computer guided or computer assisted knee surgery (cas)

What is Computer Guided or Robotic Assisted Knee Surgery?

During Knee Replacement, the surgeon uses special saws to remove the damaged parts of the knee, guided by local anatomic landmarks which allow him to position cutting jigs. The cuts made with the saws establish the alignment of the prosthesis, which in turn affects how well the repaired knee will move, and how long it will last.

In Computer Guided or Robotic assisted surgery, digital technology is used to enable the surgeon to position the cutting jigs more accurately compared to conventional techniques.

This enhanced positioning of the cutting jigs may improve the durability of the knee replacement, post-operative pain, recovery time and range of motion.

Knee Singapore

People who suffer extreme pain in the knees, and who are unable to move freely because of rheumatoid arthritis, osteoarthritis, trauma or birth defects have much to gain from computer assisted knee surgery. Because they have had no relief from therapy, cortisone injections or anti-inflammatory medications, many of these sufferers may consider CAS in treating their knee pain.

If you have any peculiar bone deformities or already have a prosthesis in place, CAS might also be the procedure for you.

While the same types of prosthesis used in non-CAS procedures are used during computer guided knee surgery, tools for Computer Assisted Orthopaedic Surgery (CAOS), also known as Surgical Navigation or Image Guided Surgery, are widely and routinely used today.

These tools include 3D image-guided and non-image-based navigation systems, intraoperative visualisation devices, and robotics. Navigation systems may also be used prior to surgery to collect patient data that will help the surgeon prepare for the procedure itself.

Patient-matched instrumentation may also be used before surgery where software is used to plan the entire procedure to help ensure that the process goes smoothly. This instrumentation takes exact measurements of the bones to calculate the exact size of the prosthesis to be implanted.

During surgery, a camera captures images of the knee, while software integrates the images with data such as anatomic landmarks of the knee and leg for the surgeon’s guidance. Both actual and virtual images may be used.

The accelerometer is another CAS tool which detects motion and velocity, and allows electronic devices, including those used in medicine to track orientation as well as movement. The usefulness of accelerometer-based navigation systems in knee surgery has been shown in a study which also acknowledges the systems’ accuracy and the significantly less blood loss involved in their use.

Although CAS increases accuracy during surgery, there is still the possibility of errors such as those in the computer and tracking system when placing markers. Overlying cartilage and soft tissue might cause the bone to be missed, and the navigation might malfunction if there is dirt on the camera or reflectors.

Inaccuracies might also occur in situations where the pins holding the trackers in place may move, such as when the patient has severe osteopenia. Since the cutting guides alone are navigated during surgery, the surgeon might make an error by bending the saw blade while re-sectioning the bone.

Though the bone re-sectioning may be accurate, varying degrees of thickness in applying the surgical cement might lead to overall misalignment.

CAS also bears the risk of blood loss, femur or tibia fractures and fat embolism due to the placement of alignment rods and arrays. Drills and pins used during the procedure may likewise break. And because CAS extends the procedure time by up to 20 minutes, the prolonged exposure increases the risk of infection.

There is also the risk of delayed recovery in the quadriceps or the muscles in front of the thigh because of femoral array placement. Note, however, that complications arising from using CAOS are very rare.

When considering computer guided knee surgery, bear in mind that CAOS is still evolving and studies of the full extent of its capabilities and possible complications are still being conducted. The time and care you would spend on choosing a surgeon for a delicate procedure therefore doubles when it comes to choosing a CAS-proficient surgeon.

Find out whether the surgeon you have in mind has the necessary experience and training in the use of CAOS systems. The orthopaedic surgeon must likewise be able to forego the use of CAOS in the event of a sudden glitch or computer error during the procedure.

If patient-matched instrumentation is to be used, a standing X-ray of your knee will have to be taken along with an MRI scan. This enables the creation of an actual model of your bones which will guide the surgeon in removing the exact amount of bone during surgery, which in turn helps to ensure correct alignment.

Meantime, get in touch with the physical therapist you will be working with after surgery and focus on exercises that will strengthen your core and increase your range of motion. Make sure you take in enough protein to help your body deal with the stress of surgery and to help lower the risk of infection.

If you are anxious about your upcoming procedure, talk to your surgeon about the possibility of taking medication to help you relax, or try meditation.

Knee Singapore

People who have undergone CAS are usually up and about on the very same day, which already goes a long way towards facilitating the healing process. Commit to physical therapy after the procedure and make time for it with a consistent schedule. Biking and swimming are recommended as you work on building muscle strength in your upper body as well as your legs. Also pay careful attention to your post-surgery nutrition by increasing your intake of water and protein.

Pain is your body’s way of telling you that something is not right. Don’t just brush it off and risk the chance of comprosing your movement and interupting your daily activities. Get it checked today for the right intervention the soonest possible time. Book your appointment with Dr. Dutton, here.