This article provides a detailed overview of knee replacement surgery, covering everything from the reasons for the procedure to the different types of surgeries available.
You’ll also learn about the benefits, preoperative preparations, what to expect during and after the surgery, recovery time, and potential complications.
Whether you’re considering knee replacement surgery or just want to understand the process, this guide offers all the essential information you need.
What is a Knee Replacement Surgery?
Knee replacement surgery, also known as knee arthroplasty, is a medical procedure where damaged cartilage and bone in the knee joint are replaced with artificial implants.
The knee joint, composed of the femur (thigh bone), tibia (shin bone), and patella (kneecap), can suffer from wear and tear due to arthritis, injury, or other degenerative conditions.
During the surgery, the surfaces of the joint are smoothed, and a prosthetic joint made of metal, plastic, or ceramic is implanted to restore mobility and reduce pain.
Reasons for Knee Replacement Surgery
The most common reason for knee replacement surgery is osteoarthritis, which causes the cartilage in the knee joint to break down, leading to pain, stiffness, and reduced function. Other reasons include:
- Rheumatoid arthritis: An autoimmune disorder causing inflammation in the joint lining.
- Post-traumatic arthritis: Damage caused by a fracture or ligament injury that affects the knee.
- Severe pain: When pain from arthritis or injury limits daily activities such as walking, climbing stairs, or getting out of chairs.
- Deformity: A bowed or knocked-knee appearance due to joint degeneration.
In cases where non-surgical treatments like physical therapy, medications, or injections have failed to provide relief, knee replacement may be considered as a solution to improve quality of life.
Who is a Candidate for Knee Replacement?
Candidates for knee replacement are typically those who have experienced chronic knee pain and reduced mobility for an extended period. The ideal candidate generally fits into the following categories:
Patients with severe osteoarthritis or rheumatoid arthritis
Their knee joints have deteriorated to the point where they experience significant pain and restricted mobility.
Adults over the age of 50:
Knee replacement is more common among older individuals whose joints have experienced long-term wear and tear.
Younger patients with traumatic injuries:
Athletes or individuals with joint damage from accidents may also require knee replacements.
What are the Benefits of Knee Replacement Surgery?
Knee replacement surgery provides several important benefits to those suffering from knee joint issues:
Pain relief: The primary reason for surgery is to alleviate chronic pain caused by damaged knee cartilage and bone.
Improved mobility: After recovery, patients typically experience significant improvement in their ability to walk, climb stairs, and engage in low-impact activities.
Better quality of life: Pain-free movement allows patients to regain their independence and return to daily activities.
Correction of deformity: If the patient’s knee has become misshapen due to arthritis or injury, surgery can restore its natural alignment.
Types of Knee Replacement Surgery
Knee replacement surgery comes in several forms, each tailored to the extent of the joint damage:
Total knee replacement (TKR):
This is the most common type, where the entire knee joint is replaced with artificial components.
Partial knee replacement (PKR):
Only the damaged part of the knee is replaced, leaving the healthy parts of the joint intact.
Bilateral knee replacement:
Both knees are replaced at the same time or in stages.
Revision knee replacement:
For patients who’ve previously had a knee replacement but need a second surgery due to wear, loosening, or infection.
Types and Devices Used in Knee Replacement
Various materials and devices are used during knee replacement surgery, chosen based on the patient’s age, weight, activity level, and specific joint condition:
- Fixed-bearing implants: These have a static component attached to the tibia, providing long-term stability.
- Mobile-bearing implants: These implants allow greater flexibility, designed for younger, more active patients.
- Posterior-stabilized designs: These use an internal cam and post to mimic the knee’s natural motion.
- Cruciate-retaining designs: Used when the patient’s ligaments are intact, retaining more of the knee’s original structure.
Read more about: knee replacement devices
Preoperative Preparation for Knee Replacement
Prior to surgery, patients need to undergo various preparations, including:
Medical evaluation:
A complete physical examination and assessment by the surgical team to ensure the patient is in good health for surgery.
Blood tests and imaging:
X-rays or MRI scans to understand the condition of the knee joint.
Physical therapy consultation:
Patients may be advised to begin exercises that strengthen the muscles around the knee to aid in recovery post-surgery.
Medication review:
Patients may need to stop taking certain medications that could interfere with surgery, such as blood thinners.
Read mor about: Preparing for Knee Replacement Surgery
What Happens During a Knee Replacement?
During the procedure, the patient is usually placed under general or spinal anesthesia. The surgery typically follows these steps:
Incision: A 6- to 10-inch incision is made along the front of the knee.
Removal of damaged tissue: The surgeon removes damaged bone and cartilage from the femur, tibia, and kneecap.
Implant insertion: The prosthetic components are fitted to the bone, mimicking the joint’s natural anatomy.
Closure: The incision is closed with stitches or staples, and a bandage is applied.
How Long Does a Knee Replacement Take?
The surgery typically takes about 1 to 2 hours, depending on the complexity of the procedure and whether it’s a partial or total replacement.
What Does a Knee Replacement Look Like?
A knee replacement consists of three main parts:
- Femoral component (metal): Replaces the end of the thigh bone.
- Tibial component (metal and plastic): Covers the top of the shin bone.
- Patellar component (plastic): Substitutes the kneecap’s surface.
The prosthetic knee allows the joint to bend smoothly and support the body’s weight, much like a natural knee.
Read about: Custom Knee Implants
What Happens After a Knee Replacement?
After surgery, the patient is taken to recovery, where vital signs are monitored. Once stabilized:
- Pain management: Painkillers are administered to manage discomfort.
- Physical therapy: Therapy starts within 24 hours to regain mobility and flexibility in the joint.
- Hospital stay: Most patients stay in the hospital for 2-3 days, depending on their progress.
How Long Does it Take to Recover from a Knee Replacement?
Recovery typically takes 6 to 12 weeks, but it can vary based on individual health and surgery complexity. During this time:
Physical therapy:
Regular sessions help restore strength and mobility.
Walking aids:
Patients use crutches or walkers for several weeks after surgery.
Return to normal activities:
Most patients can return to their normal daily activities within 3 months, but it may take 6 months or more for full recovery.
How Long Does a Knee Replacement Last?
Knee replacements typically last 15 to 20 years. However, advancements in implant technology have improved their longevity, and some newer implants can last even longer, particularly in less active patients.
Read about: Knee Replacement for Athletes
Exercises After Knee Replacement
Post-surgery exercises play a crucial role in the recovery process. Key exercises include:
- Quadriceps sets: Strengthen the thigh muscles.
- Heel slides: Improve range of motion by sliding the foot towards the body.
- Straight leg raises: Help strengthen the muscles around the knee joint.
- Stationary cycling: Once cleared by the doctor, low-impact cycling can improve flexibility and stamina.
Read more about: Pain Management After Knee Replacement
Read more about: best exercises after knee replacement
Best Diet After Knee Replacement
A balanced diet promotes faster recovery and bone healing. Some recommendations include:
Protein-rich foods:
Lean meats, fish, eggs, and legumes to support tissue repair.
Calcium and Vitamin D:
Dairy products, leafy greens, and fortified foods to strengthen bones.
Omega-3 fatty acids:
Found in fish, nuts, and seeds, which help reduce inflammation.
Hydration:
Drinking plenty of water aids in healing and prevents complications like blood clots.
Read our full Best Diet After Knee Replacement guide
What are Potential Complications of a Knee Replacement?
While knee replacement surgery is generally safe, there are potential risks:
Infection: Can occur at the incision site or deeper within the joint.
Blood clots: May form in the legs, requiring blood-thinning medication to reduce the risk.
Implant loosening or failure: In rare cases, the implant may wear out or fail, requiring revision surgery.
Nerve or blood vessel damage: The surgery can sometimes damage nerves or blood vessels in the area.
Rread more about: Common Complications After Knee Replacement
Alternatives to Knee Replacement Surgery
If knee replacement isn’t suitable or desired, alternatives may include:
Medications:
Nonsteroidal anti-inflammatory drugs (NSAIDs) and corticosteroids to manage pain and inflammation.
1- Physical therapy:
Targeted exercises to strengthen the muscles around the knee.
2- Knee injections:
Hyaluronic acid or corticosteroid injections to provide temporary relief.
3Arthroscopy:
A minimally invasive procedure to clean up damaged cartilage.
Read our full Alternatives to Knee Replacement Surgery guide
Cost of Knee Replacement
The cost of knee replacement surgery can vary significantly based on factors like location, whether the procedure is performed on an inpatient or outpatient basis, and whether you have insurance coverage.
Read our full guide: Cost of Knee Replacement
Conclusion
Knee replacement surgery offers a new lease on life for individuals burdened by joint pain and limited mobility, providing significant improvements in daily activities and overall well-being.
Understanding the procedure, from the preoperative preparation to the postoperative recovery, is essential for patients to make informed decisions about their health.
With proper care, including post-surgical exercises and a balanced diet, most knee replacements can last for decades, allowing individuals to enjoy pain-free movement.
Although complications are possible, the benefits of knee replacement often far outweigh the risks, offering a long-term solution for those suffering from chronic knee problems.
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FAQs
how painful is a total knee replacement?
Pain after a total knee replacement is common, especially in the first few weeks, but it can be managed with pain medication and physical therapy.
what is the most commonly reported problem after knee
Stiffness and difficulty in regaining full range of motion are the most commonly reported issues after knee replacement.
Is a knee replacement a major operation?
Yes, knee replacement is considered a major surgery that involves replacing damaged parts of the knee joint with artificial implants.
Is knee replacement surgery risks?
Like any surgery, knee replacement has risks, including infection, blood clots, and implant failure, but these risks are relatively low with modern techniques.
What is the best knee replacement procedure?
The best procedure depends on the patient’s condition. Total knee replacement is the most common, but partial knee replacement may be better for those with localized damage.
How long does it take to walk normally after knee replacement?
Most patients can walk with support within a few days, but it typically takes 6 to 12 weeks to walk normally without assistance.
Who Cannot have knee replacement surgery?
Patients with severe infections, certain heart conditions, or poor overall health may not be suitable candidates for knee replacement surgery.