About Knee replacement
A total knee replacement, also called total knee arthroplasty, is a surgery performed to correct the problem associated with a worn out knee. The knee joint comprising femur (thighbone) and the tibia (shinbone) may be damaged from medical conditions, injuries, or from repetitive motion. As a result, the knee is less able to cushion stress to the joint and pain with movement or swelling may occur. Because cartilage (a soft tissue like a cushion that absorbs stress and allows the joint to glide smoothly) cannot fully repair itself, your orthopaedic surgeon may recommend knee replacement surgery to be performed.
The Procedure
Knee replacement surgery involves either resurfacing the entire joint (total knee arthroplasty), or repairing the damaged parts (partial knee arthroplasty). During the procedure, the damaged parts are removed and replaced with implant(s) made of metal, ceramic, or plastic. The procedure is performed at a hospital in the operating room. Anaesthesia will be administered so that either you sleep throughout the surgery (general anaesthesia) or so that you are numb from the waist down (spinal block). An incision, or cut, will be made on the front side of the knee and the damaged knee will be replaced with prosthesis (artificial joint). The surfaces of the joint are reshaped to accommodate the prosthesis. The orthopaedic surgeon takes great care to test the fit and alignment of the prosthesis during the procedure to ensure that the prosthesis is a good fit for the body. If the prosthesis fits correctly, the parts are secured to the thighbone, kneecap, and shinbone, and a new joint is formed which is mobile, pain free and long-lasting.
Are you a candidate for Total Knee Replacement?
Here are factors to consider:
- Is the pain severe enough to restrict work, recreation and ordinary activities of daily living?
- Have you unsuccessfully tried other non-operative procedures such as injections and physical therapy?
- Do you have knee deformity (bow legged or knock kneed) that hinders normal function of the knee?
- Are you unable to tolerate pain after taking medications?
- Do you need to take medication regularly?
- Is there significant stiffness in the knee?
- Are the joints damaged with arthritic conditions, such as osteoarthritis, rheumatoid arthritis or post-traumatic arthritis?
If you answered YES to any of these questions, then Total Knee Replacement is worth exploring.
Post Op Recovery
Rehabilitation begins as soon as possible after your operation. You return to the ward in the afternoon/evening and being assessed by a physiotherapist to see if you are able to stand and take a few steps with your new knee with their help. When you can walk well without limping and feel confident, you can stop using your walking aids. You will be given compression stockings to wear or have a pump which inflates pads to compress your feet. These help to maintain circulation and prevent blood clots after your operation but do not restrict you moving your legs. There will be some pain, swelling and bruising which is normal. Usually you start going to the washroom independently with some support by 2nd or 3rd day and stair climbing with support starts at around the same time. It is important to move your knee as soon as possible after the operation unless your surgeon or physiotherapist tells you not to. This will minimise stiffness, pain and swelling, and reduce the formation of scar tissue. Regular physiotherapy after your surgery will help you to get the most out of your new joint. Physical activity will help you have a faster recovery and will get your blood moving. This will also reduce your risk of developing a blood clot. Walking is a good way to build up and maintain the strength in your leg muscles. By 4 to 6 weeks after your surgery, you should be walking with more strength and be able to walk longer distances
Though traditional knee replacement method is considered to be a very successful method of undertaking the surgery, however, new technology is gearing towards making the patient the centre of advances in knee replacements. We start using a novel technique of personalised or customised knee replacements as we understand that both patients and their individual anatomy are unique. This technique involves the patient undergoing a preoperative CT or MRI scan, depending on the implant being used. The images from the scans are sent to the prosthesis manufacturer. From the images, computerised technology is utilised to provide the optimal size of the implants needed. Specific customised cutting blocks are then created, which are then sent back to the surgeon for use at the time of the operation. The process has a lead time of around 1 to 2 weeks from the time of the scan. The result is that there is no requirement for estimation at the time of surgery, with more specific and accurate personalised bone cuts being made, which have been predetermined prior to the operation.
When the personalised knee replacement is combined with a rapid recovery protocol, which includes pain relief, immediate rehabilitation and mobilisation, this can lead to a more pleasant patient experience, with a shorter hospital stay.
Customised knee replacement benefits
- Reduces surgical steps
- Reduces instruments and trays
- Reduced cost
- Cuts are based on patients’ true mechanical axis
- Reduces blood loss
- Potential to decrease overall recovery time
Over the years we have learned that success in total knee arthroplasty is critically dependent on implant alignment. Literature has shown that revision rate is reduced and implant survivorship is increased in cases where the knee implant is in neutral alignment to the mechanical axis. Thus, implanting the knee close to the neutral alignment is extremely important to the overall implant success. Computer-assisted surgical techniques are designed to reduce the outliers, providing more consistent results in alignment. Throughout every step of the procedure, the surgeon is able to verify the intended results, with precision and accuracy that is displayed in-vivo.
The technology creates a 3D model of the patient anatomy with minimal time added to surgery. The computer recommends best implant fit and position before any bone cuts are performed, allowing the surgeon to plan the procedure moving forward. Surgeons are able to gather real time patient specific data to determine soft tissue releases and bone cuts, allowing optimal implant position according to the individual patient’s needs.
Computer assisted knee replacement benefits
- Allows the surgeon to intraoperatively customize the surgical plan
- Provides the precision and accuracy
- Planning is done dynamically during surgery
- Cuts are based on patients’ true mechanical axis
- Reduces blood loss
- Potential to decrease overall recovery time