Dear Dr. Garner,

I’m about to have knee replacement surgery and I am quite scared. It’s my first-ever operation. I’m otherwise in good health, although slightly overweight. Could you help me to be less scared?

Knee Replacement
Fears in Flatbush

Dear Knee Replacement,

While any surgery has risks, having knee replacement can be very rewarding and is a safe operation.

It seems like more and more people are having this surgery, perhaps as a result of the aging Baby Boom Generation.

Knee replacement surgery is usually performed after other measures, such as medication or walking supports, are no longer helpful. The first knee replacement was performed in 1968 and about 581,000 surgeries are now performed each year so you are in good company.

Some of the major reasons for knee replacement include: Arthritis from overuse of the joint, rheumatoid arthritis in which the body actually attacks the joint in error and causes it to break down, and post-injury problems, in which a knee fracture or severe tear of the ligaments damage the joint, limiting function.

Whether to have a replacement or not should be carefully reviewed with input from your family and physician. Some symptoms that might help you to decide include:

• Severe knee pain that limits your everyday activities.
• Moderate or severe knee pain while at rest, day or night.
• Chronic knee inflammation and swelling that does not improve with rest or medications.
• Knee deformities in which there is a bowing in or out of the knee.
• Knee stiffness and inability to bend and straighten your knee.
• Failure to obtain relief from medications or physical therapy.

The last item is really important.  You will know when knee problems cause such pain or limitation of your activities that your life is being adversely affected.

While most patients undergoing surgery are age 60 to 80, there are more and more patients selected at younger ages.

It is important to keep in mind that the surgery will give you a dramatic reduction in knee pain and increase function, but will not make you a super athlete or allow you to do more than you could before you developed the knee problems.

Knowing what to expect regarding the actual procedure is helpful in alleviating some fears.

On the day of the procedure, you will be admitted to the hospital. An anesthesiologist will interview you to discuss the anesthesia to be used. It is usually general anesthesia and you are asleep during the surgery. However, you may be offered either spinal or epidural anesthesia in which you will remain awake, but your legs will be numb.

The procedure takes about two hours.  Many different types of designs and materials are currently used in total knee replacement surgery so you should discuss your options with your orthopedist. After surgery, you will be moved to the recovery room where you will remain for one to two hours.

As an alternative to total knee replacement, your doctor may decide to do a more limited procedure, known as unicompartmental knee replacement.  This is used to replace only a certain part of the knee. It might be considered if the damage is limited to a specific area of the knee. The rehabilitation with this type of surgery is much faster and the hospitalization is shorter. Once again, this is something to discuss with your doctor.

Some doctors use an approach known as minimally invasive knee replacement. The incisions are smaller, rehabilitation is quicker and there is less pain.

It seems to work best in those who are non-obese with reasonable motion without major deformity in the knee.

The complication rate for knee replacement is low, and serious complications such as knee joint infections occur in fewer than 2% of patients.

Blood clots into the leg veins are the most common complication of knee replacement surgery.  Your surgeon will instruct you regarding prevention methods, which may include elevation of your legs and exercises to increase circulation, as well as support stockings and medications to thin your blood.

Knee replacements should last 10 to 15 years. The success of your surgery depends on how well you follow your surgeon’s instructions at home during the first few weeks after surgery.

Weight loss is very desirable and can improve your chances of success. You mention that you are slightly overweight, so this should be a goal for you. It is important to be in the best shape possible to give the procedure the best chance for success. If you smoke, you should stop, since smoking can increase your chances of getting a wound infection and slows your recovery.

You can exercise to strengthen your upper body prior to the procedure. This will help you to get around after surgery when using crutches.

After surgery you will need to participate in regular light exercise to maintain the proper strength of your new knee. You should take precaution to avoid falls.

You should notify your dentist that you had a knee replacement and should be given an antibiotic before all dental surgery for the rest of your life.[hr] Dr. Steven Garner is a Fidelis Care provider who is affiliated with New York Methodist Hospital, Park Slope. He also hosts “Ask the Doctor” on The NET, Tuesdays at 8 p.m. on Channel 97 Time Warner and Channel 30 Cablevision.