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FAQs and Documents

Knee Replacement FAQs and Documents

Answers to the most common questions about knee replacement surgery.

Frequently Asked Questions About Knee Replacement

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.

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.

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.

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.

Age is not a problem if you are in reasonable health and have the desire to continue living a productive, active life. Your surgeon will ask you to be evaluated by a physician for an opinion about your general health and readiness for surgery.

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.

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.

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.

You should discuss preoperative physical therapy and exercise with your surgeon.

Rarely do patients need blood after the surgery.

You will be able to get out of bed the day of your surgery.

Most knee-replacement patients will be discharged the day of surgery. If you need more time for rehabilitation, other options may be available to you.

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

We reserve approximately three to three-and-a-half hours for pre-operative preparation, surgery and recovery.

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

Yes, but we will keep you comfortable with appropriate medication. We begin by managing your pain with pills following surgery and can give intravenous medication as needed. Your surgeon will discuss with you what pain control option is best for you in the hospital and at home.

Your orthopaedic surgeon will do the surgery. A physician’s assistant often helps during the procedure.

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 may be some numbness around the scar. This will not cause any problems.

Yes. You will start with a walker until your muscle strength returns after surgery. Your outpatient physical therapist will advance you to a cane when appropriate. Your equipment needs will be determined by the physical therapist and ordered for you by the Center for Advanced Joint Replacement care coordinator and delivered to you before you leave the hospital.

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.

The majority of patients go directly home when discharged.

Yes. In the first several days or weeks after surgery, depending on your progress, you will need someone to assist you with meal preparation, housekeeping, etc. Family members 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.

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

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.

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.

The time to resume sexual intercourse should be discussed with your surgeon.

Two to four weeks after discharge, you will be seen for your first post-operative office visit. The frequency of follow-up visits will depend on your progress and your surgeon.

You are encouraged to participate in low-impact activities such as walking, dancing, golfing, hiking, swimming, bowling and gardening. 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 your new joint. 

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.

Contact Us

To find a surgeon near you, call 800-693-2273.

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