Isocentric Navigation for the Training of Percutaneous Endoscopic Transforaminal Discectomy: A Feasibility Study

Applications of navigation in full-endoscopic spine surgery

PURPOSE

Advancement in all surgery continues to progress towards more minimally invasive surgical (MIS) approaches. One of the platform technologies which has helped drive this trend within spine surgery is the development of endoscopy; however, the limited anatomic view experienced when performing endoscopic spine surgery requires a significant learning curve. The use of intraoperative navigation has been adapted for endoscopic spine surgery, as this provides computer-reconstructed visual data presented in three dimensions, which can increase feasibility of this technique to more surgeons.

METHODS

This paper will describe the principles, technical considerations, and applications of stereotactic navigation-guided endoscopic spine surgery.

RESULTS

Full-endoscopic spine surgery has advanced in recent years such that it can be utilized in both decompressive and fusion surgeries. One of the major pitfalls to any minimally invasive surgery (including endoscopic) is that the limited surgical view can often complicate the surgery or confuse the surgeon, leading to longer operative times, higher risks, among others. This is the real utility to using navigation in conjunction with the endoscope-when registered correctly and utilized appropriately, navigated endoscopic spine surgery can take some of the guesswork out of the minimally invasive approach.

CONCLUSIONS

Using navigation with endoscopy in spine surgery can potentially expand this technique to surgeons who have yet to master endoscopy as the assistance provided by the navigation can alleviate some of the complexities with anatomic understanding and surgical planning.

Indirect Puncture Using a Novel Arc Puncture-Guided Device in Percutaneous Transforaminal Puncture on Goat Lumbar Spine Specimens

OBJECTIVE

We investigated the indirect puncture method using a novel arc puncture-guided device in percutaneous transforaminal puncture to improve puncture accuracy and reduce the fluoroscopy, puncture, and operation times.

METHODS

We have designed a novel arc puncture-guided device consisting of a 90° arc block and a 30° arc block. Punctures were performed on 8 fresh goat lumbar spine specimens. A senior doctor performed indirect punctures on the left side of the L2-L3, L3-L4, and L4-L5 levels using the novel device (group A) and on the right side of the L2-L3, L3-L4, and L4-L5 levels using the conventional method (group B). We recorded the fluoroscopy, puncture, and operation times.

RESULTS

In group A, the first puncture could successfully reach the target after 1-3 punctures, and the one-time success rate of the second needle puncture was 91.67%. The total fluoroscopy time was 14.88 ± 0.99 minutes in group A and 16.08 ± 2.22 minutes in group B (P = 0.027). The puncture times were 3.00 ± 0.66 minutes in group A and 6.04 ± 2.13 minutes in group B (P < 0.01). The operation time was 273.75 ± 30.19 minutes in group A and 361.25 ± 69.57 minutes in group B (P < 0.01). The differences in fluoroscopy times, puncture times, and operation times between the 2 groups were statistically significantly (P < 0.05).

CONCLUSIONS

Indirect puncture using the novel arc puncture-guided device for percutaneous transforaminal puncture can significantly improve puncture accuracy and reduce the fluoroscopy, puncture, and operation times. Indirect puncture using the novel device in percutaneous transforaminal endoscopic discectomy is a potential and practical puncture method.

Application of Mixed Reality Using Optical See-Through Head-Mounted Displays in Transforaminal Percutaneous Endoscopic Lumbar Discectomy

Purpose

Mixed reality (MixR) technology merges the real and virtual worlds to produce new environments and visualizations; it is being tested for numerous minimally invasive surgical procedures. This study is aimed at evaluating the use of MixR technology using optical see-through head-mounted displays (OST-HMDs) during transforaminal percutaneous endoscopic discectomy (TPED).

Methods

Forty-four patients treated with MixR-assisted TPED through OST-HMDs were compared with matched patients treated with conventional TPED (n = 43). In the MixR-assisted TPED group, MixR technology was used to navigate the four procedures of marking, needle insertion, foraminoplasty, and positioning of the working sheath. The clinical outcomes were evaluated based on the numerical rating scale (NRS) scores and Oswestry Disability Index (ODI) on preoperative and postoperative day 1 and at the last follow-up examination. The procedural times, radiation exposure, and eye fatigue were also recorded. All patients were followed up for at least 6 months.

Results

The NRS scores and ODI were significantly improved in both groups at the last follow-up visit compared with the preoperative values (P < 0.05); these values were not statistically different between the groups. The operation time and radiation exposure during marking, needle insertion, and total procedure significantly decreased in the MixR-assisted TPED group compared to those in the conventional TPED group (P < 0.05). Unfortunately, the incidence of eye fatigue increased owing to the use of OST-HMDs in the MixR-assisted TPED group.

Conclusion

This study shows the utility of MixR technology for image guidance in conventional TPED. Radiation exposure is decreased, and this technology serves as a valuable tool during the TPED procedure; however, the assistance of conventional fluoroscopy is still required.

Does Robot Navigation and Intraoperative Computed Tomography Guidance Help with Percutaneous Endoscopic Lumbar Discectomy? A Match-Paired Study

OBJECTIVE

To evaluate the efficacy and safety of robot-assisted percutaneous endoscopic lumbar discectomy (rPELD) using a specially designed orthopaedic robot with an intraoperative computed tomography-equipped suite for treatment of symptomatic lumbar disc herniation and compare rPELD with fluoroscopy-assisted percutaneous endoscopic lumbar discectomy (fPELD).

METHODS

We retrospectively reviewed and compared demographic data, radiologic workups, and patient-reported outcomes of 39 patients treated with rPELD and 78 patients treated with fPELD at our institution between January 2019 and December 2019.

RESULTS

Our data showed that a single-shot puncture in the rPELD group was significantly more precise compared with 4.12 ± 1.71 trials in the fPELD group (P < 0.001). There was an overall reduction of fluoroscopy (21.33 ± 3.89 times vs. 33.06 ± 2.92 times, P < 0.001), puncture-channel time (13.34 ± 3.03 minutes vs. 15.03 ± 4.5 minutes, P = 0.038), and total operative time (57.46 ± 7.49 minutes vs. 69.40 ± 12.59 minutes, P < 0.001) using the rPELD technique versus the fPELD technique. However, there were no significant differences in patient-reported outcomes, length of hospital stay, and complication rate between the 2 groups (P > 0.05).

CONCLUSIONS

Taken together, our data indicate that rPELD provides a precise skin entry point and optimal trajectory for puncture, which increases the success rate of PELD, negating the need for revision surgery. However, further studies are required to confirm the superiority and application of the rPELD technique.

Mixed Reality-Based Preoperative Planning for Training of Percutaneous Transforaminal Endoscopic Discectomy: A Feasibility Study

OBJECTIVE

To explore the effect of preoperative planning using mixed reality (MR) on training of percutaneous transforaminal endoscopic discectomy (PTED).

METHODS

Before the training, we invited an experienced chief physician to plan the puncture path of PTED on the X-ray films of the lumbar spine model and the 3D Slicer platform, respectively, and used this as the standard to guide trainees. In the aggregate, 60 young residents were randomly divided into Group A (N = 30) and Group B (N = 30). Group A learned the 2-dimensional standard planning route, whereas Group B learned the standard route planning based on MR through the 3D Slicer platform. Then, trainees were asked to conduct PTED puncture on a lumbar spine model. Questionnaires were distributed to trainees before and after the training. During the training, puncture times, operating time (minutes), and fluoroscopy times were recorded.

RESULTS

After the training, it was obvious that more trainees showed their recognition of MR, believing that MR could help preoperative planning and training of PTED. Their high satisfaction with the training indicated the success of our training. Moreover, puncture times, operating time (minutes), and fluoroscopy times of Group B were significantly lower than those of Group A.

CONCLUSIONS

MR technology contributes to preoperative planning of PTED and is beneficial in the training of PTED. It significantly reduces puncture times and fluoroscopy times, providing a standardized method for the training of PTED.

Preoperative Design for the Posterolateral Approach in Full-Endoscopic Spine Surgery for the Treatment of L5/S1 Lumbar Disc Herniation

OBJECTIVE

Full-endoscopic spine surgery (FESS) is a relatively less invasive treatment for lumbar disc herniation (LDH). This study investigated the optimal operative route of the posterolateral approach (PLA) of FESS for the treatment of L5/S1 LDH.

METHODS

Between June 2016 and November 2018, a total of 21 patients with leg pain due to L5/S1 LDH underwent PLA of FESS. According to the partial removal of the superior articular process (SAP) of the L5/S1 facet joint (FJ), we categorized these patients into 2 groups. LDH type, anatomical configurations (FJ, sacral ala [SA], and iliac crest [IC]), the presence or absence of spondylolysis, operation time, and operative outcome were compared between these 2 groups.

RESULTS

Although the anatomical configuration of the FJ was the most important factor for the necessity of SAP removal, the configuration of the SA and IC did not restrict endoscope insertion and subsequent LDH removal. Even in intracanal LDH, the removal of SAP was not absolutely required depending on the FJ configuration. Furthermore, the presence of spondylolysis was a factor associated with the unnecessity of SAP removal.

CONCLUSION

Detailed radiological examination of the FJ configuration is an important preoperative investigation to determine the optimal operative route for PLA of FESS.