Knee Arthroplasty

Using special instruments, the worn surfaces at the end of the thighbone are removed. The bone is then shaped to prepare for a new covering that is most commonly made out of metal. The top of the shinbone is prepared in a similar way. The worn surface is removed, and a new metal tray is placed on top of the remaining bone. This tray holds a hard plastic spacer that will become the new shock absorber between the smooth metal coverings. Your surgeon may also replace the back of the kneecap with a new plastic surface. Near the end of your surgery, your surgeon will attach the new metal and plastic coverings to the ends of the bones and the back of the kneecap. This can be done with bone cement where the new knee is essentially glued to the bones. This can also be done without cement with certain knee replacement implants that can be press-fitted tightly into the bones and affix to them naturally.

Either way, your doctor wants to secure the new knee so you can get back on your feet as soon as possible. When the implant is in position and all of the supporting muscles and ligaments are working well, your surgeon closes the incision with stitches or staples.

The procedure will take about approximately 2 hours to complete the operation.

The surgery can allow you to return to full activities with a healthy knee, including participating in your favorite sports without the use of a brace. The pain and stiffness are completely alleviated. You do not experience any instability in which the knee gives away. In short, your independence returns, and you can enjoy a better quality of life.

You may be a candidate for Total Knee Replacement if 

• You have a severely damaged, arthritic knee that limits your mobility and function
• You are older than 55
• You are in generally good health, and conservative measures fail to improve your symptoms.
• You are suffering from knee problems associated with osteoarthritis, rheumatoid arthritis orand other degenerative conditions such as osteonecrosis — a condition in which obstructed blood flow causes your bone tissue to die.
Moreover, you may undergo the surgery if you are suffering from the following:
• Severe knee pain that limits your everyday activities, including walking, climbing stairs, and getting in and out of chairs. You may find it hard to walk more than a few blocks without significant pain and you may need to use a cane or walker.
• Moderate or severe knee pain while resting, either day or night
• Chronic knee inflammation and swelling that does not improve with rest or medications
• Knee deformity: a bowing in or out of your knee
• Knee stiffness: inability to bend and straighten your knee
• Failure to obtain pain relief from nonsteroidal anti-inflammatory drugs. These medications, including aspirin and ibuprofen, often are most effective in the early stages of arthritis. Their effectiveness in controlling knee pain varies greatly from person to person. These drugs may become less effective for patients with severe arthritis.
• Inability to tolerate or complications from pain medications
• Failure to substantially improve with other treatments such as cortisone injections, physical therapy, or other surgeries
 Recommendations for surgery are based on a patient's pain and disability, not age. Total knee replacements have been performed successfully at all ages, from the young teenager with juvenile arthritis to the elderly patient with degenerative arthritis.

 

Your surgery can be successful with your help when you follow your orthopaedic surgeon's instructions at home during the first few weeks after surgery.
Wound Care: You will have stitches or staples running along your wound or a suture beneath your skin on the front of your knee. The stitches or staples will be removed several weeks after surgery. A suture beneath your skin will not require removal.

Avoid soaking the wound in water until the wound has thoroughly sealed and dried. The wound may be bandaged to prevent irritation from clothing or support stockings.

Diet: Some loss of appetite is common for several weeks after surgery. A balanced diet, often with an iron supplement, is important to promote proper tissue healing and to restore muscle strength.

Activity: Exercise is a critical component of home care, particularly during the first few weeks after surgery. You should be able to resume most normal activities of daily living within 3 to 6 weeks following surgery. Some pain with activity and at night is common for several weeks after surgery. Your activity program should include:
• A graduated walking program to slowly increase your mobility.
• Resuming other normal household activities such as sitting and standing and climbing stairs.
• Specific exercises several times a day to restore movement and strengthen your knee. You probably will be able to perform the exercises without help, but you may have a physical therapist help you at home or in a therapy center the first few weeks after surgery.
• Driving usually begins when your knee bends sufficiently so you can enter and sit comfortably in your car and when your muscle control provides adequate reaction time for braking and acceleration. Most individuals resume driving approximately 4 to 6 weeks after surgery.

Before deciding to undergo the surgery, you should first understand the benefits and the complications of the surgery. Then, you should look for a board qualified surgeon. Consult with your surgeon and inform your doctor regarding:

• Your relevant medical history. An injury that occurred decades ago may be relevant, as are prior surgeries and non-surgical treatments like physical therapy and medicines. Your surgeon also needs to know about other medical conditions that could affect surgery.
• All the medicines you take. This is especially important for people who take several types of medicine. Your surgeon needs to know about all pills, creams, injections or other forms of medicine that you are taking. Be sure to discuss over-the-counter pills (aspirin, decongestants, etc). And don’t forget about vitamins and nutritional supplements.
• Any allergies you may have
• Any previous tests such as X-rays, lab tests, etc.
• Your lifestyle, the activities you enjoy, and how osteoarthritis is affecting you physically and emotionally.
You may ask your surgeon the following questions:
• Can knee replacement surgery relieve my pain and stiffness?
• Am I a good candidate for knee replacement?
• What type of knee replacement do you use?
• What are the benefits and risks of knee replacement surgery?
• How long does recovery and rehabilitation take after surgery and what can I expect?
• What activities could I participate in after I recover?
• Do you use the knee replacement that can bend and rotate, offering more natural movement?

If you decide to have knee replacement surgery, you may be asked to have a complete physical examination by your family physician several weeks before surgery to assess your health and to identify any conditions that could interfere with your surgery.

The evaluation and recommendations may include:

• Your knee and leg should not have any skin infections or irritation. Your lower leg should not have any chronic swelling.
• You may be advised to donate your own blood prior to the surgery. It will be stored in the event you need blood after your surgery.
• Tell your orthopaedic surgeon about the medications you are taking. He or she will tell you which medications you should stop taking and which you should continue to take before surgery.
• Although the incidence of infection after knee replacement is very low, an infection can occur if bacteria enter your bloodstream. Treatment of significant dental diseases (including tooth extractions and periodontal work) should be considered before your total knee replacement surgery.
• A preoperative urological evaluation should be considered for individuals with a history of recent or frequent urinary infections.
• Home Planning: The following is a list of modifications that can make your home easier to navigate during your recovery:
o Safety bars or a secure handrail in your shower or bath
o Secure handrails along your stairways
o A stable chair for your early recovery with a firm seat cushion (and a height of 18 to 20 inches), a firm back, two arms, and a footstool for intermittent leg elevation
o A toilet seat riser with arms, if you have a low toilet
o A stable shower bench or chair for bathing
o Removing all loose carpets and cords
o A temporary living space on the same floor because walking up or down stairs will be more difficult during your early recovery

There are two common types of anesthesia used during knee replacement surgery: general anesthesia, where the patient is put to sleep, and regional anesthesia, where the patient is numbed below the waist, typically with an epidural. The type of anesthesia you will receive depends on your situation as the patient, as well as your surgeon's and anesthesiologist's recommendations.

The risks and complications associated with the surgery are:

• Deep Vein Thrombosis: This risk of clot formation in leg veins can be minimized by giving blood thinning medication after Total Knee Replacement surgery.
• Infection: The risk of infection is less than 1% and pre-operative antibiotics are given to prevent this from happening.
• Pain and Stiffness: Occasionally this problem occurs if you are significantly overweight or have diabetes. This may require a manipulation under anesthesia or a revision surgery.
• Nerve and vessel damage: It is unlikely that any major nerve or vessel will be damaged the total knee replacement procedure. It is, however, very common to have a small area of numbness over the outer side of your knee where a superficial skin nerve is always cut during the surgery.
• Failure of plastic prosthesis: The prosthesis may fail due to the plastic wearing out and it may require revision.
• Excessive bleeding and fluid build up around the joint. This may require drainage or may settle spontaneously.
• Excessive scarring: Some skin will scar up significantly at the site of incision.
• Major medical complications such as heart attack or stroke occur even less frequently.
• Chronic illnesses may increase the potential for complications.
• Drainage and/or foul odor from the incision
• Fever (temperature of about 101 degrees Fahrenheit or 38 degrees Celsius) for two days
• Increased swelling, tenderness, redness and/or pain

When your surgery is over, you will be taken to the recovery room. A nurse will care for you and monitor your condition as your anesthesia wears off. You may experience some symptoms during this time such as blurry vision, dry mouth, nausea, chills and perhaps some pain. These can be controlled by medications. After recovering from the anesthesia, you will be asked to do some simple breathing and moving activities. These activities help to prevent possible post-surgical complications, such as developing blood clots in your legs. After the surgery, you will be advised to avoid some types of activity, including jogging and high-impact sports, for the rest of your life. With normal use and activity, every knee replacement develops some wear in its plastic cushion. Excessive activity or weight may accelerate this normal wear and cause the knee replacement to loosen and become painful. With appropriate activity modification, knee replacements can last for many years. The goals of the surgery are to:
• Improve your muscle strength
• Increase the movement in your knee joint
• Protect your new knee joint
• Return to most of your normal activities Your surgeon, nurses and therapists will teach you how to use your new knee joint as you sit, stand, walk and carry out your daily activities. The timeline is tailored to fit your needs.

BHT 390,000-470,000