Knee replacement: what to expect before, during and after surgery

A knee replacement, or knee arthroplasty, removes the worn surfaces of a damaged knee joint and replaces them with metal and plastic components. It is one of the most reliable operations in orthopaedics for pain that no longer responds to anything else — but it is still major surgery, and the result depends as much on the months of rehabilitation that follow as on the hours in theatre. This page explains what the operation involves and what recovery realistically looks like.

When is a knee replacement considered?

Surgery is discussed only after non-surgical treatment has been tried and has stopped working. The decision is based on how the knee affects your daily life, not on the X-ray alone. The signs that usually bring people to this point are:

• Pain at rest and at night, not only when walking
• A walking distance that keeps getting shorter
• Difficulty with stairs, getting out of a chair, or getting in and out of a car
• Bowing or knock-knee deformity of the leg axis
• Painkillers, injections, weight management and physiotherapy no longer helping

Two people with identical X-rays may need completely different advice. Your age, weight, other medical conditions, activity level and what you expect from the knee are all part of the discussion.

What the operation involves

The damaged cartilage and a thin layer of bone are removed from the end of the thigh bone and the top of the shin bone, and replaced with implants that recreate the joint surface. The ligaments that stabilise the knee are balanced so that the joint moves evenly through its range. Most people have spinal anaesthesia with sedation rather than a general anaesthetic, and stay in hospital for approximately three to five days.

Does robotic assistance change the operation?

At Medinova the operation is performed with the ROSA® Knee System. It is worth being precise about what this does. The robot does not operate by itself and it does not make the decision for you: it builds a three-dimensional plan of your knee, guides the bone cuts to that plan during surgery, and measures ligament balance as the knee is moved. The aim is a more accurately positioned implant, and accurate positioning is one of the factors associated with how well a knee replacement functions and how long it lasts.

What robotic assistance does not do is turn an unsuitable candidate into a suitable one, remove the need for rehabilitation, or change the risks listed below. If you are told anywhere that robotic surgery is painless or risk-free, that is marketing, not medicine. How robotic-assisted knee replacement works →

Preparing for surgery

• Medical assessment. Blood tests, an ECG and, where needed, cardiology or chest review.
• Dental and skin checks. An untreated dental abscess or a skin infection is a source of bacteria that can settle on a new implant, so these are treated first.
• Medication review. Blood thinners, some rheumatology drugs and certain diabetes medicines need to be adjusted before the operation.
• Stopping smoking. Smoking measurably slows wound healing and increases the risk of infection. Even a few weeks without cigarettes before surgery helps.
• Preparing your home. Loose rugs removed, a firm chair with armrests, a handrail on the stairs, and someone who can help for the first two weeks.

Recovery — a realistic timeline

• Day 0–1. You stand and take your first steps with a frame or crutches, usually on the day of surgery or the morning after. Early movement is what prevents blood clots and stiffness.
• Week 1–2. Home with crutches, regular ice and elevation, and daily exercises. Pain and swelling are at their most demanding here. Stitches or clips come out around day 10–14.
• Week 3–6. Most people walk indoors without crutches and can manage stairs one step at a time. Bending typically reaches 90–120 degrees. Driving becomes possible when you can brake safely and are off strong painkillers — usually around six weeks.
• Month 3. Desk work, swimming and cycling are usually comfortable. Swelling in the evening is still normal.
• Month 6–12. Continued gradual improvement. Some swelling, numbness around the scar and a feeling of warmth in the knee can persist for a year, and this is expected rather than a complication.

Physiotherapy is not optional. The range of movement you gain in the first six weeks is largely the range you keep.

Risks and complications

Serious complications after knee replacement are uncommon, but they are not zero, and any surgeon who tells you otherwise is not being straight with you. The recognised risks include:

• Infection of the wound or, rarely, of the implant itself — the latter can require further surgery
• Blood clots in the leg or lung, which is why blood-thinning treatment and early walking are used
• Stiffness, sometimes needing a manipulation under anaesthetic
• Bleeding, or a haematoma around the joint
• Injury to nerves or blood vessels, and a permanent patch of numbness beside the scar, which is common
• Persistent pain in a minority of patients despite a technically correct operation
• Loosening or wear of the implant over time; most modern knee implants are expected to last 15–20 years or more, but a revision operation may eventually be needed, particularly in younger and more active patients

Your own risk depends on your age, weight, diabetes control, smoking and other conditions. Ask your surgeon to explain your individual risk rather than the average.

What a knee replacement will not do

• It will not give you the knee you had at twenty.
• Kneeling directly on the operated knee is uncomfortable for many people, permanently.
• Running, jumping and contact sports are not recommended afterwards; walking, swimming, cycling and golf are.
• It does not treat pain that is coming from your hip or your lower back, which is why the examination looks beyond the knee.

Questions worth asking your surgeon

• Is my knee damage advanced enough that surgery is the right step now?
• Would a partial replacement or an osteotomy be an option in my case?
• What is your plan if I have a complication after I return home?
• What should my knee be able to do at six weeks, and at six months?
• How many of these operations do you perform, and what implant will you use?

If you are travelling from abroad, ask specifically how long you need to stay in Türkiye, when you will be fit to fly, and who supervises your physiotherapy once you are home. These answers should be given before you book anything.

Knee replacement at Medinova is performed within our Orthopaedics & Traumatology department by Prof. Dr. İlhan Özkan and Prof. Dr. Ş. Öner Şavk, and the department also offers robotic-assisted knee replacement. The rehabilitation that follows is planned together with our Physical Therapy & Rehabilitation department.