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Center for Advanced Joint Replacement

Frequently Asked Questions About Knee Replacement

What is arthritis and why does my knee hurt?

In the knee joint, there is a layer of smooth cartilage on the lower end of the femur (thighbone), the upper end of the tibia (shinbone) and the undersurface of the kneecap (patella). This cartilage serves as a cushion and allows for smooth motion of the knee. Arthritis is a wearing away of this smooth cartilage. Eventually it wears down to bone. Rubbing of bone against bone causes pain, swelling and stiffness.

What is a total knee replacement?

A total knee replacement is really a cartilage replacement with an artificial surface. The knee itself is not replaced, as is commonly thought, but rather an artificial substitute for the cartilage is inserted on the end of the bones. This is typically done with a metal alloy on the femur and plastic spacer on the tibia and kneecap (patella). This creates a new, smooth cushion and a functioning joint that does not hurt.

What are the results of total knee replacement?

Knee-replacement surgery has a high rate of success in eliminating pain and restoring range of motion; 90-95 percent of patients achieve good to excellent results.

When should I have knee-replacement surgery?

Your orthopedic surgeon will decide if you are a candidate for the surgery. This will be based on your history, examination, X-rays and response to conservative treatment. The decision will then be yours.

Am I too old for this surgery?

Age is not a problem if you are in reasonable health and have the desire to continue living a productive, active life. You may be asked to see your personal physician for an opinion about your general health and readiness for surgery.

How long will my new knee last, and can a second replacement be done?

We expect most knees to last more than 10–15 years. However, there is no guarantee, and 5–10 percent may not last that long. A second replacement may be necessary.

Why do knee replacements fail?

The most common reason for failure is loosening of the artificial surface from the bone. Wearing of the plastic spacer may also result in the need for a new spacer.

What are the major risks?

Most surgeries go well, without any complications. Infection and blood clots are two serious complications that concern us the most. To avoid these complications, we use antibiotics and blood thinners. We also take special precautions in the operating room to reduce risk of infections, such as wearing "space suits," which are full-head and -body operating garments that are exceptionaly sterile. The chances of acquiring an infection or developing a blood clot are 1 percent or less.

Should I exercise before the surgery?

Yes. You should discuss preoperative physical therapy and exercise options with your surgeon. Exercises should begin as soon as possible.

Will I need blood?

You might need blood after the surgery. You may donate your own blood, if you are able, or use the community-blood-bank supply.

When will I be able to get out of bed?

Your surgeon may request that you get out of bed the day of your surgery. The next morning you will get up, sit in a chair or recliner and walk with a walker with help from the staff.

How long will I be in the hospital?

Most knee-replacement patients will be hospitalized for three to four days after their surgery. If you need more time for rehabilitation, other options may be available to you.

How do I make arrangements for surgery?

After your surgeon has scheduled your surgery, the Center for Advanced Joint Replacement case manager will contact you.

How long does the surgery take?

We reserve approximately two to two-and- a-half hours for surgery. Some of this time is taken by the operating room staff to prepare for the surgery. The surgery itself may take as little as 30 minutes.

What are my anesthesia options?

You may have either general anesthetic, which most people call "being put to sleep" or a spinal anesthetic. The choice is between you and the anesthesiologist.

Will I have pain after surgery?

Yes, but we will keep you comfortable with appropriate medication. Generally most patients are able to stop very strong medication within one day. The day of surgery, most patients control their own medicine with a special pump that delivers the drug directly into their IV. Your surgeon will discuss with you what pain control option is best for you.

Who will be performing the surgery?

Your orthopedic surgeon will perform the surgery. A physician's assistant often helps during the procedure.

How long and where will my scar be?

The scar will be approximately 6–8 inches long. It will be straight down the center of your knee unless you have previous scars, in which case your surgeon may make the incision along the prior scar. There will be some numbness around the scar. This will not cause any problems.

Will I need a walker, crutches, or cane?

Yes. Until your muscle strength returns after surgery, you will need a walker, a cane or crutches. Your equipment needs will be determined by the physical therapist and ordered for you by the Center for Advanced Joint Replacement case manager and delivered to you before you leave the hospital.

Will I need any other equipment?

Other equipment is available, such as a three-in-one bedside commode. A tub bench and grab bars in the tub or shower may also be necessary. Your home equipment needs will be evaluated and arranged while you are in the hospital. If needed, you will also be taught by an occupational therapist to use adaptive equipment to help you with lower-body dressing and bathing.

Where will I go after discharge from the hospital?

Most patients go directly home when discharged. The physical therapist will be scheduled to come to your home three times a week. You should check with your insurance company to see what rehabilitation benefits you are eligible for.

Will I need help at home?

Yes. For the first several days or weeks, depending on your progress, you will need someone to assist you with meal preparation, housekeeping, etc. If you go directly home from the hospital, family or friends must be available to help. Preparing ahead of time, before your surgery, can minimize the amount of help required. Having the laundry done, house cleaned, yard work completed, clean linens put on the bed and single-portion frozen meals will reduce the need for extra help.

Will I need physical therapy when I go home?

Yes. Physical therapy will continue after you go home with a therapist in your home or at an outpatient physical therapy facility. The duration and type of therapy varies with each patient. We will help you with these arrangements before you go home.

How long until I can drive and get back to normal?

The ability to drive depends on whether surgery was on your right leg or your left leg and the type of car you have. If the surgery was on your left leg and you have an automatic transmission, you could be ready to drive within two weeks. If the surgery was on your right leg, your driving might be restricted as long as six weeks.

When will I be able to get back to work?

We recommend that most people take at least one month off from work, even if your job allows you to sit frequently. More strenuous jobs will require a longer absence from work.

When can I have sexual intercourse?

The time to resume sexual intercourse should be discussed with your surgeon. The Center for Advanced Joint Replacement has a guide on resuming sexual intercourse and will give you a copy at your discharge instruction class.

How often will I need see my doctor after surgery?

Your first post-operative office visit will be two to four weeks after discharge. The frequency of follow-up visits will depend on your progress.

will my activites be limited after surgery?

Yes. High-impact activities such as contact sports, running, singles tennis and basketball are not recommended. Injury-prone sports such as downhill skiing are also dangerous for the new joint. You are encouraged to participate in low-impact activities such as walking, dancing, golfing, hiking, swimming, bowling and gardening.

Will I notice anything different about my knee?

Yes. You may have a small area of numbness to the outside of the scar, which may last a year or more and is not serious. Kneeling may be uncomfortable for a year or more. Some patients notice some clicking when they move their knee. This is the result of the artificial surfaces coming together and is not serious. Depending on the amount of stiffness you have before surgery, you may not regain full flexion (bending) or extension (straightening) of the knee.

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