Computer-assisted surgical techniques allow surgeons to achieve far greater precision when performing certain types of surgery, including joint replacement surgery. The success of joint replacement procedures depends on the accurate and exact placement of the prosthetic components with regard to the patient’s unique anatomy for optimal functioning.
With computer technology providing additional information about the joint during replacement surgery, surgeons are able to achieve higher rates of reproduction, with a reduced risk of complications both during surgery and afterward.
What are the benefits of computer-assisted joint replacement surgery?
The surgeon uses computer-assisted joints replacement for several types of joint replacement surgeries. This includes the two most commonly performed joint replacement surgeries in the U.S. – knee replacement and hip replacement.
Although these surgeries are already associated with high rates of success, when complications do arise, they most often involve misalignment of the joint components or other issues affecting the positioning of the joint that winds up causing uneven or excessive wear and tear on the joint and eventual loosening or slippage.
Today’s artificial joint products are designed to perform with every piece dependent on another for ideal results. Even a tiny degree of error in placing a joint component can result in a very small misalignment. That error can still have major consequences with regard to function and comfort.
The computer-assisted technology uses two- and three-dimensional real-time imaging of the joint. This is just to provide “live” feedback of the procedure for placement of the joint components for superior results.
How to perform computer-assisted joint replacement surgery?
Computer-assisted techniques use a series of special electronic probes attached to the patient in specific locations to enable two- and three-dimensional relational viewing of the joint, the surgical instruments, the implant components and the surrounding tissues. Images transmitted to a monitor for viewing.
The computer probes are highly sensitive, and the information they provide plays a critical role in minimally-invasive joint replacement procedures. Because the probes are continually sensing changes in relational positioning between the natural joint and the prosthetic components and surgical instruments, the surgeon is able to make slight changes intraoperatively to help achieve optimal outcomes based on each patient’s unique anatomy.
Am I a candidate for computer-assisted joint replacement surgery?
Replacement of the knee, hip and other joints is reserved for patients in whom more conservative approaches like medication and physical therapy have failed to provide ongoing, meaningful relief, and in patients for whom those conservative options are not practical or recommended. While computer-assisted surgical techniques can be used in many patients. The technology is not always the ideal choice for every surgery or every patient.
An in-depth evaluation of the joint prior to surgery using diagnostic imaging with or without arthroscopy to see inside the joint can help determine if a computer-assisted approach is recommended. Other factors may also play a role in determining the best approach to surgery. The surgeon shall discuss the pros and cons of computer-assisted techniques during the presurgical consultation appointment.
Although joint replacement technology and surgical techniques have improved significantly during the past decade and an increased use of computer- and robot-assisted surgeries have helped to improve accuracy and decrease complications, the fact is, there is still no substitute for experience and surgical skill. Joint replacement surgery relies heavily on the assessment of the joint both before and during surgery. Proper preparation of the joint and the replacement components and, of course, accurate and highly precise placement of the components in order to achieve the best possible results.
Computer Navigated Total Knee Replacement & Robotic Knee Replacement
With an intent to improve the patient satisfactions course, computer-assisted technology and robotic technology have been introduced into the world of total knee replacements.
Studies have shown that correct positioning of the components will lead to better longevity of the total knee implants. To achieve correct alignment of the knee, precise placement of the components in the total knee replacement is mandatory. The mechanical axis of the lower extremity is also better restored with accurate placement of total knee replacements.
These computer-assisted navigation and robotic technologies are useful not only for a total knee replacement, but also for partial knee replacement surgery.
Computer-assisted total knee technologies can be classified under three types:
- Imageless technologies that include accelerometer-based technologies.
- Preoperative image-based technologies.
- Intraoperatively based technologies.
Imageless technologies can be further classified into two types. Accelerometer based and optical navigation system based technologies. KneeAlign (made by OrthAlign System) is an example of Accelerometer based system. It uses handle accelerometer that attaches to the bone and helps in navigation similar to optical based imageless navigation systems that guide computer navigation of knee replacement surgery.
The image-based computer-assisted technologies use preoperative MRI or CT scan to form a 3D module. Intraoperatively the sensors placed on the bone capture the preoperative images to help in better placement of the components.
Robotic-assisted total knee replacement is extension of the technology and advancement of the technology of computer-assisted navigation.
Currently, we have four robotic systems available:
- Mako system made by Stryker.
- The NAVIO system made by Smith and Nephew.
- iBlock made by OMNIlife.
- Curexo made by Robodoc Company.
The robotic arm guides a surgeon’s hand and this type of robotic assistant is called as a “semiactive” system. The surgeon is the person making the cuts and the surgeon’s hand is guided by the robot.
There are two types of robotic assistants; one is fully active and the other is semiactive. Mako is a semiactive type of robotic system. Robodoc was earlier system in the 1980s that was fully active system. There were increased surgical complications with the fully active systems because of injury to the soft tissues around the hip.
Today, we use the semiactive system which offers active constrain to the cuts and to the reaming done in the bone. The surgeon has good control over the process sand there is auditory as well as tactile feedback given to the surgeon based on a boundary created by the surgeon in the computer based on the preoperative planning.
Using a robot for drilling the bone permits one stage reaming of the bone as against going one size after the other because the surgeon knows exactly the size of the components. Surgical time still may be increased, especially in the initial part of the learning curve of the surgeon. Additional time is required for robotic assisted surgical procedures especially with registration of the bone that is needed for the robot to pick up the architecture of the bone.
Robotic systems in addition require upfront financial cost for the robot and also for software increments that happen over time. The potential technical complications could include motin at the bone – pin interface during the registration process. The pins may move and may change the alignment of the components if the surgeon is not careful. The surgeon also has to ensre that registration is accurate to avoid errors in component placement. Milling and broaching defects may occur if the robot is not used correctly.
Literature is clear in stating that computer-assisted navigation is associated with significantly operative times than conventional surgery. This literature has also shown that there is a higher chance of optimal component placement using computer-navigated assistance and if the components are correctly aligned. The risk of requiring revision surgery in the long term is hopefully decreased.
The risks and benefits have to be balanced by the surgeon in choosing a technique for computer-assisted surgery.
Apart from the benefit of helping with improving alignment, computer-assisted surgery has the advantage of being less invasive because with computer-assisted surgery, the femoral canal does not need to be drilled for placement of the jigs. This can decrease the blood loss intraoperatively and in the postoperative period. Navigation does improve the coronal plane alignment, but certain navigation systems do not allow better placement in the other planes.
Computer-assisted surgery does have downsides and limitations. There is additional surgical cost associated with computer-assisted navigation. There are also certain issues, which are very specific for computer-assisted technologies including some additional complications that can happen very specifically for computer-assisted technologies.
The surgeon has to be careful in what input is given to the computer. If the surgeon gives incorrect feedback to the computer, the computer is going to guide the surgeon to provide incorrect placement of the prosthesis, which can significantly damage the mechanical alignment of the limb leading to a need for revision. As I always say “garbage in and garbage out!”
Additionally if pins are needed to be placed into the bone, the pins cause stress fractures after removal and can lead to fracture. There is also a risk of infection of these pin sites. Additional surgical work increases the time for this procedure and additional operative time can lead to increase risk of complications like increased anesthesia, increased risk of infection, etc.
To conclude, I use computer-assisted surgery only for total knee replacements around extra articular deformities. I feel it’s a useful tool to improve the accuracy of component positioning and improve the limb alignment. It does decrease radiographic outliers. Reduction in blood loss is another advantage that will improving patient reported outcomes.
Computer Assisted Joint Replacement Case Studies
- Coming Soon
Why choose Dr. Kakare?
As a top joint replacement specialist in New York City, Dr. Karkare has a stellar reputation, extensive experience, ensuring patients have the broadest array of safe and effective treatment options to relieve pain and other symptoms.
Dr. Karkare does a thorough examination of each patient to gauge if an anterior method would be a good choice before any procedure is performed.
This enables every patient to make an informed, educated decision so they can feel confident in their care every step of the way.
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