By Dr Ho Way Siong (Nicholas), Consultant Orthopaedic & Trauma Surgeon
Key Takeaways
- Knee replacement surgery is typically recommended when severe knee arthritis causes persistent pain, stiffness or reduced mobility that no longer improves with conservative treatments.
- The decision to have surgery is based on your symptoms, physical function, imaging findings and overall health, not age alone.
- Several treatment options are available, including total knee replacement, partial knee replacement and robotic-assisted surgery, depending on your individual condition.
- Successful outcomes depend on both the surgery and your commitment to physiotherapy, rehabilitation and long-term joint care.
Knee replacement surgery is performed when severe joint damage causes persistent pain, stiffness and difficulty with everyday activities, often due to conditions such as osteoarthritis.
During the procedure, damaged surfaces of the knee joint are removed and replaced with artificial components, usually covering the ends of the thighbone (femur) and shinbone (tibia), with a plastic spacer placed between them. In some cases, the underside of the kneecap (patella) may also be resurfaced.
The artificial joint is designed to recreate the knee’s natural movement, allowing the components to glide smoothly against each other and helping restore mobility and reduce pain.
7 Signs You May Need Knee Replacement Surgery
Not every person with knee arthritis requires surgery.
However, if your symptoms continue to worsen despite appropriate treatment, it may be time to speak with an orthopaedic surgeon.
Below are seven common signs that knee replacement surgery may be worth discussing.
1. Your Knee Pain Persists Despite Conservative Treatment
Persistent pain is often the biggest reason patients consider surgery.
You may have already tried:
- Physiotherapy
- Pain-relieving medications
- Anti-inflammatory medication
- Weight loss
- Walking aids
- Knee braces
- Corticosteroid injections
- Hyaluronic acid injections
- Activity modification
If these treatments no longer provide meaningful relief, surgery may offer a more durable solution.
2. Knee Pain Is Affecting Your Sleep
Pain that regularly wakes you during the night is often a sign of advanced joint disease.
Many patients report:
- Difficulty finding a comfortable sleeping position
- Night-time throbbing pain
- Pain while resting
- Needing pain medication simply to sleep
When pain occurs even without activity, it suggests that arthritis has progressed beyond simple “wear and tear.”
3. Walking Has Become Increasingly Difficult
One of the earliest functional changes is reduced walking ability.
You may notice that you:
- Walk more slowly
- Avoid longer distances
- Need frequent rest stops
- Use a walking stick
- Avoid shopping centres
- Skip family outings
- Find travelling difficult
These changes often develop gradually, making them easy to overlook until mobility becomes significantly limited.
4. Climbing Stairs Has Become a Daily Challenge
The knee experiences several times your body weight when climbing stairs.
As cartilage deteriorates, this movement often becomes one of the most painful daily activities.
You may notice:
- Holding onto handrails
- Climbing one step at a time
- Leading with the stronger leg
- Avoiding staircases whenever possible
Difficulty using stairs can significantly affect independence, especially in multi-storey homes.
5. Your Knee Has Become Stiff and Difficult to Move
Advanced arthritis doesn’t only cause pain, it also reduces flexibility.
You may struggle to:
- Fully straighten your knee
- Bend it comfortably
- Sit on low chairs
- Get into a car
- Squat
- Kneel
- Stand up after sitting
Morning stiffness or stiffness after periods of inactivity may gradually last longer as arthritis progresses.
6. Your Knee Is Becoming Bowed or Knock-Kneed
As cartilage wears away unevenly, the alignment of the knee may gradually change.
You or your family may notice that:
- Your legs appear bowed
- Your knees angle inward
- Your walking pattern changes
- Shoes wear unevenly
- The knee feels unstable
These changes place additional stress on the joint and may accelerate further damage.
7. Knee Pain Is Limiting Your Quality of Life
Perhaps the most important sign isn’t what your X-ray shows, it’s how your knee affects your daily life.
When knee pain begins to interfere with the activities that matter most to you, it’s worth discussing your options with an orthopaedic specialist.
What Causes Knee Damage That Leads to Replacement Surgery?
Knee replacement surgery isn’t a treatment for just one condition. Rather, it is a solution for advanced joint damage that causes persistent pain, stiffness and loss of function when other treatments are no longer effective.
Understanding the underlying cause helps your orthopaedic surgeon recommend the most appropriate treatment and determine whether surgery is the right option.
1. Osteoarthritis: The Most Common Cause of Knee Replacement
Osteoarthritis is responsible for the majority of knee replacement surgeries worldwide.
Often referred to as “wear-and-tear arthritis,” osteoarthritis develops when the smooth cartilage covering the ends of the bones gradually wears away.
Without this protective layer:
- Bones rub against each other.
- The joint becomes inflamed.
- Bone spurs (osteophytes) may develop.
- The knee becomes stiff and painful.
- Everyday movements become increasingly difficult.
Although aging increases the risk, osteoarthritis is not simply an inevitable part of getting older. Factors such as obesity, previous injuries, genetics and repetitive stress can accelerate cartilage degeneration.
2. Rheumatoid Arthritis
Unlike osteoarthritis, rheumatoid arthritis (RA) is an autoimmune disease.
Instead of wearing away naturally, the body’s immune system mistakenly attacks the lining of the joints (synovium), causing chronic inflammation.
Over time, this inflammation can:
- Destroy cartilage
- Damage bone
- Weaken ligaments
- Cause joint deformity
- Lead to permanent disability if untreated
Although modern medications have significantly improved RA management, some patients still develop severe joint damage requiring knee replacement surgery.
3. Post-Traumatic Arthritis
A serious knee injury can increase the risk of arthritis years, even decades, later.
This is known as post-traumatic arthritis.
The damage may result from:
- Knee fractures
- Torn ligaments (such as the ACL or PCL)
- Meniscus injuries
- Cartilage injuries
- Previous knee dislocations
Even after successful treatment, the injured joint may not function exactly as before, leading to uneven wear and gradual cartilage loss.
Patients are often surprised when arthritis develops long after the original injury has healed.
4. Previous Knee Injuries
Not every previous injury immediately causes arthritis, but repeated trauma can gradually damage the joint.
Examples include:
- Sports injuries
- Repetitive occupational strain
- Untreated ligament instability
- Chronic meniscus tears
- Recurrent kneecap dislocations
These conditions may alter the way weight is distributed across the knee, increasing stress on the cartilage over time.
5. Avascular Necrosis (Osteonecrosis)
Avascular necrosis occurs when the blood supply to part of the bone is disrupted.
Without adequate blood flow, the affected bone gradually weakens and collapses, damaging the joint surface.
Although less common, it can lead to severe arthritis requiring knee replacement.
Risk factors include:
- Long-term corticosteroid use
- Excessive alcohol consumption
- Certain medical conditions
- Previous trauma
6. Knee Deformities
Some people develop abnormal knee alignment due to:
- Bow legs (varus deformity)
- Knock knees (valgus deformity)
- Congenital conditions
- Previous fractures
Abnormal alignment causes uneven loading across the joint.
Over many years, this uneven pressure accelerates cartilage wear and increases the likelihood of severe arthritis.
7. Other Less Common Causes
Less frequently, knee replacement may also be recommended for:
- Certain inflammatory joint diseases
- Severe joint infections that have damaged cartilage
- Tumours affecting the knee joint
- Haemophilia-related joint damage
- Advanced cartilage disorders
These conditions are less common but may still cause significant pain and disability.
How Do Orthopaedic Surgeons Decide If You Need Knee Replacement?
Many people assume surgery is recommended simply because an X-ray looks severe.
In reality, the decision is based on the whole patient, not just the knee.
Step 1: Understanding Your Medical History
Your consultation usually begins with a detailed discussion about your symptoms.
Your surgeon may ask:
- When did the pain begin?
- Where is the pain located?
- Is the pain constant or intermittent?
- Does it wake you at night?
- What activities make it worse?
- Have you tried physiotherapy?
- Have injections helped?
- What medications do you take?
- How does the pain affect your daily life?
Understanding how your symptoms have progressed often provides valuable clues about the severity of your condition.
Step 2: Physical Examination
Your orthopaedic surgeon will examine your knee to assess:
- Alignment
- Swelling
- Tenderness
- Range of motion
- Stability
- Muscle strength
- Walking pattern (gait)
- Ability to climb onto the examination couch
- Balance
These findings help determine whether surgery is likely to improve both pain and function.
Step 3: X-rays
Weight-bearing X-rays remain the primary imaging test for knee arthritis.
They allow surgeons to assess:
- Joint space narrowing
- Bone spurs
- Bone alignment
- Bone deformity
- Cartilage loss (indirectly)
- Severity of arthritis
X-rays also help determine whether a partial or total knee replacement may be appropriate.
Step 4: Is an MRI Always Necessary?
Not usually.
Unlike ligament injuries or sports-related knee problems, MRI scans are not routinely required before knee replacement surgery.
If X-rays clearly show advanced arthritis, additional MRI imaging often provides little extra information.
However, your surgeon may request an MRI if:
- The diagnosis is uncertain.
- Your symptoms don’t match the X-ray findings.
- Other conditions are suspected.
- You’re younger and joint-preserving treatments are being considered.
Step 5: Blood Tests
Blood tests help ensure that surgery can be performed safely.
They may be used to:
- Check for anaemia
- Assess kidney function
- Evaluate blood sugar levels
- Identify signs of infection
- Investigate inflammatory arthritis
- Assess overall fitness for surgery
If you have existing medical conditions such as diabetes or heart disease, additional tests may also be required.
Step 6: Assessing the Severity of Arthritis
Rather than relying on pain alone, surgeons evaluate how much arthritis affects your daily life.
They consider:
- Walking distance
- Ability to climb stairs
- Knee stiffness
- Night pain
- Use of walking aids
- Independence
- Participation in work or hobbies
- Response to previous treatments
The goal is to understand how much your knee limits your quality of life, not just what the X-ray shows.
6 Knee Replacement Options: Which One Is Right for You?
Not all knee replacements are the same.
The best procedure depends on:
- Which part of your knee is damaged
- The severity of arthritis
- Ligament stability
- Bone quality
- Your age
- Activity level
- Overall health
- Your expectations after surgery
Your orthopaedic surgeon will recommend the option most likely to provide long-term pain relief and improved function.
1. Total Knee Replacement (TKR)
A total knee replacement replaces the damaged surfaces of the femur, tibia and, in selected patients, the underside of the kneecap.
It is the most commonly performed knee replacement procedure.
Best suited for:
- Advanced osteoarthritis affecting multiple parts of the knee
- Severe rheumatoid arthritis
- Significant deformity
- Bone-on-bone arthritis
Advantages
- Reliable pain relief
- Improved mobility
- Long-term durability
- Suitable for widespread joint damage
Considerations
- Larger operation than partial replacement
- Longer rehabilitation than some smaller procedures
- Requires commitment to physiotherapy
2. Partial Knee Replacement (Unicompartmental Knee Replacement)
Not all arthritis affects the entire knee.
If damage is limited to a single compartment, a partial knee replacement may be an option.
Only the damaged portion of the joint is replaced, preserving more of your natural bone and ligaments.
Suitable for patients with:
- Arthritis confined to one compartment
- Intact knee ligaments an intact anterior cruciate ligament (ACL) is mandatory for standard fixed-bearing partial knee replacements to maintain proper joint kinematics and prevent early construct failure
- Good range of motion
- Minimal deformity
Advantages
- Smaller incision
- Less bone removal
- Faster recovery for many patients
- More natural knee movement
Limitations
Not everyone qualifies. If arthritis is widespread, a total knee replacement usually provides better long-term results.
3. Bilateral Knee Replacement
Some patients have severe arthritis in both knees.
A bilateral knee replacement may be performed:
- Simultaneously (both knees during one operation), or
- Staged (each knee operated on separately).
Potential Benefits
- One hospital admission
- One rehabilitation period
- Overall shorter treatment journey
Considerations
Simultaneous bilateral surgery is not suitable for everyone. Your surgeon will assess your age, general health and fitness before recommending this approach.
4. Robotic-Assisted Knee Replacement
Robotic-assisted technology is increasingly used to help surgeons plan and perform knee replacement with a high degree of precision.
Contrary to popular belief, the robot does not perform the surgery independently. Your orthopaedic surgeon remains in control throughout the procedure, using the robotic system as an advanced tool to assist with implant positioning and bone preparation.
Potential advantages may include:
- Greater surgical precision
- Improved implant alignment
- Better preservation of healthy bone
- More personalised implant positioning
Whether robotic-assisted surgery is appropriate depends on your condition, anatomy and the facilities available.
5. Traditional Knee Replacement
Traditional knee replacement techniques have been successfully performed for decades and continue to provide excellent outcomes for many patients.
Experienced surgeons use specialised instruments and careful planning to position implants accurately and restore knee function.
Both traditional and robotic-assisted approaches can achieve excellent results when used in the right patient.
6. Cemented vs Cementless Implants
Your surgeon will also decide how the implant should be fixed to your bone.
Cemented Implants
A specialised bone cement secures the implant in place.
Advantages:
- Immediate fixation
- Long track record
- Suitable for many older adults and patients with reduced bone quality
Cementless Implants
These implants are designed to allow bone to grow into their surface over time.
Advantages:
- Biological fixation
- Often considered for younger patients with good bone quality
The choice depends on your bone health, age, activity level and the surgeon’s assessment.
How Should You Prepare for Knee Replacement Surgery?
Preparation begins several weeks before your operation.
Your orthopaedic team will work with you to ensure you’re medically fit for surgery and understand what to expect during recovery.
Good preparation can help reduce complications and improve your rehabilitation.
1. Pre-Operative Assessment
Before surgery, you’ll attend a pre-admission or pre-operative assessment.
This appointment allows your healthcare team to evaluate your overall health and identify any conditions that should be optimised beforehand.
The assessment may include:
- Review of your medical history
- Physical examination
- Blood tests
- Electrocardiogram (ECG), if required
- Chest X-ray (for selected patients)
- Medication review
- Anaesthetic assessment
If you have chronic conditions such as diabetes, high blood pressure or heart disease, these should be well controlled before surgery.
2. Discuss Your Medications
Tell your doctor about all medicines and supplements you take, including:
- Prescription medications
- Over-the-counter painkillers
- Herbal supplements
- Vitamins
- Blood-thinning medications
Some medicines, particularly anticoagulants (blood thinners), may need to be adjusted or temporarily stopped before surgery.
Do not stop any medication without consulting your healthcare provider.
3. Strengthen Your Knee Before Surgery (Prehabilitation)
One of the biggest advances in joint replacement care is prehabilitation, strengthening your body before surgery.
Research shows that improving muscle strength beforehand can help support recovery afterwards.
Your physiotherapist may recommend exercises to improve:
- Quadriceps strength
- Hamstring strength
- Hip muscles
- Balance
- Flexibility
- Walking endurance
Even modest improvements before surgery may make rehabilitation easier afterwards.
4. Optimise Your Overall Health
Small lifestyle changes before surgery can have a meaningful impact on recovery.
Your doctor may advise you to:
- Maintain a healthy weight
- Stop smoking
- Eat a balanced, protein-rich diet
- Control blood sugar if you have diabetes
- Stay physically active within your comfort level
These measures can help reduce the risk of infection and support wound healing.
5. Prepare Your Home
Recovery is often easier when your home is ready before you return.
Consider:
- Removing loose rugs and trip hazards
- Installing handrails if needed
- Placing frequently used items within easy reach
- Arranging a comfortable chair with supportive armrests
- Preparing meals in advance
- Asking family or friends to help during the first few weeks
Planning ahead allows you to focus on recovery once you’re home.
What Happens During Knee Replacement Surgery?
Although the exact technique varies depending on the procedure, most operations follow similar steps.
Your surgeon will:
- Make an incision over the knee.
- Remove the damaged cartilage and a small amount of underlying bone.
- Prepare the bone surfaces.
- Position the artificial components.
- Check the knee’s stability, movement and alignment.
- Close the incision with sutures or staples.
- Apply a dressing.
The operation usually takes between one and two hours, although complex cases may take longer.
What Risks and Complications Should You Know About?
Knee replacement surgery is one of the most successful orthopaedic procedures performed today, helping many people achieve significant pain relief and improved mobility. Like any major operation, however, it carries potential risks and complications.
1. Infection
Although uncommon, infection is one of the most serious complications of knee replacement surgery.
An infection may occur:
- Around the surgical wound
- Deep around the artificial joint
- Weeks, months or even years after surgery (rare)
Symptoms may include:
- Increasing redness around the incision
- Swelling that worsens rather than improves
- Persistent wound drainage
- Fever or chills
- Severe pain that suddenly increases after initial improvement
Depending on its severity, treatment may involve antibiotics, surgical cleaning of the joint or, in rare cases, revision surgery.
2. Blood Clots (Deep Vein Thrombosis)
Reduced mobility after surgery can increase the risk of developing blood clots in the legs.
To minimise this risk, your healthcare team may recommend:
- Early mobilisation
- Blood-thinning medication
- Compression stockings
- Leg exercises
- Adequate hydration
- Intermittent Pneumatic Compression (IPC) devices during the inpatient phase and early ambulation. It’s also worth noting that aspirin is increasingly used as first-line thromboprophylaxis alongside formal anticoagulants for low-risk patients.
Seek immediate medical attention if you develop:
- Sudden calf pain
- Significant swelling in one leg
- Chest pain
- Shortness of breath
These symptoms may indicate a medical emergency.
3. Persistent Stiffness
Some patients experience reduced knee movement after surgery.
Risk factors include:
- Severe stiffness before surgery
- Delayed physiotherapy
- Excessive scar tissue formation
- Poor adherence to rehabilitation exercises
Most stiffness improves with dedicated physiotherapy, although additional treatment is occasionally required.
4. Implant Loosening or Wear
Modern knee implants are designed to last for many years.
However, over time:
- The implant may gradually loosen.
- The plastic bearing surface may wear.
- Bone around the implant may change.
These changes may eventually require revision knee replacement surgery, although advances in implant materials have improved long-term durability.
5. Nerve or Blood Vessel Injury
Because important nerves and blood vessels lie close to the knee joint, there is a small risk of injury during surgery.
Fortunately, this complication is uncommon.
6. Persistent Pain
Most patients experience substantial pain relief after surgery.
However, a small proportion continue to have discomfort due to:
- Scar tissue
- Soft tissue irritation
- Spine or hip problems
- Implant-related issues
- Other underlying medical conditions
If pain persists, your orthopaedic surgeon will investigate the cause and recommend appropriate treatment.
7. Revision Surgery
Although knee replacements are designed to be durable, they do not last forever.
Revision surgery may be necessary because of:
- Implant wear
- Infection
- Implant loosening
- Fracture around the implant
- Persistent instability
Revision surgery is generally more complex than the initial operation but can restore function in appropriately selected patients.
How Can You Reduce Your Risk of Complications?
While no surgery is completely risk-free, you can play an important role in supporting a safe recovery.
Before surgery:
- Stop smoking if possible.
- Manage chronic medical conditions such as diabetes or high blood pressure.
- Maintain a healthy weight.
- Follow your surgeon’s pre-operative instructions.
After surgery:
- Attend all follow-up appointments.
- Perform your physiotherapy exercises consistently.
- Take prescribed medications as directed.
- Keep your wound clean and dry.
- Contact your healthcare team if you notice concerning symptoms.
Life After Knee Replacement Surgery
How Is Pain Managed?
Many patients worry that recovery will be extremely painful.
While some discomfort is expected, modern pain management aims to keep you comfortable enough to begin rehabilitation early.
Pain control may include:
- Oral pain medication
- Intravenous pain relief
- Local anaesthetic techniques
- Ice therapy
- Elevation of the leg
- Multimodal analgesia and peripheral nerve blocks (such as adductor canal blocks or periarticular local infiltration analgesia). Mentioning nerve blocks provides major reassurance to patients terrified of post-op pain.
Your healthcare team will regularly assess your pain and adjust treatment if necessary.
Will I Be Able to Walk Straight Away?
One of the biggest surprises for many patients is how soon they begin moving after surgery.
In many cases, a physiotherapist will help you sit out of bed, stand safely, and take your first steps using a walking frame or crutches.
Early mobilisation helps:
- Improve circulation
- Reduce the risk of blood clots
- Prevent muscle weakness
- Build confidence
- Support faster recovery
Can I Kneel After Knee Replacement?
Many people can kneel after surgery, but it may feel uncomfortable due to numbness or pressure around the incision. If kneeling is important for work, hobbies or religious practices, your surgeon or physiotherapist can advise you on safe techniques.
Are There Any Activities I Should Avoid?
To help protect your implant and maximise its lifespan, high-impact activities such as long-distance running, jumping sports and contact sports are generally discouraged.
How Does Physiotherapy Help You Recover After Knee Replacement?
The operation is only one part of your recovery.
Physiotherapy plays a vital role in helping you regain strength, mobility and confidence. These may include:
Ankle Pumps
Gentle up-and-down movements of your ankles to improve blood circulation and reduce the risk of blood clots.
Knee Bending Exercises
Gradually increasing your knee’s range of motion helps prevent stiffness and improves flexibility.
Straight Leg Raises
These exercises strengthen the quadriceps, which play an important role in walking and climbing stairs.
Walking Practice
You’ll learn how to:
- Use a walking frame or crutches correctly
- Turn safely
- Sit down and stand up
- Walk short distances confidently
Knee Replacement Myths vs Facts
| Myth | Fact |
| You should wait until you’re very old before having knee replacement surgery. | Surgery is recommended based on symptoms, joint damage and quality of life, not age alone. |
| A knee replacement will feel exactly like a natural knee. | Most patients experience excellent pain relief and improved function, but the knee may feel different from a natural joint. |
| You’ll never be able to kneel again. | Many patients can kneel after recovery, although it may feel uncomfortable for some. |
| Knee replacements only last 10 years. | Many modern implants last 15–20 years or longer, depending on individual factors. |
| Exercise will wear out the implant quickly. | Low-impact exercise is encouraged and supports long-term joint health. |
| Recovery ends after six weeks. | Recovery continues for several months, with many patients noticing improvements for up to a year after surgery. |
Take a Proactive Step Towards Better Joint Health
At Hospital Seri Botani, we understand that deciding to undergo knee replacement surgery is a significant step. Our goal is to provide personalised care at every stage of your journey, from your first consultation through rehabilitation and long-term follow-up.
Our multidisciplinary team works closely together to ensure that every patient receives a treatment plan tailored to their condition, lifestyle and recovery goals.
Our services include:
- Comprehensive orthopaedic assessment and diagnosis
- Individualised treatment planning
- Conservative management for early-stage knee conditions
- Knee replacement surgery for suitable candidates
- Personalised physiotherapy and rehabilitation programmes
- Ongoing follow-up to support long-term recovery
Our orthopaedic specialists are committed to helping you make informed decisions through personalised assessments, evidence-based treatment and comprehensive rehabilitation, so you can take confident steps towards moving more comfortably again.
Chronic knee pain can sometimes be linked to underlying health conditions such as obesity, diabetes or other medical issues that may influence treatment and recovery. Understanding your overall health can help your healthcare team recommend the most appropriate care.
Explore our Health Screening Packages to gain a clearer picture of your health and take a proactive step towards maintaining strong joints and overall wellbeing.
FAQs
- How much does knee replacement surgery cost in Malaysia?
The cost varies depending on factors such as the hospital, implant type, surgeon’s fees, room category and whether additional treatments are required. During your consultation, your healthcare team can provide a personalised cost estimate based on your treatment plan.
- Is knee replacement surgery covered by insurance?
Many medical insurance plans cover knee replacement surgery when it is considered medically necessary. Coverage differs between policies, so it’s advisable to check with your insurer and speak with the hospital’s admissions team regarding pre-authorisation requirements.
- Can EPF be used to pay for knee replacement surgery?
Depending on your eligibility and the prevailing Employees Provident Fund (EPF) withdrawal schemes, you may be able to use EPF savings for certain medical treatments. Check directly with EPF or ask the hospital for guidance on the application process.
- What should I prepare before hospital admission?
Your surgeon will provide specific instructions, but preparation commonly includes reviewing your medications, arranging transport home, preparing your living environment for recovery and packing essential personal items for your hospital stay.
- How many days should I take leave from work?
The amount of leave depends on your recovery and the physical demands of your job. Office workers may return within several weeks, while physically demanding occupations often require a longer recovery period. Your surgeon will provide advice based on your progress.
- How long is the waiting time for surgery?
Waiting times vary depending on your medical condition, required investigations, surgeon availability and hospital scheduling. If surgery is recommended, your healthcare team will discuss the expected timeline with you.
- Can I have both knees replaced at the same time?
Some patients are suitable candidates for simultaneous bilateral knee replacement, while others benefit from staged procedures. The decision depends on your overall health, the severity of arthritis in both knees and your surgeon’s assessment.
- How long does this implant last?
Many modern knee replacement implants continue to function well for 15 to 20 years or longer. Longevity depends on individual factors such as age, activity level, body weight and adherence to follow-up care.
Modern registry data (e.g., Australian and UK National Joint Registries) demonstrates that over 80–85% of total knee replacements last up to 25 years.
