The main goal of knee replacement is to reduce pain caused by advanced joint damage and make walking, stairs and daily activities easier.

Advanced arthritis on X-rays is important; however, the decision for surgery should also consider pain, movement limitation, walking capacity, knee deformity and patient expectations.

A successful knee replacement process depends not only on surgery, but also on postoperative knee range of motion, muscle strength, gait training and regular rehabilitation.

Age, bone quality, knee deformity, ligament balance, range of motion, general health condition and activity expectations may affect surgical planning and implant selection.

Advanced damage in the knee joint often presents with knee pain, difficulty walking, difficulty going up or down stairs and limited range of motion. Some patients may also experience deformity, bowing of the legs, sounds from the knee, catching sensation or a feeling that the knee does not feel secure.

Findings that may require knee replacement evaluation include:

• Long-lasting knee pain

• Pain that increases while walking

• Significant decrease in walking distance

• Difficulty going up or down stairs

• Pain while sitting down or standing up

• Serious difficulty kneeling or squatting

• Decreased knee range of motion

• Inability to fully bend or fully straighten the knee

• Night pain

• Knee swelling

• Bow-legged or knock-kneed deformity

• Limping

• Giving-way, catching or insecurity sensation in the knee

• Significant limitation in daily activities

• No sufficient relief despite pain medication or supportive treatments

The presence of these symptoms alone does not automatically mean that surgery is needed. However, if pain, deformity and limited motion significantly affect quality of life, the knee joint should be evaluated in detail.

No. Pain felt around the knee may arise from the lower back, hip, nerve compression, muscle-tendon problems, meniscus injuries, ligament injuries or inflammatory diseases. Therefore, before deciding on knee replacement, it is important to evaluate whether the pain truly comes from advanced damage in the knee joint through physical examination and imaging.

Knee replacement is a surgery that aims to replace severely damaged knee joint surfaces with artificial joint components. The knee joint consists of the joint surfaces between the thigh bone, shin bone and kneecap. When the cartilage and bone tissue on these surfaces are severely damaged, pain, limited motion, deformity and difficulty walking may occur.

In total knee replacement, the damaged joint surfaces on the thigh bone and shin bone are usually prepared, and artificial surfaces made of metal and special polyethylene components are placed. In some patients, the joint surface behind the kneecap is also evaluated and may be replaced if needed.

Knee replacement is most commonly performed for advanced knee arthritis. However, it may also be needed due to inflammatory joint diseases, post-traumatic joint damage, previous fractures, severe leg deformity, ligament imbalance or certain diseases that damage the joint surface.

The decision for knee replacement should not be made only because arthritis is seen on X-rays. The patient’s pain, walking distance, stair function, knee range of motion, leg alignment, physical examination findings, associated hip-lower back problems and imaging results should be evaluated together.

No. Knee replacement aims to reduce pain, improve leg alignment and increase function by replacing damaged joint surfaces with artificial surfaces. After a successful surgery, many patients experience significant relief in daily activities; however, a prosthesis is not a natural knee joint. Therefore, range of motion, muscle strength, implant longevity, infection risk, loosening risk and long-term follow-up are important.

Knee replacement may be performed when the damage in the knee joint has reached an advanced stage and significantly affects the patient’s quality of life. The most important factor is not the X-ray alone, but the patient’s pain and loss of function.

Knee replacement may be considered in patients with:

• Advanced knee arthritis

• Markedly decreased walking distance due to knee pain

• Difficulty going up or down stairs, sitting and standing or doing daily tasks

• Night pain or pain at rest

• No sufficient relief despite non-surgical treatments

• Markedly restricted knee range of motion

• Severe bow-legged or knock-kneed deformity

• Advanced knee joint damage due to inflammatory joint diseases

• Knee joint damage after trauma or previous fracture

• Knee pain and deformity that seriously limit daily life

Knee replacement may be considered in young, middle-aged or older patients for different reasons. Age alone does not determine the decision. What matters is the degree of joint damage, the patient’s symptoms, activity expectations, bone quality, ligament balance, general health condition and the expected benefit-risk balance of surgery.

Knee replacement is more meaningful when the main source of pain is the knee joint. Therefore, other causes that can create pain around the knee, such as hip arthritis, lumbar disc herniation, lumbar spinal stenosis, nerve compression, muscle-tendon problems or inflammatory diseases, should also be evaluated.

Knee replacement may become necessary due to different conditions. The common feature of these conditions is advanced damage to the knee joint surfaces, causing pain, limited motion, deformity or difficulty walking.

Main conditions that may require knee replacement include:

• Knee arthritis

• Inflammatory joint diseases

• Post-traumatic knee joint damage

• Previous fractures around the knee

• Severe varus deformity

• Severe valgus deformity

• Advanced cartilage loss in the knee joint

• Advanced joint damage after unsuccessful knee-preserving surgeries

• Certain congenital or structural knee deformities

• Advanced joint damage with ligament imbalance

In knee arthritis, the joint cartilage wears down over time, the joint space narrows, bone spurs may form and knee motion becomes increasingly restricted. Patients may experience pain, swelling, limited movement, difficulty with stairs and decreased walking distance.

In inflammatory joint diseases, the knee joint may become damaged due to the inflammatory process. In post-traumatic cases, previous fractures, joint surface irregularity, ligament injuries or alignment problems may lead to arthritis and pain over time.

In patients with severe bow-legged or knock-kneed deformity, load distribution may be disturbed. This may cause more wear on one side of the joint, pain and limited motion over time.

No. In mild or moderate knee arthritis, non-surgical methods such as weight control, exercise, activity modification, medication, physical therapy, cane use or injections may be sufficient. Knee replacement is usually considered when pain and functional loss become significant, joint damage reaches an advanced stage and non-surgical methods no longer provide sufficient relief.

The decision for knee replacement is made by evaluating the patient’s symptoms, physical examination findings, imaging results and response to non-surgical treatments together. A prosthesis decision should not be made simply because “arthritis is seen on X-ray.” Likewise, even if advanced joint damage is seen on X-rays, the decision should be individualized if the patient has only mild symptoms.

The most important questions in the decision-making process are:

• How much does the pain affect daily life?

• How far can the patient walk?

• How difficult are stairs, sitting and standing, or walking uphill and downhill?

• Is there knee pain at night or at rest?

• How restricted is knee range of motion?

• Is there a noticeable deformity or alignment problem in the knee?

• Is there a giving-way, insecurity or catching sensation in the knee?

• Has the patient benefited sufficiently from non-surgical treatments?

• Is the source of pain truly the knee joint?

• Is the patient’s general health suitable for surgery?

• Are the patient’s expectations realistic?

What Is Assessed During the Examination?

During knee examination, the location of pain, knee range of motion, whether the knee can fully straighten, how much the knee can bend, leg alignment, walking pattern, limping, ligament balance, muscle strength and associated hip-lower back problems are assessed.

The examination particularly evaluates:

• Knee flexion and extension

• Whether there is loss of full knee extension

• Swelling or increased fluid in the knee

• Tenderness in the inner and outer joint line

• Pain and movement around the kneecap

• Bow-legged or knock-kneed deformity

• Ligament stability

• Walking pattern and limping

• Muscle strength

• Signs of hip or lower back-related pain

• Signs of previous surgery or trauma

• The patient’s need for a cane or walker

Which Imaging Tests May Be Used?

The main imaging method in knee replacement evaluation is usually standing weight-bearing knee X-rays. These X-rays help evaluate joint space, cartilage loss, bone deformity, leg alignment and deterioration of joint surfaces.

In some patients, full-length leg alignment X-rays may be needed. These X-rays are used to evaluate the mechanical alignment between the hip, knee and ankle. Additional imaging such as computed tomography may be needed in patients with complex deformity, previous fracture, previous surgery or bone loss.

MRI is not necessary in every patient with advanced knee arthritis. MRI is more commonly used to evaluate early-stage cartilage, meniscus, ligament or bone marrow problems. In advanced arthritis cases planned for knee replacement, the decision is often made based on physical examination and appropriate weight-bearing X-rays.

The timing of knee replacement should not be a one-sided decision made only by looking at an X-ray. The patient’s pain, daily life expectations, activity goals, general health condition and ability to follow the postoperative rehabilitation process should be discussed together. The right patient, correct timing and realistic expectations improve the success of knee replacement.

During knee replacement surgery, the damaged knee joint surfaces are prepared and replaced with artificial joint components. The surgery may be performed under general anesthesia or regional anesthesia. The anesthesia method is determined according to the patient’s general health condition, additional diseases and anesthesia evaluation.

During surgery, the knee joint is accessed through an appropriate surgical approach. The damaged joint surfaces on the thigh bone and shin bone are prepared at specific angles. Metal components are placed on these bone surfaces, and a special polyethylene insert is placed between them. The joint surface of the kneecap is also evaluated.

The goal of knee replacement surgery is not only to replace damaged surfaces. The aims are to correct alignment, provide ligament balance, allow the knee to fully straighten and bend sufficiently, make the prosthesis stable and enable the patient to walk safely.

Which Structures Are Replaced During Surgery?

In total knee replacement, the damaged joint surfaces on the thigh bone and shin bone are usually replaced. Metal components are placed on these surfaces, and a special polyethylene insert is used between the two metal surfaces.

In some patients, the joint surface behind the kneecap may also be replaced with a prosthetic component. In other patients, the kneecap may be preserved. This decision depends on the condition of the kneecap joint surface, the patient’s anatomy, the source of pain and the surgeon’s assessment.

Is the Kneecap Always Replaced?

No. Whether the kneecap joint surface is replaced during knee replacement surgery varies from patient to patient. The condition of the kneecap cartilage, joint surface damage, kneecap tracking, pain source and the surgeon’s preferred method all affect this decision.

Whether the kneecap is replaced or preserved, the goal is to allow the knee to function in a painless, balanced and stable way. Therefore, the decision should not be based on a single rule, but on the patient’s knee structure.

Knee replacement is not performed with the exact same technical details in every patient. The surgical plan of a patient with straightforward primary knee arthritis may be different from that of a patient with severe deformity, ligament imbalance, previous fracture or previous surgery. Therefore, preoperative evaluation, X-ray planning and additional imaging when needed are important for proper implant placement.

Knee replacements may differ according to which part of the joint is replaced, how the implant is fixed to bone, ligament balance, deformity level and the anatomical needs of the patient. Implant selection is made according to the patient’s age, bone quality, location of knee damage, ligament status, range of motion, deformity and surgical goals.

Common knee replacement classifications include:

• Total knee replacement

• Partial knee replacement

• Unicompartmental knee replacement

• Patellofemoral replacement

• Cemented knee replacement

• Cementless knee replacement

• Posterior cruciate ligament-retaining designs

• Posterior cruciate ligament-substituting designs

• More constrained or hinged implant designs

• Revision knee replacements

Total knee replacement is the most commonly used type when there is advanced damage in more than one part of the knee joint. Partial knee replacement may be considered in selected patients when damage is limited to a specific part of the knee and ligament balance and patient selection are appropriate.

Total and Partial Knee Replacement

In total knee replacement, the main damaged surfaces of the knee joint are replaced. This method is commonly used when arthritis affects the inner and outer parts of the knee as well as the kneecap joint surface.

In partial knee replacement, only a specific part of the knee is replaced. This option is not suitable for every patient. Limited arthritis, adequate ligaments, overall knee alignment and range of motion are important in the decision-making process.

Cemented and Cementless Knee Replacement

In cemented knee replacement, the implant is fixed to the bone with a special material called bone cement. In cementless knee replacement, the implant surface is designed so that bone can grow into it over time. Both methods have patient groups in which they may be appropriate.

Cemented knee replacements have been widely used for many years. Cementless options may be preferred in some patients depending on bone quality, age, activity level and implant design. The decision is made according to the patient’s bone structure and surgical plan.

There is no single “best prosthesis” for everyone. The most appropriate prosthesis depends on the patient’s knee anatomy, bone quality, age, activity expectations, the cause of the disease, ligament balance and surgical goals. Success is determined not only by the implant brand, but also by correct patient selection, proper planning, appropriate surgical technique, rehabilitation and postoperative follow-up.

In patients planned for knee replacement surgery, the preparation process is important for a safer operation and a more controlled recovery period. This preparation includes not only the day of surgery, but also the first weeks after surgery and the rehabilitation process.

Before surgery, the patient’s general health condition, medications, blood thinners, diabetes control, heart-lung diseases, infection risk, dental and skin infections are evaluated. Additional consultations may be requested from relevant specialties when needed.

Maintaining muscle strength as much as possible before surgery, preserving knee range of motion within suitable limits, learning how to use walking aids, arranging the home environment and planning support after discharge may make the recovery process easier.

Which Checks Are Done Before Surgery?

In the preoperative evaluation, the patient’s general health condition is reviewed in detail. Blood tests, anesthesia evaluation, necessary heart and lung tests, medication adjustments and infection risk assessment are part of this process.

The following issues are particularly evaluated:

• Diabetes and blood sugar control

• Blood pressure and heart diseases

• Use of blood-thinning medications

• Kidney and liver function

• Presence of active infection

• Skin wound or infection risk around the knee

• Infection sources such as dental or urinary tract infection

• Bone quality

• Previous surgeries

• Anesthesia-related risks

• Rehabilitation compliance and home support

The purpose of these checks is not to delay surgery unnecessarily, but to reduce risk and prepare the patient for surgery more safely.

Why Is Home and Daily Life Preparation Important?

After knee replacement, it is important for the patient to walk safely, move without falling and meet daily needs in a controlled way during the first days. Therefore, preparing the home environment before surgery can be helpful.

Removing slippery rugs, placing frequently used items within easy reach, improving bathroom and toilet safety, providing an appropriate chair height and planning a walker or cane if needed may make the recovery process easier.

Support from a family member or caregiver should also be planned for the first days after discharge. Especially in older patients, home organization and safe movement training are important to reduce the risk of falls.

Yes. Blood sugar control, reducing infection sources, stopping smoking, maintaining muscle strength, improving home safety and informing the patient about the postoperative process may positively affect recovery. The better the preparation, the more controlled the postoperative period can be.

Recovery after knee replacement varies depending on the patient’s age, preoperative function, additional diseases, knee range of motion, surgical planning and rehabilitation compliance. In many patients, walking training begins in the early period after surgery. The goals are safe mobilization, pain control, reducing blood clot risk, preserving knee range of motion and planning return to daily life.

During the first days after surgery, pain control, wound care, use of walking aids, stair training, bending and straightening exercises and discharge planning are emphasized. The patient’s ability to move safely at home and understand the exercises is important in the discharge decision.

Although some patients feel relief in the early period, knee swelling, stiffness, limited motion and muscle weakness take time to recover. This process may vary from person to person.

Hospital Stay and First Walking

The length of hospital stay after knee replacement varies depending on the patient’s general condition, the features of the surgery and rehabilitation progress. Some patients may be discharged quickly, while patients with additional diseases or more complex surgery may require longer follow-up.

The first walking is usually done with the assistance of a physiotherapist or healthcare team. The patient is taught how to use a walker or cane, get out of bed, sit, use the toilet and climb stairs. The aim is for the patient to learn how to move safely.

Knee Range of Motion and Rehabilitation

Range of motion after knee replacement is an important factor affecting the outcome. Achieving full knee extension and sufficient bending is important for walking, stairs, sitting and standing and daily activities.

In rehabilitation, regular exercise, swelling control, muscle strengthening, gait training and safe activity progression are targeted. Overexertion or completely stopping exercises may negatively affect recovery. Therefore, rehabilitation should progress in a personalized and controlled way.

Although knee replacement is an effective surgical procedure, the patient’s active participation during recovery is important. Regular walking, recommended exercises, knee range of motion work, wound care, blood clot prevention measures, fall prevention and follow-up visits may affect long-term results.

Precautions after knee replacement may vary according to the surgical plan, implant type, patient’s age, muscle strength, balance status, knee range of motion and the surgeon’s rehabilitation protocol. The same exercise pace, movement target or activity duration does not apply to every patient.

General points to consider include:

• Avoiding falls

• Using walking aids correctly

• Keeping the wound clean and dry

• Monitoring for signs of infection

• Following medication and movement recommendations to reduce blood clot risk

• Performing knee range of motion exercises regularly

• Avoiding excessive and uncontrolled strain

• Paying attention to swelling control

• Avoiding heavy lifting

• Not missing follow-up visits

• Seeking medical care if sudden pain, marked swelling, wound drainage or shortness of breath occurs

How Should Swelling, Pain and Range of Motion Be Followed?

Some pain, swelling and limited motion may be expected in the early period after knee replacement. However, symptoms are expected to gradually decrease, walking should become safer and knee range of motion should improve over time.

Swelling control, regular exercise, resting the leg appropriately and correct use of recommended medications may help the recovery process. Progressively worsening pain, marked redness of the knee, rapidly worsening motion or wound drainage should not be considered normal.

Which Signs Are Important for Infection and Blood Clots?

Increasing redness around the wound, drainage, bad odor, fever, progressively worsening pain or deterioration in general condition after surgery may be warning signs of infection. If these findings occur, the patient should contact the physician without delay.

Marked leg swelling, calf pain, sudden shortness of breath, chest pain or unexplained palpitations should be evaluated carefully for blood clots. These symptoms may require urgent assessment.

Because knee replacement consists of metal and polyethylene artificial surfaces, some patients may feel mild sound, clicking or a mechanical sensation during movement. If there is no pain, swelling, giving-way sensation, catching or loss of motion, this does not always mean a serious problem. However, if sound is accompanied by pain or loss of function, evaluation is needed.

Knee replacement is an effective surgery that reduces pain and improves quality of life in many patients. However, like every surgical procedure, it has risks. These risks may vary according to the patient’s age, general health condition, bone quality, complexity of surgery, previous surgeries, knee deformity and additional diseases.

Possible risks of knee replacement surgery include:

• Infection

• Bleeding

• Blood clot formation

• Pulmonary embolism

• Knee stiffness and limited range of motion

• Loosening of the knee replacement

• Implant wear

• Periprosthetic fracture

• Ligament imbalance or instability

• Problems around the kneecap

• Nerve or vessel injury

• Wound healing problems

• Anesthesia-related risks

• Pain not completely resolving

• Need for revision surgery

The presence of these risks does not mean that every patient will develop a problem. However, the patient should clearly understand the possible risks, expected benefits, alternative treatment options and recovery process before surgery.

Early Risks

Early risks may occur during surgery or in the first days to weeks after surgery. Infection, wound problems, bleeding, blood clots, excessive knee stiffness, nerve involvement, wound healing problems or problems related to falls are important during this period.

Pain control, safe walking, blood clot prevention measures, wound care, knee range of motion exercises and fall prevention in the early period may help reduce risks. Sudden severe pain, fever, wound drainage, marked leg swelling or shortness of breath should be taken seriously.

Long-Term Risks

In the long term, implant wear, loosening, periprosthetic fracture, knee stiffness, instability, kneecap problems, late infection or the need for revision surgery may become relevant. Modern knee replacements generally have long implant survival; however, implant longevity may vary according to the patient’s age, activity level, bone quality, implant type and how the implant is used.

In young and active patients, the prosthesis may be expected to last for many years; however, the possibility of revision during the patient’s lifetime is not completely eliminated. Therefore, regular follow-up, evaluation of sudden pain and long-term monitoring of the prosthesis are important.

It is not possible to eliminate risks completely; however, careful patient selection, preoperative preparation, control of infection sources, appropriate surgical planning, correct implant positioning, ligament balancing, blood clot prevention strategies, safe mobilization, regular rehabilitation and long-term follow-up may help reduce risks. The patient’s adherence to recommendations is as important as surgical technique.

Is knee replacement only performed in very old patients?

False: Knee replacement is performed only in older patients.

Correct: Knee replacement is most commonly considered in older age groups, but it may also be necessary in young or middle-aged patients. Inflammatory joint diseases, post-traumatic joint damage, severe deformity or advanced arthritis developing at a younger age may make knee replacement necessary even in younger patients.

Does arthritis on X-ray always mean that knee replacement is necessary?

False: Every patient with knee arthritis on X-ray should have a knee replacement.

Correct: X-ray findings are important; however, the decision for surgery is not made based on imaging alone. The patient’s pain, walking capacity, stair function, knee range of motion, limitations in daily life, physical examination findings and response to non-surgical treatments should be evaluated together.

Does knee replacement make the knee completely natural again?

False: After knee replacement, the knee becomes completely like a natural knee.

Correct: Knee replacement aims to reduce pain and improve function by replacing damaged joint surfaces with artificial surfaces. Many patients experience significant relief in daily activities; however, a prosthesis is not a natural knee joint. Therefore, range of motion, muscle strength, exercise, implant longevity and regular follow-up are important.

Does knee replacement mean there will be no pain at all?

False: All pain completely disappears in every patient after knee replacement.

Correct: Knee replacement can be effective in reducing pain that comes from the knee joint. However, if some of the pain comes from the hip, lower back, nerve compression, muscle-tendon problems or another source, these symptoms may continue after surgery. Therefore, the source of pain should be identified correctly.

Is exercise harmful after knee replacement?

False: Exercise should be avoided after knee replacement so that the knee is not strained.

Correct: Controlled exercise and rehabilitation after knee replacement are important parts of recovery. Regular exercise is needed to preserve knee range of motion, improve muscle strength, correct walking and return to daily life. However, exercises should be performed within the limits recommended by the surgeon and physiotherapy team.

Does the best implant brand determine the result?

False: The success of surgery is determined only by the implant brand.

Correct: Implant quality is important; however, success is not determined by the brand alone. Correct patient selection, surgical planning, proper implant positioning, correction of leg alignment, ligament balance, infection prevention, rehabilitation and long-term follow-up are major factors in the final outcome.

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