What is Knee Joint Replacement
Knee joint replacement, also termed knee arthroplasty, is a surgical intervention to replace damaged or degenerated knee joint components with prosthetic parts. This procedure primarily addresses the wear and tear of the knee joint due to conditions like osteoarthritis or injury.
The knee joint itself comprises the surfaces of the thigh bone (femur) connecting with the shin bone (tibia), cushioned by the disc-shaped meniscal cartilages:
- The medial area on the inner side connects the femur and tibia bones.
- The lateral area is found on the outer side, linking the femur and tibia bones.
- The underside of the kneecap or patella.
This surgical procedure offers two primary approaches:
- Total Knee Replacement (TKR): Involves capping all three joint surfaces with specially crafted metal and plastic components, providing comprehensive restoration.
- Partial Knee Replacement: Targets specific joint areas, replacing only the affected or damaged portions with prosthetic components, preserving healthy segments of the knee joint.
The decision between total and partial knee replacement often depends on the extent of damage, patient-specific factors, and the recommendations provided by orthopedic specialists.
Who Would Need Knee Replacement Surgery
Knee replacement surgery is a solution for alleviating severe arthritic symptoms that significantly impact daily life. These symptoms include:
- Chronic arthritic pain, swelling, and stiffness that disrupt essential functions like sleep, walking, and self-care activities such as bathing.
- Cases where conventional, non-surgical treatments fail to provide substantial relief.
The knee can be affected by various forms of arthritis, each impacting the joint in distinct ways:
- Osteoarthritis: Gradual breakdown of the meniscal cartilage, leading to pain and reduced mobility.
- Rheumatoid Arthritis: Inflammation in the joint's synovial fluid causing pain and functional limitations.
- Traumatic Arthritis: Arising from injuries causing damage to the knee cartilage, leading to long-term complications.
While knee joint replacement is commonly recommended for individuals aged 60 and above, specific cases may involve younger adults experiencing traumatic arthritis, leading to partial knee replacement.
How Does an Orthopedic Surgeon Decide if You Need Knee Replacement
An orthopedic surgeon conducts a comprehensive assessment to determine the necessity of knee replacement:
- Physical Examination: Evaluating knee functionality, including range of motion, stability, and muscle strength.
- Diagnostic Imaging: Utilizing X-rays, MRIs, or CT scans to assess bone integrity and soft tissue condition within the knee joint.
When surgery is deemed necessary, the surgical approach and prosthetic selection are meticulously tailored based on several critical factors:
- Patient-Specific Considerations: Age, weight, activity level, knee anatomy, and overall health profoundly influence the surgical technique and choice of prosthetic components
This customized approach ensures optimal outcomes, considering the individual’s unique physiological characteristics and health conditions.
What are the Risks of the Procedure
Knee joint replacement is a transformative procedure that significantly reduces pain and enhances patient mobility. Doing so improves the quality of life and knee functionality in daily activities.
The procedure offers substantial benefits:
- Pain Reduction: Mitigating chronic knee pain, facilitating better movement, and restoring knee function.
- Enhanced Mobility: Enabling patients to engage in various activities with increased independence and self-care capabilities.
While complications are uncommon, potential risks associated with knee joint replacement include:
- Nerve Damage Risk: Minimal possibility of nerve damage during surgery.
- Post-Surgical Complications: Chances of post-surgical infections, blood vessel issues, and blood clot formation.
- Scar Tissue Formation: Occasional development of scar tissue within the knee post-surgery.
Specific to knee joint replacement, there are additional considerations:
- Prosthetic Component Risks: Potential for wear or loosening of the metal or plastic prosthetic components over time.
- Range of Motion Limitation: Possible decrease in knee joint range of motion following the replacement procedure.
How to Prepare for Knee Joint Replacement Surgery
Preparation for knee joint replacement entails comprehensive planning to ensure a smooth post-surgery phase. This includes arranging the necessary aids for mobility, accommodating home settings, and organizing transportation and assistance for daily tasks.
- Mobility Aid Arrangements: Weeks of reliance on walkers, crutches, canes, or wheelchairs post-surgery necessitate specific home accommodations. This involves securing safety aids like bath chairs, creating a convenient living space on the ground floor to avoid stair climbing, and implementing a toilet seat riser for comfort and accessibility.
- Transportation Planning: It is essential for the patient to make arrangements on who will drive them home after surgery.
- Assistance Planning: Additionally, planning who will assist them in the future with cooking, cleaning, shopping, laundry, and even bathing becomes crucial during the initial recovery phase.
Around two weeks before the procedure, your healthcare provider conducts a comprehensive health assessment encompassing:
- Medication Review: Assessing medications, particularly those impacting blood thinning or immune suppression.
- Consultations with Specialists: Coordinating with specialists to ensure patient safety concerning other medical conditions.
- Lifestyle Modifications: Advising cessation of smoking and alcohol consumption due to their impacts on oxygen supply and blood clotting.
Moreover, participating in pre-surgery physical therapy rehabilitation becomes pivotal:
- Pain-Free Strengthening Exercises: Engaging in exercises to strengthen muscles without exacerbating pain.
- Mobility Aid Practice: Familiarizing oneself with mobility aids for post-surgery mobility support.
The patient is commonly instructed to fast for eight hours before the scheduled surgery, usually starting at midnight.
What to Expect During Surgery
Knee joint replacement surgery typically spans 1-2 hours. It involves specific procedural steps conducted under either general or regional anesthesia.
The patient is either 1.) put under general anesthesia, rendering them unconscious throughout the procedure, or 2.) regional anesthesia is administered to numb the lower part of the body while the patient remains conscious.
The surgical process includes several key stages:
- Incision: A precise incision is made over the knee, allowing access to the joint area.
- Cartilage and Bone Preparation: Remove damaged cartilage and bone sections to create a suitable space for prosthetic components.
- Prosthetic Placement: Implant specially designed prosthetic parts onto the bone ends to replicate joint functionality.
- Meniscal Cartilage Replacement: Utilization of a plastic component to replace damaged segments of the meniscal cartilage.
- Kneecap Adjustment: Reshaping the kneecap if necessary to ensure compatibility with the new prosthetic joint structure.
- Closure: Suturing or stapling the incision site and applying appropriate dressing to facilitate healing.
This surgical procedure aims to restore the knee joint’s functionality, alleviate pain, and enhance the patient’s overall mobility and quality of life.
Recovery After Surgery
Following the procedure, patients often require an overnight stay in the hospital to recover from surgery and anesthesia effects.
The patient is treated with passive range-of-motion exercises before being taught how to move safely in and out of bed without stressing the replaced knee joint. In short distances (such as inside the hospital room or in a nearby hospital corridor), the patient is guided with their mobility aid on how to bear no weight on the affected knee.
Some cases may necessitate a rehabilitation center stay to ensure safe and independent daily activity execution before going home.
The recovery period typically spans 4-12 months, contingent upon factors like age, pre-surgery physical condition, and concurrent health conditions.
Pain Management
- Medications: Pain and anti-inflammatory medications are prescribed. Blood thinners may be prescribed to mitigate clotting risks.
- Ice Therapy: The application of ice aids in alleviating post-surgery pain and reducing swelling.
- Elevation and Compression: Elevating the knee above heart level and elastic compression minimize swelling.
Wound Care
- Incision Care: Maintaining cleanliness and dryness of the wound is crucial. Discussions with healthcare providers guide dressing changes, bathing timelines, and specific incision care protocols.
- Suture/Staple Removal: Scheduled follow-up visits include the removal of sutures or surgical staples.
Physical Therapy Rehabilitation
- Home Exercises: Prescribed post-surgery exercises aim to enhance knee strength, expand range of motion, and improve balance.
- Physical Therapy Sessions: Regular appointments over a few months facilitate pain and swelling management while gradually allowing weight bearing on the affected knee through essential movements like walking and bending.
Things to Avoid During Recovery Until Your Healthcare Provider Confirms It is Safe to Do So
In the recovery phase following knee replacement surgery, refraining from certain activities is essential:
- Driving Restriction: Avoid driving due to potential impacts on the knee when getting in and out of the car.
- Work Resumption: Postponing work duties until clearance from the healthcare provider for safety and appropriateness.
- Incision Wound Care: Preventing the incision wound from getting wet during the initial two weeks post-surgery to mitigate potential complications.
- Avoiding Falls: Minimizing falls or impacts on the knee area to prevent additional injury.
When to Call Your Healthcare Provider
It’s crucial to contact your healthcare provider if you encounter:
- Incision-related Issues: Inflammation, swelling, or discharge of pus from the incision site or persistent bleeding.
- Fever Concerns: A temperature of 101°F or higher, indicating potential infection or other health concerns.
- Increased Pain: Heightened or unusual pain around the incision area requiring immediate attention and evaluation.
Will the Knee Joint Replacement Last, or Will It Need to be Replaced?
Knee joint replacement surgeries have shown remarkable longevity, with more than 90% of patients experiencing sustained improved knee function for 10-15 years and, in some cases, even up to 20 years.
However, beyond this period, the prosthetic knee replacement may encounter issues such as loosening or wearing out, necessitating potential re-surgeries. Regular follow-up appointments become crucial to assess the alignment and condition of the artificial joint.
To prolong the longevity of knee replacements and minimize stress on the prosthetic joint, patients are advised to engage in specific activities:
- Low-Impact Exercises: Engaging in activities like walking, swimming, or cycling helps maintain fitness levels while exerting minimal stress on the artificial joint.
- Avoidance of High-Impact Activities: Running or jumping can strain the hip joint replacement, potentially accelerating wear or complications.
See our dedicated page to learn more about Joint Replacements.