Total Knee Replacement Patient Information Handout

Dr. Steven Krywulak, BSc., M.D., FRCS(C)

Which patients are considered candidates for knee replacement?

Patients with painful arthritic conditions of the knee are usually appropriate candidates. Most commonly, knee replacements are performed on patients with osteoarthritis. Rheumatoid arthritis and post-traumatic arthritis are the next most common conditions resulting in knee replacement. The timing of the surgery is based on the severity of a patient’s symptoms. Most surgeons prefer that patients try all of the non-operative treatments available before proceeding to major surgery. Pain should be severe enough to be adversely affecting a patient’s quality of life. Pain at rest or at night indicates advanced disease. If simple activities of daily living are difficult or impossible because of knee pain, you are likely a candidate. Knee replacement is typically done in patients over 60 years of age but occasionally a patient may be a candidate in their 50’s or even more rarely in their 40’s.

What factors might exclude a patient from being scheduled for a knee replacement?

All patients must be fit medically for a major surgery. For example, a patient having a heart attack in the 6 months prior to surgery would not be a suitable candidate. Patients with other serious medical conditions may be excluded. Any patient with an active infection in the knee or elsewhere in the body would not be an appropriate candidate. Many patient factors must be considered and ultimately the surgeon must use his or her judgment as to whether to proceed forward with knee replacement.

What kind of results can I expect from my knee replacement surgery?

The goal of this procedure is to produce a pain free joint that functions well for activities of daily living and results in a meaningful improvement in patient quality of life. This result is achieved in 85% or more of cases. Some patients may have some minor aching in the knee after surgery but are greatly improved from their pre-operative status. This operation is not generally done to improve motion in a stiff knee. Although some motion may be gained at surgery, stiff knees often remain stiff but become pain free. Deformities such as knocked knees or bowed legs are corrected at the time of surgery resulting in a straighter appearing leg.

What are the risks and complications associated with knee replacement surgery? Knee replacement is not without risk. A patient must carefully consider the risks and benefits of surgery prior to giving informed consent. The following list includes the most commonly encountered complications of knee replacement surgery. They are divided into major and minor complications. Major complications can result in loss of life or limb. Minor complications can vary in severity from those causing significant difficulty to those causing minor inconvenience to the patient. No list of complications can include every known possible adverse event. If you have any further questions or concerns, be sure to ask your surgeon.

Major Risks - heart attack -stroke -pulmonary embolism - infection - bleeding requiring transfusion - allergic reaction to the anesthetic/antibiotic

Minor Risks - nerve injury causing numbness or weakness - knee stiffness -blood clots in legs - postoperative confusion -pneumonia

Patients are routinely given antibiotics to prevent infection and blood thinners to help prevent blood clots/pulmonary embolism. It is important to stop your anti-inflammatory medication a week prior to surgery to prevent increased bleeding unless you are taking Celebrex. If you are unsure, about this, simply ask your doctor. Aggressive physiotherapy is important to prevent knee stiffness and strengthen leg muscles. Most complications can be successfully treated with little or no impact on the final result for the patient.

Note: Most patients can expect swelling in the knee and foot for 3-6 months after surgery. Compression stockings can aid in the removal of swelling.

How painful is this procedure?

Most patients find knee replacement to be quite painful, especially for the first week. Patients are placed on long and short acting pain killers by injection or by mouth in hospital. By the third or fourth day, most patients are on pills and most will go home on these pills. Not all patients tolerate these medications well and this can make pain control challenging. The majority patients will have the most of their pain resolve by 6 weeks post-operatively. Some patients may take a full three to six months or more before their comfort level improves completely. Everyone responds differently and a lot of patience is required by patients in the post-operative period.

How long will I be in hospital after surgery?

Typically, most patients are in hospital for 2-3 days. If a patient requires a longer stay to recover, they may be transferred to a rehabilitation or transitional unit for further care. Due to hospital bed shortages, stays longer than 4 days are avoided whenever possible so that other patients do not have their surgery cancelled due to lack of beds on the ward. It is the responsibility of the patient to anticipate their needs following surgery and make arrangements for whatever is necessary to assist in a timely discharge. Will I need physiotherapy after surgery?

Yes, all patients will be seen by the physiotherapy team while in hospital. On discharge, patients are encouraged to see a physiotherapist to assist with their knee motion. Outpatient physiotherapy is somewhat limited at the hospital but enquiries can be made to access this service. Many patients will choose to see a physiotherapist in the community, but this service is not covered under the provincial health plan and is prohibitively expensive for some patients. Patients who can’t make it out of their home may arrange to have a home physiotherapist visit them postoperatively. This is covered under provincial health care but the number of visits you will receive is also limited. All knee replacements bend fully in the operating room. Any loss of motion is due to scar tissue formation. Patients that do not bend their knee for the first few weeks after surgery may be prone to significant loss of knee motion. Therefore, it is imperative that patients bend their knees after surgery even though it hurts.

What restrictions will I have after knee replacement surgery?

You will be permitted to shower over the wound by the second day in hospital. Bathing is not permitted until 5 days after the staples have been removed and the incision must be completely healed. Staples come out on Day 10-14 typically. Keep the wound clean and dry. Most patients can take full weight through the knee immediately, but usually require crutches or a walker until they are more stable. You may want to rearrange furniture or sleeping arrangements in your home to accommodate a walker and avoid stairs. You may require a chair in the shower or other assistive devices. Driving is not permitted for 9 weeks if the right knee is done and 6 for the left. You should be confident in using the leg to brake in an emergency. Return to work depends on the type of work done. Six weeks for return to a desk job and 3 months for other types of employment are general guidelines. Mobility will be restricted after surgery and arrangements for personal care, bathing, meals etc. should be made before surgery if possible. You can walk as much as you like. Sexual activity is permitted as soon as comfortable for the patient. It is possible that airport metal detectors will sense your knee prosthesis. No identification cards are necessary and most patients will make it through security without issue.

What activities can I do once I am fully recovered from surgery?

The purpose of this procedure is to help patients become more active, therefore we do encourage activity. However, high impact activities are not recommended as they may significantly decrease the lifespan of the implant, necessitating revision surgery. The following list serves as a guideline, but each case must be individualized to the patient. If you have questions, ask your surgeon. How long will my knee replacement last?

No one can predict this for sure. Individual patients vary in size, weight and the demands they place on their implants. Certainly, patients under the age of 65 will place increased demands on their implants creating concerns about longevity. Typically, a total knee replacement can be expected to last 20 years minimum. In lower demand patients, they may last 25 years or longer. Some patients will require x-ray follow-up every few years, especially if they are under 60 when they have their surgery. If an implant fails, it is much easier to revise the implant if the problem is detected early on before the knee becomes painful. At Kelowna General hospital, we use high quality knee components made by Zimmer. For younger patients, or those concerned about lifespan of their implants, upgraded premium implants are available at an increased cost. Most do not require these but if your surgeon thinks you are a candidate he will discuss this with you. If you want to enquire further about this, simply make an appointment. The upgrade involves the plastic liners only. Every patient gets the same metal components.

Joint replacement and metal allergies?

True metal allergies are rare. Most people will note rash with cheap jewelry or glasses. It is not known if patients will react to their implants. The offending metal is often nickel. Some components will have a small amount of nickel in them. If you think you have a metal allergy, it is worth bringing this to the attention of your surgeon. We do have some components that are nickel free and will use them if we think it is indicated.

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Dr. Steven Krywulak