Total Knee Replacement

"Sup tulang" will never be the same again...

Those are the bone cuttings from my mother's knee replacement procedure yesterday. As you may or may not have known, my mum had a total knee replacement procedure done on her left knee. She has had knee pain for many years but the past few years have been very bad. She could no longer bend her knee fully as her knee joint bones were already in physical contact, reducing the degree of movement. My mum had a fatal combination of low bone density (calcium deficiency), a curved tibia (a genetic trait I also inherit) and slight overweightness. These factors have caused excessive pressure on the outer (right hand side of the diagram below) causing that part of the knee joint to wear away. Normally the cartilage would act as the "lubricant" in the knee joint, separating the two knee bones but constant rubbing has worn this layer away. Just like teeth, once cartilage is gone, you won't get it back, so my mother was left with no other option than a total knee replacement. She has put this off for too long anyway.

I must admitt, coming into the operation, I did not know what the procedure was going to be like and what the implants would look like. I had always pictured a hip replacement which looks very different. So, below is how the knee replacement looks like:

Knee Illustration - Total Knee Replacement


Below are the steps the surgeon does to the knee during the procedure. On the left is he damaged joint. The surgeon first cuts away the worn out bone surface and shapes the surface to match the inside of the implants. It is only then the implants are screwed in like so.


Once the procedure is complete and the implants are in, this is how it should look like inside:

File:PTG F.jpegFile:PTG P.jpeg

The doctor has already asked my mum to start her physio therapy today, beginning with making movement with a machine. He says that a full recovery will be expected in a month or so. Then it will be back in the operation theatre for the other knee joint! We are quite lucky that my sister works at Prince Court Medical Centre and her employee benefits include healthcare (capped at RM50k per year, we have to pay 10% of the operation cost though) for one parent as long as she is unmarried. Same benefits as me but my policy does not cover parents if I'm unmarried. =(

Lessons from this:

1) Health is something worth investing in as all the money in the world is useless if you are unhealthy.
2) Healthcare is a worthwhile employment benefit that should be valued by the younger generation seeking to start a career. Most young people overlook this important benefit and look at gross pay only. It's only when something bad happens that they realise the cost of medical care these days isn't cheap.
3) It's worthwhile purchasing healthcare takaful at a young age (to keep premiums/contributions low). If you plan to take it at a later, advanced age you have the risk of the insurance/takaful company either not covering the sickness you already have or them not willing to cover you at all. The premium/contribution will be significantly higher too!

Anyways, for more info on a total knee replacement please read the article below written my a UKM specialist.  


Total Knee Replacement

Why Does My Knee Hurt?
Your knee joint is made up of three bones. Your thigh bone (femur) sits on top of your shin bone (tibia). When you bend or straighten your knee, the rounded end of your thigh bone rolls and glides across the relatively flat upper surface of your shin bone. The third bone is often called the kneecap (patella), which is attached to the muscles that allow you to straighten your knee. Your kneecap provides leverage that reduces strain on these muscles.
In a normal, healthy knee, the bone surfaces that come together at the joint are smooth and hard. A cushioning layer of tissue, called cartilage, prevents direct contact among these bones. This tough layer of tissue allows the three bones to move without creating friction or wear on the bone surfaces.

However, when this cartilage is damaged or worn away, your bones rub together causing friction, pain and, eventually, deterioration of the bone surfaces. The most common causes of damage to your cartilage are the various types of arthritis. There is no medication or treatment that will make damaged cartilage grow back.

What Is Total Knee Replacement?
In total knee replacement surgery, the parts of the bones that rub together are resurfaced with metal and plastic implants. Using special, precision instruments, your surgeon will typically remove the damaged surfaces of all three bones. The replacement surfaces will then be fixed into place.
The surface of the upper bone is replaced with a rounded metal component that comes very close to matching the curve of your natural bone. The surface of the lower bone is replaced with a flat metal component with a slab of ultra-high-molecular-weight polyethylene plastic to serve as the cartilage. The undersurface of the kneecap may also be replaced with a round disc made of the same polyethylene plastic.


How Will I Know If I Should Have Knee Replacement?
Your orthopaedic surgeon will perform a very thorough examination of your knee. This will include a test of your range of motion-how far you can bend and extend your knee. Your surgeon will also look deformities in your legs which may show up as conditions commonly called bowlegged or knock-kneed. You will be asked to walk, sit and perhaps go up and down a few steps.
Your surgeon will also ask you many questions to determine your medical history. You will be asked about injuries, infections and other disorders you have experienced in your life. Your surgeon will want to know what medications are you taking. And, of course, you will be asked to describe the pain in your knee.
Finally, your surgeon will take x-rays which will be used to further assess the condition of your knee joint. If you decide on total knee replacement surgery, these x-rays will also be used to help your surgeon select the best type and size of artificial knee.
Based on this examination, your surgeon will determine whether you are a candidate for total knee replacement. Although widely practiced, total knee replacement is a major surgical procedure and should only be considered when all other treatment methods have failed. There are more conservative alternatives which you and your surgeon may want to consider. These include medications or injections for pain and inflammation, physical therapy, or other types of surgery.
The final decision about whether or not to have total knee surgery will be yours, so you will want to understand the risks involved. There are potential complications both during and after surgery. Generally, these include infection, blood cots, pneumonia, prosthesis loosening, and nerve damage. Your surgeon can answer your specific questions about the risks.

What Is It Like To Have Knee Replacement Surgery?
Before Surgery
If you and your surgeon decide that total knee replacement is right for you, a date will be scheduled for your surgery. Several things may be necessary to prepare for surgery. For example, your surgeon might ask you to have a physical examination by an internist or your regular doctor.
Because blood transfusions are likely to be needed during your surgery, you may want to donate one unit of your own blood, or possibly two units if your surgeon feels it is needed. You can donate one unit per week before your surgery.
During Surgery
On the day of surgery, a small tube (intravenous line) will be inserted into your arm. This tube will be used to administer antibiotics and other medication during your surgery. You will be taken to the operating room and given anesthesia. After the anesthesia takes effect, your knee will be scrubbed and sterelized with a special solution.
The surgery will begin with an incision over the knee that will expose the joint. When the bones are fully visible to the surgeon, special, precision guides and instruments are used to remove the damaged surfaces and shape the ends of the bones to accept the implant.
The implants are then secured to the bones. It might also be necessary to adjust the ligaments that surround the knee in order to achieve the best possible knee function. When the surgeon is satisfied with the fit and function of the implants, the incision will be closed.
A special drain may be inserted into the wound to drain the fluids that naturally develop at the surgical site. A sterile bandage will then be applied, and you will be taken to the recovery room, where you will be closely monitored. Your surgery will likely take between one and three hours, depending on your individual circumstances.
After Surgery
As your anesthesia wears off, you will slowly regain consciousness. A nurse will be with you, and may encourage you to cough or breath deeply to help clear your lungs. You will also be given pain medication. When you are fully awake, you will be taken to your hospital room. Your knee will remain swollen and tender for a few days.

What Can I Expect After Surgery?
When you are back in your hospital room, you will begin a rehabilitation program that will help you regain strength, balance, and range of movement in your knee. This program will be designed specifically for you. It may include a machine, called a continous passive motion machine, that automatically moves your leg to help reduce stiffness.
Your physical therapist will help your perform appropriate exercises. About 24 hours after surgery, you will probably be asked to stand. Within the next 24 hours, you will begin to walk a few steps with the help of a walker.
You will be discharged as soon as your surgeon determines that you have recovered sufficiently. You can expect to stay in the hospital for about three days after your surgery. You may or may not be transferred to a nursing facility for a few more days, as determined by your surgeon. Your bandages and sutures will usuallybe removed before you leave the hospital.
At home, you will need to continue your exercises. Your physical therapist will instruct you about proper home care, and may continue to work with you.
Within six weeks after surgery, most patients are able to walk with a cane. You will probably feel well enough to drive car within seven to eight weeks after surgery.
In most cases, successful total knee replacement will relieve your pain and stiffness, and allow you to resume many of your normal daily activities. But even after you have fully recovered from your surgery, you will still have some restrictions. Normal daily activities do not include contact sports or activities that put excessive strain on your knees. Although your artificial knee can be replaced, a second implant is seldom as effective as the first.

Prof. Madya Dr. Suhail Suresh Abdullah
M.D (UKM), M.S Orth (UKM)
Senior Lecturer / Consultant Orthopaedic & Arthroplasty Surgeon
Knee and Hip Joint Replacement
(Special Interest in Minimal Access & Computer Aided Joint Replacement)