Knee replacement is a surgical procedure for replacing the knee joint with an artificial prosthesis.

During the procedure, the ends of the shin and thigh bones are replaced with high quality metal components, while the cartilage is replaced with a high density polyethylene pad that has the same shock absorbing function.

Materials

Materials used in knee replacement prostheses must be compatible with the human body. It must be tough and capable of bearing weight.

Some of the materials that may be present in a knee prosthesis:

  1. Cobalt-chromium alloys – used for components that need to slide, e.g. the head of the femoral stem
  2. Oxidized Zirconium – combines the strengths of ceramic and metal and is bio compatible and more abrasion resistant than cobalt-chrome
  3. Ultra high molecular weight polyethylene is used as the cushioning material
  4. Cross-linked polyethylene is a new plastic that is just as tough and is relatively new to the market.

Pre-surgery planning

Medical planning

Dr van der Plank will work with you to determine which prosthesis on the market will best suit your lifestyle, age, height and weight. The materials used will also be considered for each individual case.

Preoperative x-rays, a complete medical and surgical history, a physical exam and a comprehensive list of medicines and allergies (especially metal and medication allergies) will be required at least two weeks before the surgery.

You will be required to undergo a complete physical exam by a physician in the days preceding the surgery to ensure you are physically able to undergo the procedure. Any existing infections must be cleared before surgery to reduce the risk of infection.

You may be asked to stop some medications in the days before surgery, particularly blood-thinning agents like warfarin.

Stop smoking to avoid any post-operative lung problems and to promote healing.

New global protocols for joint replacement surgery

Some major medical aids and private hospitals belong to ICPS (Improved Clinical Pathways Services). Discovery also has a global fee arrangement which applies to primary joint replacement. Both of these are programmes that regulate every aspect of your joint replacement, from the anaesthesia to the number of days spent in the hospital.

The anaesthetic of choice for a joint replacement is an epidural with conscious sedation. While this might sound scary, it improves the speed of recovery after the operation. Speak to your anaesthetist if you have any concerns.

If your medical aid is part of ICPS, or if you don’t have help at home, it is recommended that you book a place at a subacute (step down) facility for an additional 4-5 days post hospital discharge. Here you will get help in the form of wound treatment and physiotherapy.

Planning at home

Prepare your home before you go into surgery to make life easier when you return.

  1. It is of major importance that there is someone to take care of you when you get home as you will not be able to drive for some weeks after the operation and you will need assistance with many daily routines.
  2. Move all things you frequently use to between waist and hip height to eliminate the need to bend
  3. Eliminate small rugs or floor coverings that may cause you to slip
  4. Prepare a room on the ground floor to sleep in if your bedroom is on an upper floor

Items that can be useful

  1. Anti-slip mat in the shower
  2. Railing on the bathroom wall to help with entering and exiting the shower
  3. An extension grabber to pick up items from the floor – long braai tongs are useful
  4. A long-handled shoe horn or stocking aid to help put on the shoes and stockings

Items to pack for hospital

  1. Closed anti-slip shoes without laces
  2. Comfortable clothing (loose fitting and elasticated pants are ideal)
  3. Comprehensive list of all medications by trade name
  4. X-rays if available
  5. Medical aid details
  6. Entertainment (books, magazines etc)
  7. Walking aids if you use them.
  8. Personal care items
  9. Do not take money or valuables