Augmented Reality-Assisted Spine Surgery: An Early Experience Demonstrating Safety and Accuracy with 218 Screws

Study Design Prospective cohort study. Objectives In spine surgery, accurate screw guidance is critical to achieving satisfactory fixation. Augmented reality (AR) is a novel technology to assist in screw placement and has shown promising results in early studies. This study aims to provide our early experience evaluating safety and efficacy with an Food and Drug Administration-approved head-mounted (head-mounted device augmented reality (HMD-AR)) device. Methods Consecutive adult patients undergoing AR-assisted thoracolumbar fusion between October 2020 and August 2021 with 2 -week follow-up were included. Preoperative, intraoperative, and postoperative data were collected to include demographics, complications, revision surgeries, and AR performance. Intraoperative 3D imaging was used to assess screw accuracy using the Gertzbein-Robbins (G-R) grading scale. Results Thirty-two patients (40.6% male) were included with a total of 222 screws executed using HMD-AR. Intraoperatively, 4 (1.8%) were deemed misplaced and revised using AR or freehand. The remaining 218 (98.2%) screws were placed accurately. There were no intraoperative adverse events or complications, and AR was not abandoned in any case. Of the 208 AR-placed screws with 3D imaging confirmation, 97.1% were considered clinically accurate (91.8% Grade A, 5.3% Grade B). There were no early postoperative surgical complications or revision surgeries during the 2 -week follow-up. Conclusions This early experience study reports an overall G-R accuracy of 97.1% across 218 AR-guided screws with no intra or early postoperative complications. This shows that HMD-AR-assisted spine surgery is a safe and accurate tool for pedicle, cortical, and pelvic fixation. Larger studies are needed to continue to support this compelling evolution in spine surgery.

Intraoperative 3D imaging with cone-beam computed tomography leads to revision of pedicle screws in dorsal instrumentation: a retrospective analysis

Background Correct positioning of pedicle screws can be challenging. Intraoperative imaging may be helpful. The purpose of this study was to evaluate the use of intraoperative 3D imaging with a cone-beam CT. The hypotheses were that intraoperative 3D imaging (1) will lead to an intraoperative revision of pedicle screws and (2) may diminish the rate of perforated screws on postoperative imaging. Methods Totally, 351 patients (age 60.9 ± 20.3 a (15–96); m/f 203/148) underwent dorsal instrumentation with intraoperative 3D imaging with 2215 pedicle screws at a trauma center level one. This study first evaluates intraoperative imaging. After this, 501 screws in 73 patients (age 62.5 ± 19.7 a; m/f 47/26) of this collective were included in the study group (SG) and their postoperative computed tomography was evaluated with regard to screw position. Then, 500 screws in 82 patients (age 64.8 ± 14.4 a; m/f 51/31) as control group (CG), who received the screws with conventional 2D fluoroscopy but without 3D imaging, were evaluated with regard to screw position. Results During the placement of the 2215 pedicle screws, 158 (7.0%) intraoperative revisions occurred as a result of 3D imaging. Postoperative computed tomography of the SG showed 445 (88.8%) screws without relevant perforation (type A + B), of which 410 (81.8%) could be classified as type A and 35 (7.0%) could be classified as type B. Fifty-six (11.2%) screws in SG showed relevant perforation (type C–E). In contrast, 384 (76.8%) screws in the CG were without relevant perforation (type A + B), of which 282 (56.4%) could be classified as type A and 102 (20.4%) as type B. One hundred and sixteen (23.2%) screws in the CG showed relevant perforation (type C–E). Conclusion This study shows that correct placement of pedicle screws in spine surgery with conventional 2D fluoroscopy is challenging. Misplacement of screws cannot always be prevented. Intraoperative 3D imaging with a CBCT can be helpful to detect and revise misplaced pedicle screws intraoperatively. The use of intraoperative 3D imaging will probably minimize the number of revision procedures due to perforating pedicle screws.

Intraoperative 3D Imaging with Cone-Beam Computed Tomography Leads to Revision of Pedicle Screws in Dorsal Instrumentation – A Retrospective Analysis.

Background: Correct positioning of pedicle screws can be challenging. Intraoperative imaging may be helpful. The purpose of this study was to evaluate the use of intraoperative 3D imaging with a cone-beam CT. The hypotheses were that intraoperative 3D imaging (1) will lead to an intraoperative revision of pedicle screws and (2) may diminish the rate of perforated screws on postoperative imaging.Methods: 351 patients (age 60.9 ± 20.3 a (15-96); m/f 203/148) underwent dorsal instrumentation with intraoperative 3D imaging with 2215 pedicle screws at a trauma center level one. This study first evaluates the intraoperative imaging. After this, 501 screws in 73 patients (age 62.5 ± 19.7 a; m/f 47/26) of this collective were included in the study group (SG) and their postoperative computed tomography was evaluated with regard to screw position. Then 500 screws in 82 patients (age 64.8 ± 14.4 a; m/f 51/31) as control group (CG), who received the screws with conventional 2D fluoroscopy but without 3D imaging, were evaluated with regard to screw position. Results: During the placement of the 2215 pedicle screws 158 (7.0%) intraoperative revisions occurred as a result of 3D imaging. Postoperative computed tomography of the SG showed 445 (88.8%) screws without relevant perforation (type A+B), of which 410 (81.8%) could be classified as type A and 35 (7.0%) could be classified as type B. 56 (11.2%) screws in SG showed relevant perforation (type C-E). In contrast, 384 (76.8%) screws in the CG were without relevant perforation (type A+B), of which 282 (56.4%) could be classified as type A and 102 (20.4%) as type B. 116 (23.2%) screws in the CG showed relevant perforation (type C-E).Conclusion: This study shows that correct placement of pedicle screws in spine surgery with conventional 2D fluoroscopy is challenging. Misplacement of screws cannot always be prevented. Intraoperative 3D imaging with a CBCT can be helpful to detect and revise misplaced pedicle screws intraoperatively. The use of intraoperative 3D imaging will probably minimize the number of revision procedures due to perforating pedicle screws.

Does the use of intraoperative CT scan improve outcomes in Orthopaedic surgery? A protocol for systematic review and meta-analysis

BackgroundIntraoperative 3D imaging is a valuable tool to visualise complex anatomical structures and position implants optimally. This is an emerging technology and there is a paucity in literature of articles describing the same.ObjectivesThis systematic review aims to compare the outcome of surgeries done under 3D imaging to those done under 2D fluoroscopy by analysing the evidence in literature.MethodsA systematic review will be conducted adhering to the PRISMA guidelines. Electronic databases of PubMed, Embase and Scopus will be searched with a pre-defined search string. A manual search will also be conducted on the references of the included articles. Original research articles published in English that directly compare the outcomes of intraoperative 3D imaging with fluoroscopy will be included. Review articles, conference abstracts and animal studies will be excluded. Outcome measures will be extracted from the selected studies and analysed with the help of appropriate software.

Biomechanics and clinical outcome after posterior stabilization of mid-thoracic vertebral body fractures: a systematic literature review

Purpose The aim of this review is to systematically screen the literature for clinical and biomechanical studies dealing with posterior stabilization of acute traumatic mid-thoracic vertebral fractures in patients with normal bone quality. Methods This review is based on articles retrieved by a systematic search in the PubMed and Web of Science database for publications up to December 2018 dealing with the posterior stabilization of fractures of the mid-thoracic spine. Results Altogether, 1012 articles were retrieved from the literature search. A total of 960 articles were excluded. A total of 16 articles were dealing with the timing of surgery in polytraumatized patients, patients suffering of neurologic deficits after midthoracic fractures, and the impact of concomitant thoracic injuries and were excluded. Thus, 36 remaining original articles were included in this systematic review depicting the topics biomechanics, screw insertion, and outcome after posterior stabilization. The overall level of evidence of the vast majority of studies is low. Conclusion High quality studies are lacking. Long-segmental stabilization is indicated in unstable midthoracic fractures with concomitant sternal fractures. Generally, long-segmental constructs seem to be the safer treatment strategy considering the relative high penetration rate of pedicle screws in this region. Thereby, navigated insertion techniques and intraoperative 3D-imaging help to improve pedicle screw placement accuracy.

3D-Imaging navigation in posterior pelvic iliosacral screwing using the Surgivisio® system.

The recent studies about iliosacral screws performed with navigation systems show promising results. The Surgivisio system is a new generation of intraoperative 3D imaging technique used in our institution since two years. The aim of this prospective study was to evaluate the accuracy of iliosacral screw placement and radiation exposure with the Surgivisio® system.Between January 2018 and December 2019, every patient operated for percutaneous iliosacral screwing using the Surgivisio® system were included in this prospective single center study. Accuracy of screw placement was assessed with post-operative high- resolution CT-scan. Operative time, radiation exposure and complications were assessed.A total of 32 patients were included with 49 iliosacral screws. Using the modified Gras classification, 2% (1/49) were rated as misplaced and 2% (1/49) were repositioned. The mean operative time was 26 min for the whole procedure. The mean dose area product was 7.98 Gy.cm2. Two complications were recorded (neurological pain treated by removal of the misplaced screw, an asymptomatic cement leakage with one augmented iliosacral screw).The Surgivisio® system is an efficient navigation tool for iliosacral screwing in minimal invasive surgery. It improves the accuracy of screw placement with an acceptable radiation exposure and operative time.