapy doubled the improvement in pain and function at one year compared with physiotherapy, education and painkillers alone.

Is it time for a new knee?

Nobody needs a knee replacement because of an X-ray. The decision belongs to the person living with the knee. It turns on pain that limits walking, stairs and sleep despite months of exercise, weight loss where it applies, painkillers and perhaps an injection, on an X-ray or MRI that shows advanced arthritis with the joint space narrowed or gone, and on a body fit enough for an operation and willing to do the rehabilitation afterward, which matters as much as the surgery itself. Age carries less weight. People from their fifties to their late eighties do well, though a younger, very active patient will more likely need a second operation decades later. A surgeon who reviews your X-rays taken standing, your list of medicines and your other illnesses can tell you whether the knee and the rest of you are ready.

Expectations decide satisfaction. In an Ontario study of 1,703 knee replacements, unmet expectations raised the risk of being dissatisfied more than tenfold.

What the operation achieves, in numbers

The strongest evidence comes from a Danish trial.

This table scrolls sideways on a narrow screen. Swipe or drag to see every column.

Two other findings from the Danish trial matter. Most patients assigned to exercise, education and painkillers alone had still not chosen surgery a year later, and those who did have the operation gained far more, which supports the order most surgeons follow, a serious trial of treatment without surgery first and then the operation when that has run its course.

Total or partial knee replacement

Arthritis confined to the inner half of the knee can be treated by replacing that half alone. The TOPKAT trial, published in the Lancet in 2019, randomly assigned 528 patients in 27 British hospitals with arthritis limited to the inner compartment to a partial or a total replacement. Five years on, the knee scores matched. Complications and reoperations were similar too, and the partial replacement cost less and gave slightly more quality of life, so the authors recommended it as the first choice for that pattern of arthritis, while registries show the other side, with partial replacements wearing out sooner, 70 percent still in place at 25 years against 82 percent for total replacements in the Lancet review. Partial replacement leaves the healthy cartilage and both cruciate ligaments in place, which many patients notice as a more natural-feeling knee. Wider damage changes the answer. A knee with arthritis in more than one compartment, a damaged ligament or marked deformity needs the total replacement, and so does a knee with rheumatoid arthritis.

Robotic assistance

Several Istanbul hospitals advertise robot-assisted knee replacement, most often with Stryker's Mako system, which plans the bone cuts from a CT scan and limits the saw to the planned area. The implant then sits closer to the plan. Whether that becomes a knee that feels better or lasts longer for the average patient remains under study. Experience counts for more than the machine.

1. A CT scan before surgery. The system builds a three-dimensional model of your knee.
2. A plan for each cut. The surgeon sets implant size, position and alignment on the model.
3. Boundaries in theater. The robotic arm stops the saw at the planned limits.
4. A balance check. The surgeon measures the gaps in the bent and straight knee before the final implant goes in.

Inside the new knee

• The femoral component. A curved metal cap, usually cobalt-chromium, over the end of the thigh bone.
• The tibial component. A flat metal tray on top of the shin bone.
• The insert. A highly cross-linked polyethylene spacer between the two, which takes the wear.
• The patellar button. A plastic surface on the back of the kneecap, used by some surgeons in every knee and by others only when the kneecap has worn.

Bone cement, which sets within minutes, fixes most components, and some are designed for bone to grow into them instead. Published packages in Istanbul name implants from the large international makers, among them Stryker, Smith and Nephew and Zimmer Biomet. Get the implant name and model in writing. A surgeon at home will need it if the knee ever needs attention.

The operation and the days on the ward

On a phone, swipe the table sideways to read every column.

Risks, with what is done about each

Serious problems are uncommon. Still, the Danish trial recorded four times as many serious adverse events with surgery as without it, so the decision deserves time.

Recovery week by week

On a phone, swipe the table sideways to read every column.

Kneeling stays uncomfortable for many people, and running and jumping sports are best given up for walking, cycling, swimming and golf.

How long to stay in Istanbul

Ten to fourteen days covers the trip for most people. Published packages agree on that window, with three to seven of those nights in hospital and the rest in a hotel close by, where outpatient physiotherapy continues and the wound gets checked before the flight.

Flying home

The surgeon issues a fit-to-fly letter once the wound is dry, walking is safe on crutches and clot prevention is in place, usually ten to fourteen days after surgery. Four habits keep the long flight safe.

Both knees in one trip?

Replacing both knees under one anesthetic is possible for fit patients with arthritis in both knees, and it means one anesthetic, one recovery and one trip, at the cost of a harder first two weeks and a higher risk of heart and clot complications than a single knee. Many surgeons prefer a different plan for patients over 75 or with heart or lung disease. Two operations a few days apart in the same admission is one option. Two trips months apart is another. Your health decides this, never the travel plan.

What decides the cost

One knee or two sets the largest difference. The implant model, a robot-assisted operation, the number of hospital nights, the physiotherapy sessions in Istanbul and the hotel nights before and after each move the total. Your own health moves it as well, and this is the part a published package cannot know. Diabetes that needs tighter control before surgery, heart disease that calls for a cardiology review and an echocardiogram, a body mass index high enough to lengthen the operation, blood thinners that have to be stopped and bridged, anemia that needs treating first, and a previous operation on the same knee with old scars and metalwork all add tests, sometimes an extra night or two, and occasionally a different implant. With your X-rays and your medicine list in hand, a surgeon can say in advance which of these apply, and the figure you receive then reflects your knee rather than an average one.

Published Istanbul packages list the surgeon and anesthesia fees, the implant, preoperative tests and X-rays, the hospital nights, physiotherapy sessions, airport transfers, an interpreter and, in some, hotel nights. Crutches, medicines after discharge, flights and extra nights sit outside many of them.

A quote you can compare names the implant model, counts the hospital nights and physiotherapy sessions, and says whether a hotel, crutches and medicines sit inside it. That figure comes only from a surgeon who has seen your X-rays taken standing. The review costs nothing.

Arranging the trip

A coordinator answers your first WhatsApp message and stays with you to discharge. The number still works after you fly home. The team speaks English, Arabic, French, Russian, Serbian, Romanian and Spanish, arranges interpreters for other languages, and puts a companion bed in your room so one person can stay throughout the admission, while the international patients office books the hotel for the nights either side and sends the invitation letter for a medical visa about ten days before travel. Transfers are arranged. Halal, vegetarian and diabetic meals come from the hospital kitchen, a prayer room sits on site, and a request for a female physician goes to the department with your first message.

Pack loose trousers and flat shoes with a back.

Bring your current medicines in their boxes.

Once you are back home

Exercises continue for at least three months. A physiotherapist at home helps in the first weeks. A review at six weeks, by video with the Istanbul surgeon or in person with a local orthopedic surgeon, checks the bend and the wound, and an X-ray at one year confirms the implant is settled. Tell any dentist or doctor treating an infection that you have a joint replacement.

A red, hot, swollen knee with fever, a wound that leaks after the first week, calf pain or breathlessness. Each needs a doctor the same day. A local emergency department sees you first, using the English discharge file with the implant details, and the coordinator relays the details to the surgeon who operated.

Total knee arthroplasty FAQ