Computer-Assisted Total Knee Replacement

Computer-Assisted Total Knee Replacement

With the advancing technology in the field of science and medicine, computers have been taking over the territory of orthopaedic surgeons too. Computers have been eliminating the guesswork during surgeries and help in performing surgery with utmost accuracy and precision. Even though the very first computer assisted knee replacement surgery was done way back in 1997, it hasn’t been made a daily practice anywhere across the world. Many countries are yet to bring in this technology into their everyday routine. In the UK and the USA, less than 3% of the hospital are using this method. Close to 6% of the practising specialists in France are using computer assisted method to help them with the total knee replacement. More Often than not it is said that Computer assistance during knee replacement surgeries are used as a marketing tool or as a gimmick for attracting more affordable patients. However the protagonists argue that it’s the improved accuracy which attracts them to use computers. Both parties however would agree that in certain special situations computers are almost inevitable while doing kne replacement surgeries.

What is computer assisted knee replacement surgery?

Computer assisted knee replacement surgery is a surgical method in which a computer helps a surgeon with the creation and display of images which shows the segments or parts of the knee that has been replaced and their relationship with the ligaments of the joints and the bones. There are two components involved in the computer: 

  • A camera that is designed to look at the joint and the limb and to create the picture of the same.
  • A computer program that helps in integrating the images that are produced with the surgical information aids the surgeon while performing the operation.

In addition to the above, the computers can also use CT Scan, MRI & Radiographic images to create other kinds of virtual images of the joints, including joints that are damaged. The surgeon feeds the information about the normal and abnormal anatomic marks of the limb and the joint into the computer and the camera. The information and the images needed to reconstruct the damaged joint or the limb is generated by the surgeon with the help of a computer.


How computers can assist in Total knee replacement?

The knee surgeons perform this procedure by using the recent methods of computer assistance. Each step during knee replacement surgery has to be precise and correct else it affects the next step and a step after that. In case one step goes wrong, the following steps will also go wrong. In Knee replacement surgery errors are going to be unforgiving. But with computer assistance, the surgeon can pre-plan his entire surgery on the computer generated model before executing this on the patient directly. In case the surgeon finds an error in the computer generated model, he can change it before he performs the surgery. Likewise, with computer navigation, the knee specialist can check the precision of each step before going on to the next step. With the right computer equipment and good amount of time, the end result is going to be a perfect fit. 


Indications for Computer Assisted Total Knee Replacement?

The most common knee problem requiring knee replacement in Asian countries related to the knee is osteoarthritis. The indications Total Knee Replacement surgery include:

  • Osteoarthritis 
  • Rheumatoid Arthritis
  • Trauma causing fracture
  • Ligament related injuries around the knee
  • Dysplasias
  • Ankylosing Spondylitis

Although computer assisted knee replacement can be performed in any of the above situations, it’s important to use this technology in the following conditions:

  • Knee arthritis associated with extra articular deformities 
  • Severe deformities associated with multiple joint and bone deformities 
  • For patients with Revision Hip Replacement Implants making it difficult to use conventional jig based knee replacement equipments
  • Dysplastic bones and joints with absent standard reference points  


How can patients benefit from Computer Assisted Total Knee Replacement?

Computer-assisted surgery expands the exactness and precision and gives the knee specialist real-time input during the medical procedure. This technique additionally decreases the mistakes, by making the knee surgeon aware of the potential complications before the procedure is performed. It gives the specialist the assurance to deliver the procedure with accuracy and control.


Advantages and Disadvantages of Computer Assisted Total Knee Replacement

The advantages of Computer assisted total knee replacement surgery are: 

  • Dynamic evaluation of distortion at any angle of flexion with the patella in situ instead of regular Total Knee Replacement where tensioning contraptions can be utilized in zero and 90° in particular. 
  • Calculation of delicate tissue pressure to give a perfectly adjusted knee.
  •  The accurate rebuilding of the mechanical limb axis. 
  • Reduced blood loss. 
  • Decrease in rate of fat embolism because of extra-medullary instrumentation (avoids intra medullary instrumentation).
  • Accuracy of information on soft tissue tension even in 1 mm and 1°. The knee specialist is given control, feedback, capacity to address mistakes and documentation required by Computer Assisted Surgery.

The disadvantages of Computer assisted total knee replacement surgery are: 

  • Computer Assisted total knee replacement surgery increase the operation time.
  • There are major possibilities of having a deep infection because of longer exposure time
  • A significant cost is required for the purchase of the machinery and maintenance of it.
  • The procedure is more complicated compared to other traditional methods of total knee replacement, there will be learning curve.
  • A surgeon needs to have practiced Computer assisted total knee replacement surgery a lot before they perfect it
  • There is a lack of evidence of the long term benefits of computer assisted total knee replacement.


Why are surgeons not using this technology routinely in most parts of the world?

In spite of the aforementioned advantages, most knee specialists are yet to use this innovation routinely. Some of the reasons are stated below: 

Risk of Infection: During computer assisted total knee replacement surgery, the patient is exposed for a longer duration compared to the other methods. In addition to that, additional equipment like pins and screws are used. This increases the risk of infection.

Prolonged Operation Time: Compared to other traditional methods, the operation time is increased by 20 – 30 minutes while performing computer assisted total knee surgery. The increased time depends on the surgeon and how familiar he is with the computers and the amount of experience he has performing the knee surgery. 

The Cost Factor: Cost of the medical procedure is absolutely a factor particularly in nations like India. At present, the cost of computer knee arrangement medical procedure is around 20-25% higher. 

The Surgeon’s Age: Not a lot of older surgeons are familiar with the computer. Compared to younger surgeons, older surgeons are less inclined to utilize this technology. In most of the countries around the world, the orthopaedic surgeons who are in their peak practise are aged around 45 – 50 years. They have graduated in and around the 90’s when computer assistance wasn’t much famous. Hence, they are not much familiar with this methodology. 


What is the future of computer assisted knee replacement surgery?

Despite the fact that computer assisted knee replacement medical procedure isn’t yet standard, it is highly unlikely to escape the technological advancement. With the current concerns of cost, duration of the procedure, the surgeon’s willing to learn the technology, will change eventually with the advancement of the technology. If not today, there will be a tomorrow where computer assisted knee replacement surgery is highly common in most of the hospitals.