The following is a list of possible risks potential complications of total knee replacement surgery. These are merely possibilities which we feel patients ought to be aware of before deciding upon total knee replacement surgery.

• Anesthesia
• Blood Transfusion
• Blood Clots
• Infection
• Blood Vessels and Nerves
• Persistent Pain

Anesthesia
Total joint replacement is a major surgical procedure and requires either regional or general anesthesia. Regional anesthesia involves a spinal or an epidural administration of medicine that creates numbness below the waist. With general anesthesia, medication is given which circulates throughout the entire body and causes complete loss of consciousness. The risks of anesthesia are related to your general medical condition (not your age) and the function of vital organs such as the heart, the lungs and the kidneys. A thorough discussion of these risks can be conducted by an anesthesiologist. Although extremely rare, patients can die from complications related to anesthesia.

Bleeding / Blood Transfusion
There will be some bleeding as a result of the surgical procedure. For this reason, you will be asked to donate some of your own blood before surgery. If you should need a blood transfusion, you could then receive your own blood. A family member can donate blood for you before surgery (it takes 2 to 3 days to process the blood), but it may not match your blood type closely enough for you to receive it. Rarely, there can be bleeding complications related to surgery. In that case, it may be necessary to transfuse blood from the Red Cross blood bank. With any blood transfusion, there is always a small risk of a transfusion reaction or disease transmission. Major transfusion reactions are, fortunately, quite rare. The risk of transmitting HIV is about 1 in 150,000. To put this in perspective, you are actually more likely to be struck by lightning. The risk of hepatitis is greater than that of HIV, about 1 in 30,000 to 1 in 50,000. Fortunately, permanent liver damage is rare. Please refer to the section entitled "Planning for Your Surgery" for additional information regarding autologous, homologous and banked blood.

Blood Clots
Blood clots can form in the large veins of the legs and pelvis following major surgery, such as total knee replacement. It is possible for such a clot to break loose from the vein and travel to the heart. The clot can pass through the heart and into the lungs. This is called a pulmonary embolus. Rarely, a pulmonary embolus is fatal. In order to minimize the chance of the formation of blood clots, and subsequent pulmonary embolism, we routinely give anti-coagulation medicine following total knee replacement surgery. The anti-coagulation medicines carry a risk of increased bleeding, especially at the surgical site (inside the knee). The risk of increased bleeding is, however, more than counter-balanced by the protection against blood clots provided by the anti-coagulation medicine.

Infection
Infection can occur following any type of surgery. In order to minimize the potential for infection to occur at the time of surgery, antibiotics are given before surgery and for 1 to 2 days following the operation. Infection following total knee replacement is of special concern because of the prosthetic components. The prosthetic components have no blood supply and this makes them susceptible to infection. If the prosthetic components become infected, additional surgery is almost always required in order to treat the infection. Sometimes the infection can be treated without removing the total knee replacement components. In some cases, however, they may need to be removed in order to eradicate the infection. Intravenous antibiotics are generally administered for about 6 weeks in order to treat the infection. Once the infection is treated, new components can generally be implanted. If there is concern that the infection cannot be eliminated, then a knee fusion (arthrodesis) may be recommended.

The risk of infection persists for as long as the total knee replacement is in place. The most common way that a total knee replacement becomes infected is by spread of bacterial infection from another location in the body. Bacterial infections may be spread from the mouth because of a dental infection; from a urinary tract infection; as a result of pneumonia; from a skin infection; or even an in-grown toenail. It is very important that any bacterial infection be treated promptly in order to minimize the chance of spread to the total knee replacement. It is also recommended that antibiotics be taken before any dental procedure, although the need for special precaution during routine dental check-ups is controversial. If possible, any anticipated major dental work should be completed before total knee replacement surgery or deferred for at least four months after surgery. You should inform your dentist that you have a total knee replacement. Similarly, antibiotics should be given if you are going to have any type of invasive procedure such as an endoscopy or bronchoscopy.

Blood Vessels and Nerves
There are several major blood vessels and nerves around the knee. Rarely, a major blood vessel or nerve is injured during total knee replacement surgery. An injury to a blood vessel can usually be repaired at the time of surgery. Nerve injuries may not be recognized at the time of surgery. Nerve injuries associated with knee replacement surgery can result in numbness and weakness, usually around the foot. Such nerve injuries may or may not require surgical repair, and the nerve usually recovers over a period of several months, however, the injury is occasionally permanent.

Persistent Pain
While more than 90% of patients have complete or nearly complete relief of pain following total knee replacement, there are some patients with some persistent pain. In many cases, the pain resolves with time. In other cases, a specific cause for the pain can be identified and treated. This may involve the patella and occur with deep bending or forceful straightening of the knee. Sometimes this requires additional surgery. It should be recognized that there are many causes of pain and, rarely, patients can have pain even if the knee replacement is well-fixed and well-functioning.

Tn many ways, a total knee replacement is similar to a set of automobile tires. How long the knee replacement lasts is related to the type and amount of use, and not simply how long it has been implanted. A set of automobile tires can last for many years if the car is not driven very much. Alternatively, a set of automobile tires can wear out in less than one year if they are driven many miles over rough roads. This principle is applicable to total knee replacement.

Although it is anticipated that a total knee replacement will last for many years, some fail sooner than expected. The main causes of failure are loosening, wear, osteolysis and component breakage.

Fortunately, these occurrences are rare. Unfortunately, they can occur and generally necessitate additional surgery. A prosthetic knee component can loosen from the bone due to relative motion between the component and the bone. The intended use of a total knee replacement results in wear of the polyethylene tibial and patellar components. Just as small pieces of rubber wear off an automobile tire when it rolls, the intended motion of the knee replacement generates very small particles of polyethylene. These particles are released into the tissue around the joint. If enough particles are generated, they can cause inflammation. This type of inflammation can result in resorption of the bone around the total knee replacement. This type of bone resorption is called osteolysis and can necessitate additional surgery.

Although uncommon, it is possible to wear-out these plastic parts. Very rarely, a total knee replacement component actually breaks. This usually occurs because the component is no longer supported by bone because of bone resorption. Fracture of the bone around a total knee replacement can also occur and surgery may be necessary to stabilize the fracture.

Loosening, wear and osteolysis generally occur slowly over time. The patient may not initially experience any pain or other symptom indicating a problem. For this reason, it is generally recommended that all total knee replacements be evaluated with x-rays on a yearly basis. This way, problems can be detected and treated early and, therefore, more easily.

The following topics will assist you in planning for the day of your total knee replacement surgery :

• Informed Consent
• Blood
• Medications
• Weight Reduction and Home Exercises (Knee)
• Home Preparation
• Medical Evaluation
• Pre-operative Orthopaedic Examination
• What to Bring to the Hospital
• After Your Knee Surgery (Post-Op)

Informed Consent
It is essential that you fully understand the risks, potential complications and treatment alternatives related to joint replacement surgery. The physician will discuss these issues with you prior to surgery, usually at the time of your initial consultation. Separate "consent" forms will be presented to you by the physician's office and the hospital's admitting department for your signature. The physician will not perform surgery without a signed informed consent on file. Please discuss any concerns which you may have with the physician prior to surgery to ensure that you are making an informed decision regarding your health care.

Blood
You'll be asked to donate one or two units of your own blood before surgery. As with many surgeries, bleeding can occur during knee surgery and you may require a blood transfusion. There are several options available to replace the blood you lose during surgery and these include: 1) autologous blood; 2) directed donor blood; 3) banked blood; and 4) cell saver blood.

Autologous blood is your own blood that is set aside before surgery so that it is available during or after surgery if the need for a transfusion arises. Since the blood is your own, it has the advantages over blood from other individuals in that it is incapable of causing stimulation of antibodies to its contents (transfusion reaction). It also carries no risk of transmission of infectious diseases such as hepatitis or AIDS.

Depending on the number of units estimated to be needed for your surgery, you will be advised to begin donating blood in advance of the surgery. Your blood can be kept fresh for 42 days. The interval between blood donations should be no shorter than one week, and the last unit should be drawn no later than 5 days prior to surgery. Patients who weigh less than 110 lbs. are eligible to give smaller amounts (e.g., only 1/2 unit at each donation) and therefore may need to start donating earlier.

The procedure of drawing blood takes about one hour each time, although the first time will take about 15 minutes longer to complete the paperwork. You will be asked to rest for 15 minutes before leaving the donor center. You can drive an automobile if you feel perfectly well but should inform the nurse if you have any doubt. One week prior to when you begin your blood donations and during the donation period until surgery, it is advisable that you take iron (ferrous sulfate FeSO4) 325 mg and Vitamin C (ascorbic acid) 500 mg - 1 of each, three times a day with meals.

Blood can be collected at the hospital or if you do not live nearby, your blood can be donated at another blood bank and transferred to the hospital prior to your surgery. Do not cut the donation schedule too close because your donation schedule can be delayed if you become ill or your blood count becomes too low. This will not allow you to give the necessary number of units.

A special fee must be paid at the time the blood is drawn. These charges pertain even if the blood is not transfused. If you donate your blood at the hospital where the surgery will be performed, then you are usually not required to pay the fees at the time of donation as the charges are included as part of the hospitalization. Autologous blood donation has been highly successful, and in most instances has avoided the need for the use of homologous (another donor's) blood.

Designated Donor blood is donated from someone that you designate in advance, such as family members, relatives, or close friends. These can be arranged if you are unable to donate the appropriate number of autologous units before your surgery. However, the designated donors must have a blood type that is compatible and meet the strict donation criteria of the blood bank. These include no history of previous blood transfusions, hepatitis, or jaundice, no surgeries during the past 6 months, no anti-malaria medication in the last 3 years, no previous donations for 56 days, and age between 17 and 66 years (over 66 requires blood bank doctor's approval). A perfect match may be difficult to find, so your own blood is still the best and highly recommended. Further, designated donor blood has not been documented to be any safer than banked blood.

Banked blood (homologous blood) is donated by volunteers to local blood banks. The donors are thoroughly questioned and tested for potential transmissible diseases and the blood is carefully screened. There is a minimal risk of transfusion reactions. The risk of transmitting HIV is estimated to be 1 in 150,000 units of blood and the risk for hepatitis is estimated at 1 in 30,000 to 1 in 50,000.

Cell saver blood is your own blood that is collected during surgery and reprocessed by a special machine. This blood can then be given back to you during surgery. There are some limitations to this system and the blood cannot always be used. Therefore, other types of blood should also be available. Erythropoietin is a naturally occuring hormone that regulates the production of red blood cells in the human body. Recent advances in technology have provided the basis for the development and production of recombinant human erythropoietin, which is now available worldwide. It is a safe and effective method of increasing the blood volume prior to joint replacement arthroplasty for a selected population which cannot donate blood or accept transfusions because of religious beliefs (e.g., Jehovah's Witness).

Medication
If you are taking birth control pills, or anti-inflammatory medications such as aspirin, Indocin, Motrin, Feldene, Naprosyn, Voltaren, Lodine, etc., please discontinue their use at least one week prior to surgery. These medicines can cause increased bleeding. If you need pain relief, you can take Tylenol or your doctor can prescribe narcotic pain medication.

Weight Reduction and Home Exercises for the Knee
Keeping your weight down is not only good for your knee, it is good for your general health. You should make an effort to get "in shape" for surgery and, therefore, it is recommended that you begin a preoperative program of exercise (only if it is comfortable to do so). Easy isometrics (muscle tensing exercises) will help maintain the strength of your leg muscles in preparation for postoperative walking. The following exercises can be done in bed. Exercise each leg remembering to breathe normally throughout the exercise. Perform 2-3 times per day.

Gluteal Setting Exercise : Squeeze your buttocks together tightly, hold for ten counts. Relax. Repeat ten times.

Quadriceps Setting Exercise : Tighten the muscle on the top of your thigh by pushing the back of your knee down on the bed. Hold for ten counts. Relax. Repeat ten times.

Hamstring Setting Exercises : Keep the knee bent slightly. Push your heel down into the bed and then pull toward buttocks. Hold for ten counts. Relax. Repeat ten times.

Ankle Circles : With lower leg resting on a towel roll, move the ankle in a circle first in one direction, then in the other. Repeat ten times.

Ankle Pumps : Move the ankle up and down slowly. Repeat 10 times.

You will be using your arms often during the postoperative period while moving in bed and with the walker or crutches. Therefore, strengthening your upper body is also important. Exercises should include:

Pull-ups : While sitting in a chair, hold onto a bar that is overhead and raise your buttocks off the chair. Repeat ten times.

Reverse Push-ups : While sitting in a chair, place your arms at your side and hold onto the chair next to your buttocks. By straightening your elbows, lift your buttocks off the chair. Repeat ten times.

You can also do general strengthening exercises with small weights.

You may wish to consult with the hospital physical therapist before surgery to discuss these and other beneficial exercises.

Home Preparation
Preparing your home for post-operative recuperation is essential since you will be using either a walker or crutches. Begin home preparations at least a week in advance of surgery. You should try using a walker or crutches around the house making sure that important areas (bathroom, kitchen, bedroom) are easily accessible. You may need to rearrange furniture or temporarily change rooms for your convenience after your surgery. If possible, minimize the number of stairs you must climb each day. Remove all throw or area rugs that could cause one to slip. Bathroom modifications which may be helpful include a shower chair, gripping bars, flexible shower handle, non-slip floor surfaces or mats, soap bars with a string attached and a long-handled scrub brush. If you live alone, you may want to make arrangements to have a friend or relative stay with you for a short while after your surgery. Ask for help ahead of time to be sure that they will be there when you need them. This is especially useful in meal preparation, carrying various items such as plates and cups, putting on socks and personal hygiene. It may be helpful to wear shirts with pockets and/or to drape a small canvas or plastic bag draped over your shoulder for carrying smaller items. Occasionally, patients are sent to a rehabilitation facility after their surgery until they are stronger.

If you do not already have a disabled parking permit from the Department of Motor Vehicles, you should apply for a temporary permit several weeks prior to surgery. Our office can provide an application.

Medical Evaluation
Knee replacement surgery is a major procedure and care must be taken that you are in the best medical condition. You'll need to have a general medical evaluation by an internist in order to assess your health and determine your relative risk for anesthesia. The type of anesthesia is a decision made between you, your internist and the anesthesiologist. Your medical evaluation should occur two to three weeks prior to your surgery. Please arrange to have this physician send to our office, prior to your pre-operative orthopaedic examination, all test results as well as a note which clearly states that you may undergo the proposed surgery. Your surgery may be postponed if our office does not receive the test results and/or surgical clearance timely. If you do not have a regular medical physician, we can provide a referral.

Pre-operative Orthopaedic Examination
You may be required to undergo a pre-operative orthopaedic examination in our clinic. If so, this appointment is usually scheduled on the day before surgery. At this time we will review the proposed surgery with you and answer any last minute questions you may have. We will also review your medical evaluation, laboratory tests, x-rays, and obtain any other tests or x-rays that are necessary. If you have blood transferred from another blood bank we will check that it has arrived. You will need to sign a surgical consent. Finally, you will be directed to the hospital's "Pre-Op" unit for pre-admission and instructions. The nurse will give you instructions for the evening before your surgery and show you where to report the morning of your surgery. If you do not live locally and wish to stay in the area on the night before surgery, please ask our office for assistance at the time you schedule surgery. The hospital may have a guest room available on a first-come, first-served basis at nominal rates for your convenience which we can reserve for you or we can provide information regarding nearby hotels.

It is imperative that you not eat or drink anything after midnight (12:00 AM) the night before surgery. This helps to prevent potential nausea and vomiting from occurring during surgery which could cause complications.

What to Bring to the Hospital
The most important item to bring is a pair of comfortable, sturdy bedroom slippers with non-skid soles! The Physical and Occupational Therapy Department will provide a walker or crutches, raised toilet seat, reacher and other equipment as needed. To enhance your postoperative therapy, a knee-length robe or gown is recommended. Do not bring floor-length robes as they make walking difficult. Ladies may want to bring a camisole or lightweight cotton shirt to wear under the hospital gown for added warmth. Leave all jewellery at home! A package containing personal care items is provided although you may want to bring your own hair brush. Loose fitting pyjamas or sweats are useful to wear on the way home as are a comfortable pair of shoes. Program guides for television viewing are available. Of course, good reading material may help pass the time more quickly! If you take medication for any condition other than your arthritis, then be sure to bring it with you to the hospital, or bring a list of your medications and dosages with you to the hospital.

• The Day of Surgery and Postoperative Course
• Physical Therapy
• Follow-up Examinations
• Medication Issues