Three-Dimensional Navigation in Lumbar Spine to Facilitate Minimally Invasive Spine Surgery

46 Three-Dimensional Navigation in Lumbar Spine to Facilitate Minimally Invasive Spine Surgery

Jang W. Yoon, Gaetano De Biase, and Eric W. Nottmeier

Summary

Three-dimensional navigation has increased both the eﬃciency of the spine surgeon and the accuracy and precision of spinal instrumentation. It is important to have adequate planning prior to starting image-guided lumbar spinal surgery. Navigation can be used in minimally invasive lumbar spinal surgery to accurately localize the underlying anatomy, thereby facilitating accurate skin incision and a safe trajectory to the underlying pathology. Although three-dimensional image-guided navigation oﬀers the surgeon an excellent tool for accurate identification of the anatomy, this should only be used as an adjunct and should not replace a thorough knowledge of the spinal anatomy. The robotic spine procedure has still not hit its prime time due to various reasons including added complexity of the case, longer operative time versus the standard techniques, high cost of installation, and so on.

Keywords: image guidance lumbar fusion three-dimensional navigation MIS robotics augmented reality

46.1 Introduction

The utilization of three-dimensional image guidance in spine surgery was first introduced in the mid-1990s.1 In an effort to improve the accuracy and precision of spinal instrumentation such as pedicle screw placement, this technology has evolved from the traditional open fixation to two-dimensional fluoroscopy guidance with Kirschner wire (K-wire) placement and now to three-dimensional image guidance without the use of K-wires. This has increased both the efficiency of the spine surgeon and the safety of spinal instrumentation, all of which serve tremendous benefits for patients undergoing spine surgery. Nottmeier et al were able to demonstrate in a retrospective review of 220 consecutive patients undergoing posterior spinal fusion using three-dimensional image guidance, a low complication rate and high accuracy of instrumentation despite a high percentage of revision cases.² As a result of the introduction of three-dimensional image guidance, Tehli et al have demonstrated a 98% accuracy in pedicle screws placement using neuronavigation and intraoperative image guidance in spinal stabilization surgery.³ An added advantage of three-dimensional image-guided navigation in minimally invasive spine surgery (MISS) is the complete elimination of radiation exposure to the surgeon and operating room (OR) staff, unlike the two-dimensional intraoperative fluoroscopy guidance with significant radiation exposure.⁴

Minimally invasive lumbar spine surgery continues to gain popularity among patients due to its shorter recovery time, better cosmetics, and an overall decreased morbidity.⁵ Employing three-dimensional image guidance in minimally invasive lumbar spine surgery can help facilitate percutaneous instrumentation without the use of fluoroscopy or K-wires and can also enable the surgeon to register multiple vertebral segments at a time. This makes three-dimensional image-guided minimally invasive lumbar spine surgery a very attractive option for both the spine surgeon and for the patients. In this chapter, we review three-dimensional navigation in the lumbar spine and how it facilitates MISS.

46.2 Preoperative Planning

It is important to have adequate planning prior to starting image-guided lumbar spinal surgery. Spinal image guidance can be accomplished by point-matching registration using a preoperative computed tomography (CT) scan or images can be acquired intraoperatively. Other preoperative factors include adequate patient selection, positioning, neuromonitoring, and the right surgical tools needed for the specific surgery. Surgeon’s competency and experience in image-guided minimally invasive lumbar spine surgeries is also paramount to the success of the operation.

46.3 Patient Selection: Indications and Contraindications

Navigation can be used in minimally invasive lumbar spinal surgery to accurately localize the underlying anatomy, thereby facilitating accurate skin incision and a safe trajectory to the underlying pathology. This is useful because it gives the surgeon an added layer of assurance especially when dealing with complex patients and distorted anatomy due to prior surgeries. Also, this technology can be applied to different minimally invasive approaches to the lumbar spine and for different conditions, including spinal deformity, degenerative disc disease, traumatic fractures, malignancy, and adjacent segment disease from previous spinal fusions.

There are few contraindications to the use of three-dimensional navigation in minimally invasive lumbar spine surgery; the first being unfamiliarity with this technology and its utilization, and any condition that precludes exposure to radiation like pregnancy.

46.4 Patient Positioning

46.4.1 Surgical Table Selection

Selecting the right table is critical for the success of image-guided lumbar spine surgery. Ideally, the surgical table should allow for easy patient positioning, exposure, and intraoperative imaging. The O-arm should be able to fit around the patient on the table and move up and down without any obstruction from the base of the table. The Jackson table is suitable for this purpose as it is able to conform to the patient’s normal lumbar lordosis while in the prone position.

46.4.2 Sterile Draping

To avoid contamination of the surgical field, the entire O-arm has to be properly draped which can be a cumbersome task. Also, if not properly done, the drape can become lose and get caught during movement, which can cause delays and frustrations during surgery. The preferred method of draping the patient in our practice is to cover the patient in a 360-degree circumferential manner with sterile drapes (Fig. 46.1). It is also important to make sure the reference arc is not covered by the drape as it has to be visible to the camera on the navigation system.

Fig. 46.1 For sterile draping technique, antibiotic irrigation solution is used to fill the surigcal cavity and split-sheet drapes is circumferentially enclosed sterily while keeping the reference arc just above the drapes. The position of the navigation camera is adjusted to ensure that the navigation arc is in line while the intraoperative cone beam computed tomography (CT) scan is obtained.

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