Understanding the Use of Robotics in Spine Surgery

In recent years, the use of robotic systems in surgery has increased in popularity, including in spine surgery. Pedicle screw placement is a crucial aspect of spine surgery that can benefit from the use of robotic technology.

However, accuracy is paramount, as screw malposition can result in severe complications. Robotic systems must offer comparable accuracy to established methods of screw placement. Early reports suggest that robotic systems offer equivalent accuracy and reduced radiation exposure.

Over the last ten years, surgical robotics have gained popularity in specialties like general surgery, urology, and gynecology for manipulating tissue in body cavities. The early adoption of robotic systems in these fields has driven innovation and their use in other subspecialties, including spine surgery.

Spinal pathologies often require pedicle screw placement for fixation, which has evolved with navigated techniques since the late 1950s. Robotics is now an area of opportunity for accurate pedicle screw placement in spine surgery, reducing potential complications and improving outcomes.

Efficient and accurate screw placement is crucial for robotic systems to be widely adopted in spine surgery. Robotic technologies can automate repetitive tasks and reduce human error, with early reports showing similar accuracy to established methods. Several FDA-approved robotic systems, including

ExcelsiusGPS, Mazor X Stealth Edition, and ROSA ONE Spine, are commercially available. However, direct comparison between these systems is difficult due to the cost and time associated with adoption.

Operative Technique

Robotic systems can be used for spinal fusion procedures that require pedicle screw fixation. The integration of robotics has mainly been observed in lumbar fusion surgeries, which include anterior lumbar interbody fusion, lateral lumbar interbody fusion, and transforaminal lumbar interbody fusion.

Percutaneous technique has been the prevalent method for pedicle screw fixation, although open screw placement has also been conducted. Moreover, depending on the surgery being performed, patients may be positioned in either the prone or lateral stance.

• The patient is made ready and covered using established sterile techniques.
• At first, two minor cuts are created on both sides over the posterior superior iliac spine.
• The dynamic reference base array and surveillance marker are then placed onto the posterior superior iliac spine bilaterally in a superolateral direction.
• The intraoperative CT registration fixture is connected to the dynamic reference base array.
• An intraoperative CT scan is conducted using O-arm to co-register with the preoperative imaging.
• A trajectory plan may be created for each pedicle screw or pre planned before surgery to reduce intraoperative time.
• The robotic end effector arm is then positioned to direct all subsequent actions along the planned trajectory.

All subsequent steps can be accomplished via the end effector arm.

• To place a pedicle screw, a small incision is made and the skin is dissected using an electrocautery tool. The fascia is also cut, which is important to ensure the screw goes in the right direction.
• A bur is then used to create a pilot hole in the bone, which helps the drill to go in smoothly.
• The trajectory is planned using navigation and the screw is placed using the same system.
• The surgeon is notified when the screw is in the right position, and a force meter confirms that the instruments are being used correctly.
• Finally, a CT scan is performed to ensure the screw is in the right place.

Other Surgical Considerations

Screws are most commonly placed through small incisions in the skin. Nevertheless, in some situations, such as when a spinal decompression is required for degenerative conditions, open screw placement may be necessary.

When an open procedure is performed, instead of positioning the dynamic reference base array and intraoperative CT registration fixture on the posterior superior iliac spine, they are placed on a spinous process above and below the region being operated on.

All future procedures can be carried out as mentioned earlier, with the exception of ensuring that the dynamic reference base array is not disturbed in the surgical area. During an open exposure, the screw entry site can be directly visualized, and it may be necessary to drill away cortical bone to facilitate the screw placement.

The usual application of this method is for patients in the conventional prone position. Nevertheless, there has been growing interest in conducting lumbar fusion surgery with the patient in a single position, which is the lateral position. These involve surgeries such as anterior lumbar interbody fusion and lateral lumbar interbody fusion with pedicle screw fixation, both of which can also incorporate the use of a robotic system.

These techniques involve inserting an interbody either through an incision made in the front or the side of the body, and then using pedicle screws for fixation. If the lateral approach is used, modifications are made to the trajectory of the screws on the lower side to reduce the chance of infection. All other steps remain unchanged.

Accuracy of Pedicle Screw Placement

Our doctors at Complete Orthopedics want to ensure the safety and accuracy of pedicle screw placement during surgery. There are now robotic systems available to aid in this procedure, and research has shown that they can achieve a high level of accuracy, typically between 94% to 98%. Nevertheless, there is conflicting evidence in the literature regarding the precision of robot-assisted screw placement in comparison to conventional freehand methods.

While certain research has found that the accuracy of pedicle screw placement with robotic assistance is subpar, other studies have demonstrated that it is either just as good or even better than freehand methods. Recent meta-analyses support this, revealing that robot-assisted pedicle screw placement is typically more precise than freehand placement.

Navigation with intraoperative CT scan is another commonly used method for pedicle screw fixation. Some surgeons contend that the precision of screw placement with navigation is sufficiently high that a robotic arm is unnecessary. However, literature supports the use of a robotic arm for several reasons.

One reason to support the use of a robotic arm is that preoperative CT scanning permits screw planning prior to the operation, which leads to reduced surgery time and improves the precision of screw placement. Another factor is that the robotic arm can minimize the human error that is often associated with manual tasks. Additionally, employing a robotic arm can be less physically demanding for the surgeon.

Operative Time

Incorporating robotic technology into spine surgery can increase the time it takes to perform the procedure. Studies have shown that this may be due to the steep learning curve associated with using this technology.

Nevertheless, as surgeons become more experienced and technology improves, it is expected that the additional operative time will decrease. Previous studies have shown that after an initial learning period, there is an improvement in accuracy with the use of robotics.

Radiation Exposure

Robotic systems in spine surgery can offer decreased radiation exposure to both the surgeon and patient. The use of a preoperative CT scan and fluoroscopy during surgery to register the robotic system allows for minimal intraoperative radiation. Multiple studies have shown that the overall and per-screw radiation exposure times are lower with the use of robotic systems.

Future Directions

Rapid advancements are being made in the use of robotic systems in spine surgery, but there is a need for further enhancement of efficiency and surgical workflow to encourage broader implementation. Enhancing imaging software is crucial in reducing errors and aiding with trajectory planning both before and during surgery.

By automating repetitive tasks and decreasing human error, robotic systems strive for more uniform patient outcomes. Although existing research primarily concentrates on fixing the thoracolumbar spine, robotics has the potential to be employed in cervical and pelvic fixation in the future, along with more intricate procedures like decompression and complex deformity surgeries.

Assessing various robotic systems against one another may aid in identifying their particular advantages and drawbacks. Cost is another factor to bear in mind, and the feasibility of implementing these systems more broadly will depend on their economic viability.

The utilization of robotic systems in spine surgery has gained popularity, offering advantages such as enhanced precision of screw placement, shorter operation time, and lowered radiation exposure.

Yet, mastering the use of these systems effectively poses challenges, and further technical progress is necessary to boost their efficacy. Adopting a well-rounded approach is crucial in evaluating the implementation of robotic systems versus conventional techniques for screw placement.

If you are interested in knowing more about Robotics in Spine Surgery you have come to the right place!