The knee joint consists of the connection (articulation) between the end of the thigh bone (distal femur), top part of the leg bone (proximal tibia) and the undersurface of the knee cap (patella). Arthritis is when the cartilage covering any one of those surfaces wears away. When the underlying bone starts to rub, this causes the pain associated with arthritis.   

Patients with knee arthritis often feel 

• knee pain with standing or walking for long periods of time
• knee stiffness limiting their ability to 
• straighten the knee during walking or 
• fully bending the knee while sitting in low chairs or on the floor.

Knee Arthritis can be caused by

• Osteoarthritis (wear and tear with age or obesity)
• Rheumatoid arthritis or other inflammatory arthritis
• chronic ACL tear (remote sports injury)
• previous fractures or other trauma around the knee
• Previous knee infection

The initial treatment for knee arthritis can include 

• Pain medication – unless you have liver problems, acetaminophen (Tylenol) is typically recommended, to start.   Many medical associations have recommended AGAINST using narcotics for arthritis pain, as this can risk addiction, without an improvement in pain.
•  Anti-inflammatory medication – ask your family doctor if you may safely take anti-inflammatory medication. Patient with a history of stomach ulcers, high blood pressure, or kidney disease should usually avoid these types of medication.
• Physiotherapy – visit a physiotherapist so that they can teach you a program focused on quadriceps, hamstrings and abductor strengthening that you can do at home on your own.  See your physiotherapist occasionally so that they can monitor your progress, correct your form, and add exercises to your program.  Even if you end up proceeding to knee replacement surgery, “Pre-hab” will help quicken your postoperative recovery. If you are being funded by extended health benefits and you are on a waitlist for surgery, be sure to save most of your benefits for after surgery.
• walking aids –  a cane or walker may help walking be more comfortable
• knee injections – a good non-operative option.  See section on injections
• Weight-loss, if necessary. If you are overweight, losing as little as 20 pounds can improve your knee pain.   Although exercise is important for strong muscles and heart health, diet is by far more important for weight loss.  Speak to your family doctor about diet resources.  You can get started with information regarding healthy eating at the Heart and Stroke Foundation of Canada

If non-surgical treatment does not adequately manage symptoms then total knee replacement can be considered. 

No amount of online information can replace a visit with an orthopedic surgeon to determine if you would benefit from a knee replacement.   This serves as a guide only.  Knee replacement is an option in patients who have evidence of knee arthritis and

• knee pain due to the arthritis that significantly limits walking or other everyday activities.  Knee arthritis is only one of the many causes of pain around the knee. (Other causes of knee pain include back issues, tendon, muscle, or other soft tissue problems.)
• tried non-surgical options that have not adequately helped with the pain/function
• good underlying health.  Patients who have had recent cardiac events, heavy smokers, poorly controlled diabetes, morbid obesity or dementia, are at high risk for complications after knee replacement surgery.
• Can commit to the physiotherapy program after surgery

In knee replacement surgery, your surgeon fits a metal cap to the end of the thigh bone (distal femur) and top part of the leg bone (proximal tibia).  A piece of plastic (polyethylene) is placed in between these two components.  Depending on the pattern of your arthritis, sometimes the undersurface of the patella is also resurfaced with a separate piece of polyethelyene.  The incision is made in the front of the knee.

Almost all patients receiving a knee replacement by Dr. Cayen are going home the same day of surgery.  Some patients with certain medical conditions stay overnight for monitoring and get a blood test the next morning.  Patients who stay overnight are usually discharged by noon.

Before your surgery, please plan to have some help you at home post-operatively.  Alternatively, please make arrangements to stay at someone’s place where they can help you for the first 3 days after your surgery.

In short, yes.  During the surgery itself however, you won’t feel pain (see Day of Surgery below).  Dr. Cayen uses local anesthetic during the procedure to help keep you comfortable. 

Humber River Hospital is now pleased to offer a local anesthetic bottle that patients take home after their knee replacement surgery.  This bottle is attached to a catheter that is placed into the thigh by our anesthesiologists prior to your procedure.  This special piece of technology infuses local anesthetic into your knee for 3 days after your surgery to help keep you comfortable.  You will be instructed to remove this catheter after 3 days.  -It’s as easy as removing a band-aid.

The local anesthetic during the surgery, the bottle described above and various medications prescribed by your doctor have helped our knee replacement patients recover with less pain (and less narcotic use) than before.

Dr. Cayen also recommends cryotherapy (an ice-machine) to help with pain control after surgery (See Preparing for Surgery section below).  Knee replacement surgery however is more painful than hip replacement surgery, and the recovery is slower.

Data from international registries suggest that 90% of knee replacements last 20 years, and 82% last 25 years. This is from a meta-analysis of registry data published in The Lancet in 2019.

Infection

The lifetime risk of a serious infection after a knee replacement is approximately 1%.  Some of these infections occur soon after surgery, but most occur months or years afterwards.  The treatment for serious (deep) infections includes revision surgery and IV antibiotics.  Skin infections (cellulitis) after knee replacement is more common and can be treated with oral antibiotics.  

People at higher risk for infection include patients with poorly controlled diabetes, patients with morbid obesity (BMI more than 40), patients who are immunocompromized  (eg HIV, lymphoma), or are taking immunosuppressant drugs, patients with peripheral vascular disease (poor circulation to hands and feet) and smokers.  An ongoing infection at the time of surgery from another source (eg active urinary tract infection, tooth abscess, diabetic foot infection can increase your risk of infection after surgery.  

In order to prevent infection, your surgeon will give you one dose of antibiotics through your IV in the operating room before your surgery.  You will get one more dose after your surgery.  Growing evidence suggests that numerous doses of antibiotics after your surgery does not prevent infection. 

The symptoms of infection include fevers, redness around the wound, persistent leaking from the wound, increasing pain in a previously well-functioning joint replacement.  If you think you are developing an infection around your knee replacement, call your orthopaedic surgeon’s office as soon as possible or go to your nearest emergency department.

Skin Numbness

Most patients experience a patch of skin numbness, about the size of their palm just to the outside of (lateral to) the incision site of the knee replacement scar.  This patch of skin numbness can decrease in size over months to years, but will not affect your function.  

Incomplete pain control

Knee replacement can help with 80-85% of knee pain associated with arthritis after 3 months of recovery, but doesn’t usually get rid of 100% of knee pain.  Most people still get some aches and pains in their knee replacement, even after recovery is complete.  

Knee stiffness

Immediately after total knee replacement, your knee will be stiff and painful to move.  It is of the utmost importance to work on moving your knee despite this discomfort in the first few days after your knee replacement.  Doing the exercises given to you by your physiotherapist immediately after your surgery will help you enjoy your knee replacement in the long run.  If you do not work on bending and straightening your knee after your surgery, your knee replacement can become permanently stiff.  Ideal range of motion after knee replacement recovery is 0 (completely straight) to 120 degrees.  After surgery, it is unlikely you will be able to squat all the way down such that your heel touches the back of your thigh.

Blood Loss

Some blood loss during knee replacement is normal.  Blood loss requiring a blood transfusion after surgery is rare unless you are anemic (low hemoglobin levels) before surgery.  You will be sent for blood work when you book your surgery to make sure that you are not anemic.  If you are anemic before surgery, we will refer you to our Patient Blood Management Coordinator who may suggest ways to build up your hemoglobin levels prior to your surgery.  The risk of requiring a blood transfusion increases if you are having both your knees replaced at once.

Blood Clot

Blood clots in leg veins can occur after knee surgery.  Your surgeon will prescribe a medication for you to take after your surgery in order to prevent blood clots.  If a clot develops in a deep leg vein (deep vein thrombosis – DVT) above the knee, it will need to be treated with stronger blood thinners.  Above knee DVTs need to be taken seriously because they can cause clots that go to the lungs (pulmonary embolus), which is a very serious condition.  If you have previously had a DVT, please let your surgeon know prior to your surgery.  

Component loosening

The metal components of the knee replacement are usually cemented to your bone during a knee replacement.  Over the years however, the bond can loosen, requiring a revision of the components.  Less common causes of early loosening include infection, morbid obesity and severe osteoporosis.

• Plan to go home the same day of surgery.
• Make plans to have someone stay with you at home for 2-3 days after your surgery (especially at night).  You may choose to stay at someone else’s house immediately after surgery.
• Start your discharge planning before you meet with Dr. Cayen. Please tell Dr. Cayen your discharge plan when you meet him.
• If you do not have a place where you can be monitored after your surgery, you may choose to consider respite care at a short-stay retirement home.
  • Respite care must be arranged by YOU well in advance of the surgery date.
  • Respite care is an out of pocket expense.
  • A sample list of respite care locations can be found here.

For final questions regarding your discharge planning, you may ask to speak with a Social Worker or our Orthopaedic Care Navigator.

Do not stop or change any medications before speaking with your doctor.  The information below is meant only to give you an idea of what to expect before your surgery.

Inflammatory Arthritis Medications

• Some medications for inflammatory arthritis (such as Rheumatoid Arthritis) may need to be stopped for a few weeks before and after your surgery.
• Some “Biologic” Drugs can increase the risk of infection around the time of surgery and can seriously affect wound healing.
• Let Dr. Cayen know if you are taking medication for Inflammatory Arthritis
• You will need to speak with your Rheumatologist before stopping these medications temporarily.
• A scientific review paper accessible by your Rheumatologist can be found here.

Blood Thinners

• You may need to stop taking those for up to 5 days prior to your surgery.
• Let Dr. Cayen know if you are taking blood thinners.
• Speak with your Family Doctor before stopping blood thinners temporarily.

Diabetic Medications

If you have diabetes, you may be seen by an internal medicine specialist prior to your surgery who will tell you which of your diabetes medications should be changed temporarily prior to your surgery.  You may need to speak with your Family Doctor or Endocrinologist before adjusting your medications temporarily.

Narcotics

• Narcotics for chronic knee pain or other chronic musculoskeletal pain is not recommended.
• Dr. Cayen suggests that you work with your prescribing physician to slowly lower or eliminate the use of narcotics for chronic joint pain.
• Patients who are taking narcotics prior to surgery have a more challenging course with pain control after surgery.
• Information for patients on opioid tapering can be found here: Opioid Tapering Information for Patients
• Information for physicians regarding opioid guidelines can be found here: Opioid Guidelines for physicians CMAJ 2017

Weight Control and Diet

• • Being overweight can put excessive forces through knee replacements and may lead to early loosening of the implants.  Scientific data suggests that if your Body Mass Index (BMI) is more than 40, you are at increased risk of infection after knee replacement.  Excessive weight can compromise optimal component position during surgery.   Decreasing your weight, if necessary can improve your knee pain prior to surgery and improve the speed of recovery after surgery.
  • Calculate your BMI here

• Although exercise is important for weight control, diet is by far more important.  Some things you can do to help with your diet include lowering overall portions, eating food high in protein and lower in carbohydrates, not eating after dark, not drinking beverages with calories (such as soft drinks or fruit juices) and creating a food diary.  Speak to your family doctor about a weight loss program, if necessary.  One resource for weight loss from the Heart and Stroke Foundation can be found here.

Smoking

Stop smoking at least 6 weeks prior to your surgery.  In addition to damaging your lungs and heart, smoking slows bone healing which is an important part of having the implants in joint replacement surgery bond to your bone.  Smoking will make your recovery from surgery take longer.  Smoking also increases the risks of poor wound healing and increases the risks of infection.  Resources for smoking cessation can be found here.

Diabetes

If you have diabetes, getting your blood sugars under control prior to your surgery is important.  Before your surgery, speak to your family doctor or endocrinologist about your “Hemoglobin A1c”.  If it is high, it might mean that your blood sugars are not under control.  Poorly controlled diabetes increases the risk of infection after knee replacement surgery.

Strengthening Exercises

Seeing a physiotherapist once or twice before your surgery to teach you quadriceps-strengthening exercises may be helpful to quicken your recovery after surgery.  The stronger you are before your surgery, the stronger you will be afterwards and the faster your recovery will be.

1. 2-wheeled walker.  – You will need a walker for 1-3 weeks after your surgery.
2. Cane.  – You will progress to using a cane after the walker.  You may need a cane until the 6-12 week mark.
3. Raised toilet seat. – Might be more comfortable for you for the first 12 weeks after surgery
4. Non-slip bath mat
5. Dr. Cayen recommends the use of a cold-compression device (cryotherapy) for pain control after your surgery.  This may be covered by many extended-health insurance policies.  Dr. Cayen’s administrative assistant will speak to you about cryotherapy prior to your surgery.

1. Do not eat or drink anything after midnight the night before surgery.  You should take the medications you have been instructed to take the morning of surgery with sips of water.  Do not take the medications you have been told to stop taking.Arrive at the Hospital 2 hours before your scheduled surgery.  You will be registered, then get changed into a gown.  You will have an intravenous line started and may be give some medications for pain and nausea.  You will then see our anesthesiologist who will discuss the anesthetic.  Typically, knee replacements are done with a spinal anesthetic in addition to nerve blocks in the leg.  Once in the operating room, you are given sedation through your IV, such that you are sleepy but no breathing tube is required.

You will wake up and recover initially in our Surgical Day Care (SDC), where you will complete your recovery, receive some medications and be seen by our physical therapists (PTs).  Our PTs will get you up walking in the SDC within a few hours of your surgery.   You will be allowed to put full weight on your leg after surgery.  When our PTs deem you’re safe for discharge home and your pain and nausea are under control, you will be discharged home with family or friends the same day of surgery.  You must arrange to get a ride to and from your surgery ahead of time.You will be discharged home with prescriptions for pain killers, a blood thinner and a prescription for post-operative physical therapy.  You may need a walker for approximately 2 weeks after your surgery.  You may need to use a cane up to the 6-8 week mark after your surgery.  Everybody’s recovery pace is different.  As long as you are improving week-to-week, you are doing well.

You will be instructed to unwrap the bulky dressing over your knee on the first day after your surgery.  It is then crucial for you to participate in the home exercises on your own immediately after surgery.  Our PTs will give you a list of exercises.  At your 1-2 week visit, Dr. Cayen expects his patients to be able to lift their heel off the bed without assistance (perform a “straight leg raise”) and be able to bend their knee to 90 degrees.

Our pharmacy will put together a combination of pain medications in a blister-pack for you to help manage your discomfort after surgery.  Inside this blister-pack will be non-narcotic medications that Dr. Cayen suggests you take as prescribed.  The contents of the blister-pack depends on each patient’s medical history.

Taking the blister-pack of prescribed pain medications will help lower the amount of narcotics that you need after your surgery.   Take the narcotic only as necessary, only if the blister-pack of pain medication is not adequate for your pain control.  Narcotic pain medication can make you constipated, drowsy, nauseous and can be addictive.  Many of our patients after hip and knee surgery don’t need any narcotics, if they take the blister-pack of pain medication as prescribed.

The anesthesiologist administer a special nerve block just prior to the knee replacement.  You will then take home a bottle which will deliver local anesthetic directly to the knee for 3 days after surgery through a thin tube (called a catheter).  The anesthesiologist will give you a call in the days after surgery to see if you’re having any trouble with the local anesthetic bottle.  You will be instructed how to remove the catheter from the thigh on the third day after surgery.  (It’s pretty simple: Pull out the tube, apply pressure with gauze for 2 minutes then apply a simple band-aid.)

You will also receive a blood thinner medication to help prevent blood-clot for one month, if you are not already taking a blood thinner.

You will see Dr. Cayen 1-2 weeks after your surgery in the Fracture Clinic.  He will check your wound and make sure you are doing your home exercises.  Dr. Cayen will check how well you can bend and straighten your knee, and see if you can do a “straight leg raise”.  Your staples will be removed.  Your subsequent two follow-ups with Dr. Cayen will be at approximately the 6 week and the 3-4 month mark after your surgery in the Fracture Clinic.  If you are feeling well at that point, no further follow up with Dr. Cayen is necessary unless concerns arise.  If you have concerns regarding your knee replacement, please give Dr. Cayen’s Administrative Assistant a call at (416) 479-8969 ext. 23005.

Before you leave the operating room, Dr. Cayen will place a water-proof bandage over your incision.  You can shower with this bandage on.  You will be instructed to take this bandage off 7 days after your surgery.  More information about the dressing can be found here.  You may replace the bandage with a strip dressing for showers, in order to keep the wound dry until the wound heals completely.  Do not submerge the wound under water in a tub or swimming pool until the wound is completely closed (usually around 3 weeks after surgery).

The success of a knee replacement is highly dependent on the physiotherapy you do after surgery. Your physiotherapist will teach you exercises that you will need to do at home. These include quadriceps strengthening as well as knee range of motion exercises. It is crucial that you do these exercises at home, despite the discomfort.  Some of these exercises can be printed here.

For right-leg surgery, you can drive once you are not using walking aids and are not using narcotics for pain control.

For left-leg surgery, if you are driving an automatic transmission vehicle, you can drive once you are no longer taking narcotics for pain control.  If you drive a standard transmission vehicle, the restrictions are similar to right-leg surgery.

You need to feel confident that you can hit the break with good force and reaction time before you return to driving.

Work

Return to work depends on the kind of job you have.

Sedentary/Desk job:  It is reasonable to take 8 weeks off of a sedentary job after knee replacement.  Many patients start working from home after a 2-3 of weeks (as long as they are not taking narcotics for pain).  Dr. Cayen suggests working not more than 2-3 hours per day during the first few weeks after surgery and to take frequent breaks.  Sitting for long periods of time after joint replacement surgery can theoretically increase the risk of blood clots.  Spend your first few weeks after surgery doing your physiotherapy and resting.

Walking Jobs: Typically patient can get back to an active job approximately 3 months after surgery.  When you do return to work, Dr. Cayen suggests return to work gradually, with graduated hours and graduated duties over a number of weeks.

Manual labour:  Historically, joint replacement surgery was reserved for the elderly and certainly those people who were not doing manual labour jobs.  We do not have long term data on the effects of manual labour on joint replacement surgery however heavy lifting does place large forces through the joint.  This could possibly lead to early loosening. Dr. Cayen does not recommend returning to a job requiring heaving lifting after joint replacement.  If your are currently able to perform your duties in a job requiring heavy lifting, perhaps a joint replacement is not right for you at this time. You might want to hold off on joint replacement until after you are no longer able to perform heavy lifting, or discuss with your orthopaedic surgeon.

Activities

Most patients experience an improvement in their daily activities after their rehabilitation from knee replacement surgery.  You are encouraged to resume non-impact activities after your recovery.  This can include, walking, cycling, elliptical training, swimming and golf.  Many patients have returned to light tennis, skiing and even non-contact ice hockey/skating after their rehab is complete.  As a general guide, if you can perform these activities without the risk of falling or loosing control (ie an expert hockey player or skier who takes it easy) before surgery, then you may train and eventually return to that activity.  Before you return to sport, it is imperative that your physiotherapist or athletic therapist guides your return to activity with a sport-specific exercise regimen, lest you risk injury.

It is not recommended that you return to high impact activities like jogging, running or jumping sports after joint replacement.  Such activities cause high forces through the joint and can theoretically lead to early loosening of the components.

For dental procedures, you do not need extra antibiotics above what is normally prescribed by your dentist. You should be in optimal dental health prior to your knee surgery. Infected teeth should be treated fully prior to your knee surgery. If you are approaching your scheduled regular dental cleaning, have that done prior to your knee surgery. Continue on your regular dental cleaning schedule after your knee surgery.

The Canadian Arthroplasty Society consensus statement for patient with total joint replacements having dental procedures can be found here. You may show this to your dentist

Travel

Vacation travel after knee replacement can be done as soon as 6 weeks post operatively. Although it is possible to travel before then, it is recommended that they be short flights and that you get up out of your seat hourly to move.

For those who must travel prior to 6 weeks after surgery, blood thinner medication is recommended and can be discussed with Dr. Cayen or your family doctor.

Note that your recovery and self-directed physiotherapy program should continue until approximately the 12-week mark.

Metal detectors at the airport

You will likely set off metal detectors at the airport. You do not need a note from Dr. Cayen or your family doctor regarding your joint replacement. Just let the security personnel near the metal detector know. They may ask you to go through the body scanner instead. Given how common joint replacements are, security personnel are accustomed to this issue.

A video on metal detectors with joint replacements from the American Association of Hip and Knee Surgeons can be found here.