Total Knee replacement Video



Patellofemoral Replacement Video



Revision Knee Surgery



Frequently Asked Questions

What is a knee replacement?

A knee replacement is an elective surgery, replacing the bottom end of the femur and the top end of the tibia with a man made device (prosthesis). The back surface of the patella is also commonly resurfaced. Total knee replacement is not a complete solution to the problem as they become loose with time and may need to be revised (which means another operation) within ten to fifteen years.

What are the benefits of a total knee replacement?

You do not have to live with a painful knee for the rest of your life. During this surgery your problem knee joint is replaced with an artificial joint (a prosthesis). After a total knee replacement, you can look forward to moving more easily and without pain.

What is the prosthesis made of?

These devices are combinations of metal and plastic and sometimes ceramic materials.

What is used to attach it to my bones?

They are fixed to the bone either using bone cement or by using a prosthesis with a rough surface, which relies on your bone growing on to the implant for long term stability. It may be reinforced with screws on the tibial side. In between the two components is a special plastic liner made out of polyethylene.

Who is offered total knee replacement as an option?

When you have arthritis on your X-ray and pain and stiffness from your knee joint cause:

  • Severe disability
  • Difficulty or inability to perform your job
  • Interference with your leisure activities
  • Interference with your walking or mobility
  • Difficulty putting on shoes and socks
  • Waking you at night despite non operative treatment such as drugs
  • Or when conservative treatment such as analgesia, anti-inflammatories, weight loss, physiotherapy and aids like crutches or a cane has failed.

Remember that it is an elective procedure and should only be performed when you are no longer prepared to put up with your pain and disability and understand the benefits versus the risks involved.

Is the procedure safe?

Knee replacement procedures have come a long way since their beginning in Ancient Egypt. They are now a very commonly performed procedure and advancements continue to be made.

However, there are risks in any operation. You can read about the general complications here. Some complications specific to total knee replacement are:

  • Infection
  • Fracture
  • Stiffness
  • Damage to nerves or blood vessels
  • Blood clots
  • Wound irritation or breakdown
  • Wear
  • Osteolysis
  • Damage to ligaments
  • Dislocation
  • Heterotopic ossification
  • Cosmetic appearance
  • Leg length inequality
  • Breakage of the implant

Your doctor can give you more information about these complications.

When can I go back to work?

Most patients return to sedentary jobs at 3-6 months after total knee replacement. It must be stressed to the patient before surgery that they may not return to manual labour after joint replacement. Any heavy manual job will result in premature loosening of the joint replacement and pain due to the increased stress on the joint replacement. Clerical or supervisory duties are suitable for a patient with a total knee replacement.

When will I be able to drive again?

When you feel comfortable using your leg fully. For most people, they feel comfortable driving after six weeks. Please also check with your insurance company as they may have specific rules on when you can drive after surgery.

When will I be able to resume sexual intercourse?

Sexual intercourse is allowed when the patient is comfortable but they have to be in charge of the positions used and any significant discomfort should result in the patient abstaining until they talk to their doctor.
In general, sexual intercourse occurs at around three to six weeks post operatively.

When will I be able to play sports?

Obviously, pounding sports are not good for joint replacement as they can wear the articulation. We recommend walking, bushwalking, swimming, stationary bike riding, doubles tennis and skiing on groomed runs if the patient is already a good skier. Jogging and heavy weights, although possible, will wear the joint prematurely.

Patient Instructions

Pre-Admission Clinic

You will be required to attend a pre admission clinic. Everything you need to know about what to do before, during and after your stay in hospital will be discussed at length at this clinic. Your doctor will also examine you and ask you questions, and you should let them know if you have any abrasions or pimples around the knee.

At this clinic the following will be attended to:

  • Blood tests

    You will have simple blood tests to make sure your blood count is normal and you have no other major medical problems. Because knee replacement is such a major operation with drilling and cutting involved there is a higher risks than in most operations of the health care team catching diseases transmitted by blood. For this reason, a sample of your blood will also be tested for AIDS and hepatitis. The results of this test can take up to two weeks.
  • ECG
    
A cardiograph of your heart will be taken to make sure you have no underlying cardiac problems. An ECG is non-invasive – no needles, just some stickers on your body that communicate to a machine through wires.
    X-rays
Your doctor may or may not require new X-rays of the knee he is operating on.
  • Urine sample
    
This is required to make sure you do not have a urinary tract infection. An infection anywhere before surgery e.g. infected toenail, skin lesion, throat infection, gum or dental infection, can greatly increase your chances of infection of the joint replacement following surgery. If an infection is found, it can be treated with simple antibiotics prior to surgery.

Pre-operative Instructions

Medications

  • Cease aspirin and anti-inflammatory medications (e.g. voltaren, feldene) 10 days prior to surgery as they can cause bleeding.
  • Cease any naturopathic or herbal medications 10 days before surgery as these can also cause bleeding
  • Patients taking blood thinners or those with diabetes will have special instructions but in general you should stop taking aspirin, Plavix (clopidogrel) and warfarin 5-10 days prior to surgery.
  • Continue with all other medications unless otherwise specified

Home Preparation

  • Arrange for someone to help out with everyday tasks like cooking, shopping and laundry
  • Put items that you use often within easy reach before surgery so you won’t have to reach and bend as often
  • Remove all loose carpets and tape down electrical cords to avoid falls. Make sure you have a stable chair with a firm seat cushion, a firm back and two arms
  • Make sure your shower or bath is safe and easy to get in and out of. Handrails, non slip mats and suitable stools to sit on are helpful for personal safety and comfort

The Procedure

  • The anaesthetist will see you before the surgery. They will discuss with you then if they are going to do a spinal, epidural or general anaesthetic.
  • After you are taken to the operating theatre, while you are still awake you are placed on the operating table and set up for surgery with a tourniquet placed around your thigh.
  • A urinary catheter will be placed in your bladder to measure your fluid balance during and after surgery.
  • A cut is made in the skin and underlying tissues to expose the knee.
  • Special instruments are used to make very accurate cuts in the bone to fit the prosthesis.
  • Trial components are put in first to make sure everything fits properly. The bone is then cleaned to remove debris.
The real components are then inserted with or without cement.
  • Drains are usually inserted.
  • The wound is then carefully closed in layers, the last being the skin.
  • A dressing is applied and you are taken to recovery.

After your Operation

  • Your leg will be bandaged from the groin to the toes.
  • Your fluid input and output is measured carefully. A drip in the arm will be used to give you fluid, replace blood during the operation and for antibiotics.
  • Pain is normal after the operation, but if your pain is not reduced be sure to tell the nurse. Pain medication may be injected into a muscle or delivered by IV into the blood stream.
  • Patient Controlled Analgesia (PCA) allows you to control your own pain medication. When you push a button, pain medication is pumped through your drip. PCA pumps can provide a steady level of pain relief and with their built in safety features, you will be assured that you will not get too much medication.
  • The drip, drains and catheter are removed on your surgeon’s advice at approximately 24 hours after surgery.
  • Blood will be taken 24 to 48 hours after the operation to check your haemoglobin and blood chemicals.
  • Your exercise regime will begin as soon as you are capable and this will continue during your stay in hospital and once you are at home. A physiotherapist will supervise this.
  • You will be discharged three to five days post-operatively, depending on your progress. In most cases you will be sent to a rehabilitation centre before you go home to have hydrotherapy and physiotherapy.
  • Sutures are usually dissolvable but if not, are removed at about 10 days.

Recovery

  • You will be in hospital for approximately five days. At Day 2 you will get up on a frame and then you progress to crutches and then a stick usually by four to six weeks.
  • After hospital, you will usually go to rehabilitation for one to two weeks. This will include aggressive physiotherapy and hydrotherapy.
  • When you leave hospital you will probably still require tablets for pain but no injections. Wean your medications down to paracetamol as soon as possible.
  • It is best to avoid anti-inflammatory medications for one week to avoid any possible bleeding.
  • You lose 60 to 80 percent of your pain by six weeks and 95 percent of your pain by twelve weeks. By twelve weeks you can usually walk as far as you want to.
  • Regaining movement early is extremely important, getting the knee straight is as important as bending. Do not put anything under the knee even though it feels comfortable as it prevents it from straightening.
  • People usually can return to work somewhere from eight to twelve weeks. Heavy manual work may take longer. Normally by three months you can play sports like golf, bowls, stationary bike ride, bush walk, doubles tennis and swim.