Robotic versus fluoroscopy-guided pedicle screw insertion for metastatic spinal disease: a matched-cohort comparison

Characterizing the complication profile of spinal robotic systems: A MAUDE analysis of device failures and associated complications by device manufacturer and brand name

INTRODUCTION

Pedicle screw placement in spinal surgery has evolved to incorporate increased use of technology for both preoperative planning and intraoperative guidance. In recent years, robotic guidance has been used to increase the precision, accuracy, and overall patient safety of spinal column fixation via screw placement. Within this context, the present study aims to quantify and classify complications of spinal robotic devices using a nationally representative database.

METHODS

The Manufacturer and User Facility Device Experience (MAUDE) was queried for adverse events involving the most widely used spinal robotic devices from inception to November 3rd, 2023. Entries were tabulated by assigning categorical variables based on event information.

RESULTS

The query yielded 339 unique robotic failure events. The most frequent complications in robotic-assisted spinal surgeries were imprecision (73.6%), software errors (13.7%), and damaged or missing screws (4.9%). Most reported events occurred intraoperatively after the initial incision (78.5%) [compared to preoperatively or postoperatively]. The Mazor X™ system was the most represented spinal robotic platform in terms of complications, accounting for 71.6% of reported robotic failure events. Most reported errors were resolved intraoperatively or continued through the employment of alternative imaging methods and, overall, had minimal clinical significance. With respect to robot-assisted pedicle screw placement, medial breaches were 1.7x more common than lateral breaches across all robotic systems. Finally, regarding the impact of device failures on perioperative timing, we found that 10.3% of adverse events resulted in delays greater than 1 h.

CONCLUSION

Ultimately, imprecision and unresponsive software were found to be two of the most frequent complications of robot-assisted spine surgery. Though most reported errors were circumvented intraoperatively through conventional, non-robotic imaging/guidance methods, 10.3% of adverse events resulted in procedural delays of greater than 1 h.

Complications Have Not Improved With Newer Generation Robots

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

The purpose of this study was to see whether upgrades in newer generation robots improve safety and clinical outcomes following spine surgery.

METHODS

All patients undergoing robotic-assisted spine surgery with the Mazor X Stealth EditionTM (Medtronic, Minneapolis, MN) from 2019 to 2022 at a combined orthopedic and neurosurgical spine service were retrospectively reviewed. Robot related complications were recorded.

RESULTS

264 consecutive patients (54.1% female; age at time of surgery 63.5 ± 15.3 years) operated on by 14 surgeons were analyzed. The average number of instrumented levels with robotics was 4.2 ± 2.7, while the average number of instrumented screws with robotics was 8.3 ± 5.3. There was a nearly 50/50 split between an open and minimally invasive approach. Six patients (2.2%) had robot related complications. Three patients had temporary nerve root injuries from misplaced screws that required reoperation, one patient had a permanent motor deficit from the tap damaging the L1 and L2 nerve roots, one patient had a durotomy from a misplaced screw that required laminectomy and intra-operative repair, and one patient had a temporary sensory L5 nerve root injury from a drill. Half of these complications (3/6) were due to a reference frame error. In total, four patients (1.5%) required reoperation to fix 10 misplaced screws.

CONCLUSION

Despite newer generation robots, robot related complications are not decreasing. As half the robot related complications result from reference frame errors, this is an opportunity for improvement.

A New Pilot Hole Preparation System for Percutaneous Pedicle Screw Placement: A Randomized Controlled Study

STUDY DESIGN

A randomized controlled study.

OBJECTIVE

To introduce a new pilot hole preparation system for percutaneous pedicle screw placement and investigate its efficiency and safety in comparison with the conventional method.

SUMMARY OF BACKGROUND DATA

Placing screws accurately, rapidly, and safely with less radiation exposure is critical for minimally invasive lumbar interbody fusion (LIF). Optimizing pilot hole preparation instruments has important clinical implications.

MATERIALS AND METHODS

A total of 60 patients (180 screws) were included in this study. All patients were randomized into two groups (new system vs. conventional method) and performed single-level minimally invasive percutaneous fixation, interbody fusion, and unilateral decompression. Basic information, time of pilot hole preparation, time of screw placement, and fluoroscopy time were recorded. Screw placement accuracy was graded based on the Gertzbein-Robbins scale, and the angle between the screw axis and the pedicle axis was collected in postoperative CT.

RESULTS

There was no statistical difference in basic information between the 2 groups. The mean time of single pilot hole preparation was 4.08±1.01 minutes in the new system group and 5.34±1.30 minutes in the conventional method group ( P <0.001). The time of single screw placement was significantly shorter in the new system group (0.82±0.20 vs. 1.72±0.33 min), and the fluoroscopy time was also less in the new system group (13.70±3.42 vs. 19.95±5.50 s) ( P <0.001). Screw placement accuracy assessment showed that there were 85 (94.45%) A-grade screws in the new system group while 76 (84.44%) A-grade screws in the conventional method group ( P =0.027).

CONCLUSIONS

The new pilot hole preparation system has shown significant reductions in the time of pilot hole preparation, time of screw placement, and radiation exposure, and has good clinical application value.

Robot-Assisted Spine Surgery: The Pearls and Pitfalls

Robot-assisted spine surgery has gained notable popularity among surgeons because of recent advancements in technology. These innovations provide several key benefits, including high screw accuracy rates, reduced radiation exposure, customized preoperative and intraoperative planning options, and improved ergonomics for surgeons. Despite the promising outcomes reported in literature, potential technical challenges remain across various robotic platforms. It is crucial for surgeons to remember that robotic platforms are shared-control systems, requiring the surgeon to maintain primary control throughout the procedure. To ensure patient safety, surgeons should be well versed in common technical pitfalls and strategies to mitigate these limitations.

Current state and future perspectives of spinal navigation and robotics-an AO spine survey

Introduction

The use of robotics in spine surgery has gained popularity. This study aims to assess the current state of robotics and raise awareness of its educational implications.

Research question

What are the current adoption trends and barriers to the implementation of robotic assistance in spine surgery?

Material and methods

An online questionnaire comprising 27 questions was distributed to AO spine members between October 25th and November 13th, 2023, using the SurveyMonkey platform (https://www.surveymonkey.com; SurveyMonkey Inc., San Mateo, CA, USA). Statistical analyses (descriptive statistics, Pearson Chi-Square tests) and generation of all graphs were performed using SPSS Version 29.0.1.0 (IBM SPSS Statistic).

Results

We received 424 responses from AO Spine members (response rate = 9.9 %). The participants were mostly board-certified orthopedic surgeons (46 %, n = 195) and neurosurgeons (32%, n = 136). While 49% (n = 208) of the participants reported occasional or frequent use of navigation assistance, only 18 % (n = 70) indicated the use of robotic assistance for spinal instrumentation. A significant difference based on the country's median income status (p < 0.001) and the respondent's number of annual instrumentation procedures (p < 0.001) has been observed. While 11 % (n = 47) of all surgeons use a spinal robot frequently, 36 % (n = 153) of the participants stated they don't need a robot from a current perspective. Most participants (77%, n = 301) concluded that high acquisition costs are the primary barrier for the implementation of robotics.

Discussion and conclusion

Although the hype for robotics in spine surgery increased recently, robotic systems remain non-standard equipment due to cost constraints and limited usability.

Early postoperative efficacy of a fully automated orthopedic robotic system-assisted percutaneous pedicle screw fixation for isthmic spondylolisthesis

To assess the feasibility of percutaneous pedicle screw fixation assisted by a fully automated orthopedic robotic system for the treatment of isthmic spondylolisthesis and evaluate its early postoperative outcome. Totally 20 patients with isthmic spondylolisthesis who underwent surgical procedure by the same medical group from March 2020 to March 2023 were retrospectively analyzed, including 10 patients in the robot-assisted group (RA group) and the other 10 patients in the conventional free-hand technique group (FH group). Accuracy of screw insertion was determined using the Gertzbein-Robbins Scale. The accuracy of the novel robotic system was evaluated by comparing the screw position in the preoperative planning and measuring the entry point deviation distance and the trajectory rotation. The differences in operative time, intraoperative blood loss, radiographic fluoroscopy time and fluoroscopic dosage, and length of hospital stay were compared between the two groups. The lumbar visual analog scale scores before and 7 days after operation were analyzed to evaluate the improvement of low back pain as the early postoperative outcome. A total of 84 pedicle screws were placed. In the RA group, 97.5% of screws were Grade A, and 2.5% were Grade B. In the FH group, 88.6% of screws were Grade A, 9.1% were Grade B, and 2.3% were Grade C. No statistical difference was found in the operation time between two groups. The RA group showed a significant reduction in intraoperative blood loss, radiographic fluoroscopy time and fluoroscopic dosage, and length of hospital stay compared to the FH group. The low back pain in both groups was significantly improved after the operation. The novel orthopedic robotic system-assisted percutaneous pedicle screw fixation, with accurate intraoperative screw placement, less surgical damage, less fluoroscopy and shorter length of hospital stay, can be safe and effective for the surgical treatment of isthmic spondylolisthesis.

Effect of pedicle screw misplacement on the pull-out strength using personalized finite element modeling

Intraoperative misplacement of vertebral pedicle screws is prevalent. While a pedicle screw misplacement of up to 4 mm is often considered safe by clinical standards, this may reduce the pull-out strength thereby increasing the risk of postoperative screw loosening. This study aimed to compare the pull-out strength of ideally-placed and misplaced pedicle screws via personalized finite element (FE) modeling simulations. Three-dimensional FE models to simulate pull-out tests of pedicle screws were constructed. Vertebral geometries and material properties were both determined based on computed tomography images from lumbar spine (L1-L5) of a 29-year-old healthy male individual. Pedicle screws were bilaterally placed under four conditions: ideal placement (no cortex perforation) as well as minor medial, minor lateral, and severe lateral misplacements causing cortex perforations. Minor and severe misplacements corresponded to, respectively, grades C and D of the Gertzbein classification. After meshing and voxel-based vertebral material assignments based on two distinct mappings from literature, pull-out strengths were estimated by considering a strain-based damage model to accurately simulate bone fractures. Results indicated that the mean of FE-predicted pull-out forces for ideally-placed screws (1583 and 2412 N for material mappings 1 and 2, respectively) was within the range of previous experimental data (ranging from 1016 to 2443 N) thus confirming the model validation. The mean of all pull-out forces for each misplaced screw group was significantly smaller (p < 0.05) than that of the ideally-placed screws, e.g., 20 % for minor medial, 22 % for minor lateral, and 37 % for severe lateral misplacements. These findings indicated that even clinically-acceptable screw misplacements (up to 4 mm) could significantly reduce the pull-out strengths of pedicle screws thus imposing higher risk of postoperative screw loosening. To avoid these common screw misplacements, the use of advanced approaches for pedicle screw placements appears to be imperative.

Spinal Robotics in Single-Position Lateral Surgery: A Narrative Review of Key Concepts and Considerations

Anterior column realignment via anterior, oblique, or lateral lumbar interbody fusion is increasingly recognized as a powerful mechanism for indirect decompression and sagittal realignment in flexible deformity. Single-position lateral surgery is a popular variation that places patients in the lateral decubitus position, allowing concomitant placement of lateral interbodies and posterior segmental instrumentation without the need for repositioning the patient. The addition of robotics to this technique can help to overcome ergonomic limitations of the placement of pedicle screws in the lateral decubitus position; however, its description in the literature is relatively lacking. In this review we aim to discuss the indications, advantages, and pitfalls of this approach.

Robotic assisted surgery for the treatment of spinal metastases: A case series

OBJECTIVE

Spinal metastases can significantly affect quality of life in patients with cancer and present complex neurosurgical challenges for surgeons. Surgery with instrumentation is often indicated to alleviate pain, preserve neurological function, and ensure mechanical stability. However, distortions in the bony anatomy due to oncological disease can decrease the accuracy of pedicle screw placement. Robotic-assisted surgery may offer an opportunity to increase screw accuracy and improve navigation of spinal lesions compared to conventional techniques. Therefore, we presented our institutional experience evaluating robotic-assisted surgical fixation for spinal metastases.

METHODS

Patients undergoing robotic-assisted surgery at a large tertiary care center between January 2019 - January 2023 for the treatment of spinal metastases were identified. Patient characteristics, including demographics, tumor pathology, surgical complications, and post-operative outcomes were extracted. The Gertzbein Robbins classification system (GRS) was used to assess pedicle screw placement accuracy in patients with post-operative computed tomography.

RESULTS

Twenty patients were identified, including 7 females (35 %), with an overall median age of 66 years (range: 39-80 years) and median BMI of 25 kg/m2 (range: 17-34 kg/m2). An average of four spinal levels were instrumented, with metastases located primarily in the thoracic (n=17, 85 %) spine. Common primary tumor types included prostate (n=4), lung (n=2), and plasma cell (n=2) cancers. Most pedicle screws (92 %) were classified as GRS A in patients with postoperative imaging. Post-operative complications were unrelated to the use of the robot, and included pulmonary embolism (n=1), deep vein thrombosis (n=2), and gastric symptoms (n=3). Three patients were readmitted at 30 days, with one reoperation due to tumor recurrence. Four patients were deceased within 6 months of surgery.

CONCLUSIONS

Despite the inherent high-risk nature of these surgeries, this study underscores the safety and efficacy of robotic-assisted surgery in the management of spinal metastases. Robots can be helpful in ensuring accuracy of pedicle screw placement in patients with metastatic disease.

Advancing robot-guided techniques in lumbar spine surgery: a systematic review and meta-analysis

BACKGROUND

Lumbar spine surgery is a crucial intervention for addressing spinal injuries or conditions affecting the spine, often involving lumbar fusion through pedicle screw (PS) insertion. The precision of PS placement is pivotal in orthopedic surgery. This systematic review compares the accuracy of robot-guided (RG) surgery with free-hand fluoroscopy-guided (FFG), free-hand without fluoroscopy-guided (FHG), and computed tomography image-guided (CTG) techniques for PS insertion.

METHODS

A systematic search of various databases from 1 January 2013 to 30 December 2023 was conducted following PRISMA guidelines. Primary outcomes, including PS insertion accuracy and breach rate, were analyzed using a random-effects model. Risk of bias was assessed using the Newcastle-Ottawa Scale.

RESULTS

The overall accuracy of PS insertion using RG, based on 37 studies involving 3,837 patients and 22,117 PS, is 97.9%, with a breach rate of 0.021. RG demonstrated superior accuracy compared to FHG and CTG, with breach rates of 3.4 and 0.015 respectively for RG versus FHG, and 3.8 and 0.026 for RG versus CTG. Additionally, RG was associated with reduced mean estimated blood loss compared to CTG, indicating improved safety.

CONCLUSIONS

The RG is associated with enhanced accuracy of PS insertion and reduced breach rates over other methods. However, additional randomized controlled trials comparing these modalities are needed for further validation.

PROSPERO REGISTRATION

CRD42023483997.

Pushing the Limits of Minimally Invasive Spine Surgery-From Preoperative to Intraoperative to Postoperative Management

The introduction of minimally invasive surgery ushered in a new era of spine surgery by minimizing the undue iatrogenic injury, recovery time, and blood loss, among other complications, of traditional open procedures. Over time, technological advancements have further refined the care of the operative minimally invasive spine patient. Moreover, pre-, and postoperative care have also undergone significant change by way of artificial intelligence risk stratification, advanced imaging for surgical planning and patient selection, postoperative recovery pathways, and digital health solutions. Despite these advancements, challenges persist necessitating ongoing research and collaboration to further optimize patient care in minimally invasive spine surgery.

Clinical Outcome Analysis of Robot-Assisted Pedicle Screw Insertion in the Treatment of Ankylosing Spondylitis Complicated with Spinal Fractures

BACKGROUND

Vague spinal anatomical landmarks in patients with ankylosing spondylitis (AS) make intraoperative insertion of pedicle screws difficult under direct vision. Currently, the clinical outcome is significantly improved with robot guidance. This study aims to explore the efficacy of robot-assisted pedicle screw insertion in treating AS combined with spinal fractures.

METHODS

Forty patients (341 screws) who underwent pedicle screw insertion with AS complicated with spinal fractures were included. According to different surgical methods, 16 patients (135 screws) were classified into the robot group and 24 (206 screws) into the free-hand group. Intraoperative blood loss, operative duration, and adverse events were compared between the 2 groups. Gertzbein and Robbins classification was used to classify the accuracy of screw position. Clinical outcomes were evaluated by Visual Analog Scale, Japanese Orthopedic Association, and Oswestry Disability Index.

RESULTS

No statistically significant differences between baseline data of the groups. The difference in the blood loss between groups wasn't significant, nor was the operative duration. No severe adverse events related to pedicle screw insertion were reported in either group. Notably, the accuracy of screw insertion was significantly higher in the robot group (129/135) than in the free-hand group (182/206). The lateral perforation prevalence didn't differ among groups. Visual Analog Scale in the third month postoperatively was lower in the robot group than in the free-hand group, with a significant difference.

CONCLUSIONS

The study demonstrates statistically superior accuracy and surgical outcome of robot-assisted pedicle screw insertion in the treatment of AS complicated with spinal fractures compared with the traditional free-hand operation.

Comparative efficacy of robotic-assisted and freehand techniques for pedicle screw placement in spinal disorders: a meta-analysis and systematic review

The efficacy and safety of robotic-assisted pedicle screw placement compared to traditional fluoroscopy-guided techniques are of great interest in the field of spinal surgery. This systematic review and meta-analysis aimed to compare the outcomes of these two methods in patients with spinal diseases. Following the PRISMA guidelines, we conducted a systematic search across PubMed, Embase, Web of Science, and Cochrane Library. We included randomized controlled trials comparing robotic-assisted and fluoroscopy-guided pedicle screw placement in patients with spinal diseases. Outcome measures included the accuracy of pedicle screw placement, postoperative complication rates, intraoperative radiation exposure time, and duration of surgery. Data were analyzed using Stata software. Our analysis included 12 studies. It revealed significantly higher accuracy in pedicle screw placement with robotic assistance (odds ratio [OR] = 2.83, 95% confidence interval [CI] = 2.20-3.64, P < 0.01). Postoperative complication rates, intraoperative radiation exposure time, and duration of surgery were similar between the two techniques (OR = 0.72, 95% CI = 0.31 to 1.68, P = 0.56 for complication rates; weighted mean difference [WMD] = - 0.13, 95% CI = - 0.93 to 0.68, P = 0.86 for radiation exposure time; WMD = 0.30, 95% CI = - 0.06 to 0.66, P = 0.06 for duration of surgery). Robotic-assisted pedicle screw placement offers superior placement accuracy compared to fluoroscopy-guided techniques. Postoperative complication rates, intraoperative radiation exposure time, and duration of surgery were comparable for both methods. Future studies should explore the potential for fewer complications with the robotic-assisted approach as suggested by the lower point estimate.

Stereotactic body radiation therapy for spinal metastases: A new standard of care

Advancements in systemic therapies for patients with metastatic cancer have improved overall survival and, hence, the number of patients living with spinal metastases. As a result, the need for more versatile and personalized treatments for spinal metastases to optimize long-term pain and local control has become increasingly important. Stereotactic body radiation therapy (SBRT) has been developed to meet this need by providing precise and conformal delivery of ablative high-dose-per-fraction radiation in few fractions while minimizing risk of toxicity. Additionally, advances in minimally invasive surgical techniques have also greatly improved care for patients with epidural disease and/or unstable spines, which may then be combined with SBRT for durable local control. In this review, we highlight the indications and controversies of SBRT along with new surgical techniques for the treatment of spinal metastases.

Robotic-Assisted Versus Fluoroscopic-Guided Surgery on the Accuracy of Spine Pedicle Screw Placement: A Systematic Review and Meta-Analysis

Spinal fusion is a common method by which surgeons decrease instability and deformity of the spinal segment targeted. Pedicle screws are vital tools in fusion surgeries and advancements in technology have introduced several modalities of screw placement. Our objective was to evaluate the accuracy of pedicle screw placement in robot-assisted (RA) versus fluoroscopic-guided (FG) techniques. The PubMed and Cochrane Library databases were systematically reviewed from January 2007 through to August 8, 2022, to identify relevant studies. The accuracy of pedicle screw placement was determined using the Gertzbein-Robbins (GR) classification system. Facet joint violation (FJV), total case radiation dosage, total case radiation time, total operating room (OR) time, and total case blood loss were collected. Twenty-one articles fulfilled the inclusion criteria. Successful screw accuracy (GR Grade A or B) was found to be 1.02 (95% confidence interval: 1.01 - 1.04) times more likely with the RA technique. In defining accuracy solely based on the GR Grade A criteria, screws placed with RA were 1.10 (95% confidence interval: 1.06 - 1.15) times more likely to be accurate. There was no significant difference between the two techniques with respect to blood loss (Hedges' g: 1.16, 95% confidence interval: -0.75 to 3.06) or case radiation time (Hedges' g: -0.34, 95% CI: -1.22 to 0.53). FG techniques were associated with shorter operating room times (Hedges' g: -1.03, 95% confidence interval: -1.76 to -0.31), and higher case radiation dosage (Hedges' g: 1.61, 95% confidence interval: 1.11 to 2.10). This review suggests that RA may slightly increase pedicle screw accuracy and decrease per-case radiation dosage compared to FG techniques. However, total operating times for RA cases are greater than those for FG cases.

Advancements in robotic surgery: innovations, challenges and future prospects

The use of robots has revolutionized healthcare, wherein further innovations have led to improved precision and accuracy. Conceived in the late 1960s, robot-assisted surgeries have evolved to become an integral part of various surgical specialties. Modern robotic surgical systems are equipped with highly dexterous arms and miniaturized instruments that reduce tremors and enable delicate maneuvers. Implementation of advanced materials and designs along with the integration of imaging and visualization technologies have enhanced surgical accuracy and made robots safer and more adaptable to various procedures. Further, the haptic feedback system allows surgeons to determine the consistency of the tissues they are operating upon, without physical contact, thereby preventing injuries due to the application of excess force. With the implementation of teleoperation, surgeons can now overcome geographical limitations and provide specialized healthcare remotely. The use of artificial intelligence (AI) and machine learning (ML) aids in surgical decision-making by improving the recognition of minute and complex anatomical structures. All these advancements have led to faster recovery and fewer complications in patients. However, the substantial cost of robotic systems, their maintenance, the size of the systems and proper surgeon training pose major challenges. Nevertheless, with future advancements such as AI-driven automation, nanorobots, microscopic incision surgeries, semi-automated telerobotic systems, and the impact of 5G connectivity on remote surgery, the growth curve of robotic surgery points to innovation and stands as a testament to the persistent pursuit of progress in healthcare.

The role of robotic surgery in neurological cases: A systematic review on brain and spine applications

The application of robotic surgery technologies in neurological surgeries resulted in some advantages compared to traditional surgeries, including higher accuracy and dexterity enhancement. Its success in various surgical fields, especially in urology, cardiology, and gynecology surgeries was reported in previous studies, and similar advantages in neurological surgeries are expected. Surgeries in the central nervous system with the pathology of millimeters through small working channels around vital tissue need especially high precision. Applying robotic surgery is therefore an interesting dilemma for these situations. This article reviews various studies published on the application of brain and spine robotic surgery and discusses the current application of robotic technology in neurological cases.

[Translated article] The role of minimally invasive spine surgery in the treatment of vertebral metastasis: A narrative review

BACKGROUND

Spinal metastases are a very common problem which dramatically affects the quality of life of cancer patients. The objective of this review is to address the issue of how minimally invasive surgery can play an important role in treating this pathology.

METHODS

A literature review was performed, searching in the Google Scholar, PubMed, Scopus and Cochrane databases. Relevant and quality papers published within the last 10 years were included in the review.

RESULTS

After screening the 2184 initially identified registers, a total of 24 articles were included for review.

CONCLUSION

Minimally invasive spine surgery is specially convenient for fragile cancer patients with spinal metastases, because of its reduced comorbidity compared to conventional open surgery. Technological advances in surgery, such as navigation and robotics, improve accuracy and safety in this technique.

The role of minimally invasive spine surgery in the treatment of vertebral metastasis: A narrative review

BACKGROUND

Spinal metastases are a very common problem which dramatically affects the quality of life of cancer patients. The objective of this review is to address the issue of how minimally invasive surgery can play an important role in treating this pathology.

METHODS

A literature review was performed, searching in the Google Scholar, PubMed, Scopus and Cochrane databases. Relevant and quality papers published within the last 10 years were included in the review.

RESULTS

After screening the 2184 initially identified registers, a total of 24 articles were included for review.

CONCLUSION

Minimally invasive spine surgery is specially convenient for fragile cancer patients with spinal metastases, because of its reduced comorbidity compared to conventional open surgery. Technological advances in surgery, such as navigation and robotics, improve accuracy and safety in this technique.

Pedicle Screw Placement Accuracy in Robot-Assisted Spinal Fusion in a Multicenter Study

Pedicle screw fixation is a spinal fusion technique that involves the implantation of screws into vertebral pedicles to restrict movement between those vertebrae. The objective of this research is to measure pedicle screw placement accuracy using a novel automated measurement system that directly compares the implanted screw location to the planned target in all three anatomical views. Preoperative CT scans were used to plan the screw trajectories in 122 patients across four surgical centers. Postoperative scans were fused to the preoperative plan to quantify placement accuracy using an automated measurement algorithm. The mean medial-lateral and superior-inferior deviations in the pedicle region for 500 screws were 1.75 ± 1.36 mm and 1.52 ± 1.26 mm, respectively. These deviations were measured using an automated system and were statistically different from manually determined values. The uncertainty associated with the fusion of preoperative to postoperative images was also quantified to better understand the screw-to-plan accuracy results. This study uses a novel automated measurement system to quantify screw placement accuracy as it relates directly to the planned target location, instead of analyzing for breaches of the pedicle, to quantify the validity of using of a robotic-guidance system for accurate pedicle screw placement.

Robotics and navigation in spine surgery: A narrative review

Introduction

In recent decades, there has been a rising trend of spinal surgical interventional techniques, especially Minimally Invasive Spine Surgery (MIS), to improve the quality of life in an effective and safe manner. However, MIS techniques tend to be difficult to adapt and are associated with an increased risk of radiation exposure. This led to the development of 'computer-assisted surgery' in 1983, which integrated CT images into spinal procedures evolving into the present day robotic-assisted spine surgery. The authors aim to review the development of spine surgeries and provide an overview of the benefits offered. It includes all the comparative studies available to date.

Methods

The manuscript has been prepared as per "SANRA-a scale for the quality assessment of narrative review articles". The authors searched Pubmed, Embase, and Scopus using the terms "(((((Robotics) OR (Navigation)) OR (computer assisted)) OR (3D navigation)) OR (Freehand)) OR (O-Arm)) AND (spine surgery)" and 68 articles were included for analysis excluding review articles, meta-analyses, or systematic literature.

Results

The authors noted that 49 out of 68 studies showed increased precision of pedicle screw insertion, 10 out of 19 studies show decreased radiation exposure, 13 studies noted decreased operative time, 4 out of 8 studies showed reduced hospital stay and significant reduction in rates of infections, neurological deficits, the need for revision surgeries, and rates of radiological ASD, with computer-assisted techniques.

Conclusion

Computer-assisted surgeries have better accuracy of pedicle screw insertion, decreased blood loss and operative time, reduced radiation exposure, improved functional outcomes, and lesser complications.

Impact of Navigation on 30-Day Outcomes for Adult Spinal Deformity Surgery

STUDY DESIGN

Retrospective database study.

OBJECTIVE

Navigation has been increasingly used to treat degenerative disease, with positive radiographic and clinical outcomes and fewer adverse events and reoperations, despite increased operative time. However, short-term analysis on treating adult spinal deformity (ASD) surgery with navigation is limited, particularly using large nationally represented cohorts. This is the first large-scale database study to compare 30-day readmission, reoperation, morbidity, and value-per-operative time for navigated and conventional ASD surgery.

METHODS

Adults were identified in the National Surgical Quality Improvement Program (NSQIP) database. Multivariate regression was used to compare outcomes between navigated and conventional surgery and to control for predictors and baseline differences.

RESULTS

3190 ASD patients were included. Navigated and conventional patients were similar. Navigated cases had greater operative time (405 vs 320 min) and mean RVUs per case (81.3 vs 69.7), and had more supplementary pelvic fixations (26.1 vs 13.4%) and osteotomies (50.3 vs 27.7%) (P <.001).In univariate analysis, navigation had greater reoperation (9.9 vs 5.2%, P = .011), morbidity (57.8 vs 46.8%, P = .007), and transfusion (52.2 vs 41.8%, P = .010) rates. Readmission was similar (11.9 vs 8.4%). In multivariate analysis, navigation predicted reoperation (OR = 1.792, P = .048), but no longer predicted morbidity or transfusion. Most reoperations were infectious and hardware-related.

CONCLUSIONS

Despite controlling for patient-related and procedural factors, navigation independently predicted a 79% increased odds of reoperation but did not predict morbidity or transfusion. Readmission was similar between groups. This is explained, in part, by greater operative time and transfusion, which are risk factors for infection. Reoperation most frequently occurred for wound- and hardware-related reasons, suggesting navigation carries an increased risk of infectious-related events beyond increased operative time.

Intraoperative Cone-Beam Computed Tomography Assessment of Spinal Pedicle Screws Placement Precision Is in Full Agreement with Postoperative Computed Tomography Assessment

OBJECTIVE

To assess agreement between pedicle screw placement evaluated on postoperative computed tomography (CT) and on intraoperative cone-beam CT (CBCT) and compare procedure characteristics when using first-generation and second-generation robotic C-arm systems in the hybrid operating room.

METHODS

All patients who received pedicle screws for spinal fusion at our institution between June 2009 and September 2019 and underwent intraoperative CBCT and postoperative CT were included. The CBCT and CT images were reviewed by 2 surgeons to assess the screw placement using the Gertzbein-Robbins and the Heary classifications. Intermethod agreement of screw placement classifications as well as interrater agreement were assessed using Brennan-Prediger and Gwet agreement coefficients. Procedure characteristics using first-generation and second-generation generation robotic C-arm systems were compared.

RESULTS

Fifty-seven patients were treated with 315 pedicle screws at thoracic, lumbar, and sacral levels. No screw had to be repositioned. On CBCT, accurate placement was found for 309 screws (98.1%) using the Gertzbein-Robbins classification and 289 (91.7%) using the Heary classification and on CT, these were 307 (97.4%) and 293 (93.0%), respectively. Intermethod between CBCT and CT and interrater agreements between the 2 raters were almost perfect (>0.90) for all assessment. There were no significant differences in mean radiation dose (P = 0.83) and fluoroscopy time (P = 0.82), but length of surgery using the second-generation system was estimated at 107.7 minutes (95% confidence interval, 31.9-183.5 minutes; P = 0.006) shorter.

CONCLUSIONS

Intraoperative CBCT provides accurate assessment of pedicle screw placement and enables intraoperative repositioning of misplaced screws.

Artificial intelligence in spine surgery

The continuous progress of research and clinical trials has offered a wide variety of information concerning the spine and the treatment of the different spinal pathologies that may occur. Planning the best therapy for each patient could be a very difficult and challenging task as it often requires thorough processing of the patient's history and individual characteristics by the clinician. Clinicians and researchers also face problems when it comes to data availability due to patients' personal information protection policies. Artificial intelligence refers to the reproduction of human intelligence via special programs and computers that are trained in a way that simulates human cognitive functions. Artificial intelligence implementations to daily clinical practice such as surgical robots that facilitate spine surgery and reduce radiation dosage to medical staff, special algorithms that can predict the possible outcomes of conservative versus surgical treatment in patients with low back pain and disk herniations, and systems that create artificial populations with great resemblance and similar characteristics to real patients are considered to be a novel breakthrough in modern medicine. To enhance the body of the related literature and inform the readers on the clinical applications of artificial intelligence, we performed this review to discuss the contribution of artificial intelligence in spine surgery and pathology.

Robot-assisted percutaneous vertebroplasty for osteoporotic vertebral compression fractures: a retrospective matched-cohort study

PURPOSE

This study aims to introduce the principle, clinical efficacy, and learning curve of robot-assisted percutaneous vertebroplasty (PVP).

METHODS

Forty-two patients who underwent robot-assisted single-level PVP were analyzed retrospectively and 42 age-matched patients using freehand technique were selected as the control group. The visual analog scale, operation time, radiation exposure, accuracy, and learning curve were analyzed.

RESULTS

The puncture time and total operation time were significantly shorter, and the puncture and total fluoroscopy number were fewer in the robot group. The deviation between pre-operative planned and actual puncture trajectory well met clinical requirement. The puncture time, total operation time, and puncture fluoroscopy number were significantly more in early cases than in later cases in the robot group.

CONCLUSION

The robot-assisted pedicle puncture technique shortens the operation time and reduces radiation exposure, and the accuracy meets the clinical requirement in PVP. The learning curve is short and not steep.

Safety and Accuracy of Freehand Pedicle Screw Placement and the Role of Intraoperative O-Arm: A Single-Institution Experience

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

The aim was to investigate the accuracy of pedicle screw placement by freehand technique and to compare revision surgery rates among three different imaging verification pathways.

SUMMARY OF BACKGROUND DATA

Studies comparing different imaging modalities in freehand screw placement surgery are limited.

MATERIALS AND METHODS

A single-institution retrospective chart review identified adult patients who underwent freehand pedicle screw placement in the thoracic, lumbar or sacral levels. Patients were stratified into three cohorts based on the intraoperative imaging modality used to assess the accuracy of screw position: intraoperative X-rays (cohort 1); intraoperative O-arm (cohort 2); or intraoperative computed tomography (CT)-scan (cohort 3). Postoperative CT scans were performed on all patients in cohorts 1 and 2. Postoperative CT scan was not required in cohort 3. Screw accuracy was assessed using the Gertzbein-Robbins grading system.

RESULTS

A total of 9179 pedicle screws were placed in the thoracic or lumbosacral spine in 1311 patients. 210 (2.3%) screws were identified as Gertzbein-Robbins grades C-E on intraoperative/postoperative CT scan, 137 thoracic screws, and 73 lumbar screws ( P <0.001). Four hundred and nine patients underwent placement of 2754 screws followed by intraoperative X-ray (cohort 1); 793 patients underwent placement of 5587 screws followed by intraoperative O-arm (cohort 2); and 109 patients underwent placement of 838 screws followed by intraoperative CT scan (cohort 3). Postoperative CT scans identified 65 (2.4%) and 127 (2.3%) malpositioned screws in cohorts 1 and 2, respectively. Eleven screws (0.12%) were significantly malpositioned and required a second operation for screw revision. Nine patients (0.69%) required revision operations: eight of these patients were from cohort 1 and one patient was from cohort 2.

CONCLUSION

When compared to intraoperative X-ray, intraoperative O-arm verification decreased the revision surgery rate for malpositioned screws from 0.37% to 0.02%. In addition, our analysis suggests that the use of intraoperative O-arm can obviate the need for postoperative CT scans.

Robot and working tube-assisted invasion-controlled surgery for spinal metastases

Objective

This study aims to highlight the use of robots in surgery and that of tube-assisted minimally invasive surgery for spinal metastases, as well as elaborate on the concept of invasion-controlled surgery (ICS).

Summary of background

Many patients with spinal metastasis cancer cannot afford serious complications when undergoing traditional open surgery because of their poor physical condition. Robots and minimally invasive technology have been introduced into the field of spine surgery and they have shown significant advantages.

Methods

Six patients who underwent robot and working tube-assisted ICS for spinal metastases. Relevant demographic, medical, surgical, and postoperative data were collected from medical records and analyzed.

Results

Mean operative time was 3.8 h and the mean length of the surgical incision was 4.9 cm. The mean estimated blood loss was 400 ml. The mean bedtime and hospital length of stay were 3.2 days and 6.5 days, respectively. No obvious complications were reported during treatment. The mean accuracy of screw placement was 98%. The mean time for further system treatment after surgery was 5.8 days. All patients experienced significant pain relief. The mean preoperative visual analog scale (VAS) was 7.83 points. The mean VAS at 1 day, 1 week, and 1 month after surgery were 2.83, 1.83, and 1.17 points, respectively. Frankel grade was improved in five of six patients. One patient preoperatively with Frankel grade D was the same postoperatively.

Conclusion

The concept of ICS is suitable for patients with spinal metastases. Robot and working tube-assisted ICS for spinal metastases is one of the safest and most effective treatment methods.

Spinal robotics in cervical spine surgery: a systematic review with key concepts and technical considerations

OBJECTIVE

Spinal robotics for thoracolumbar procedures, predominantly employed for the insertion of pedicle screws, is currently an emerging topic in the literature. The use of robotics in instrumentation of the cervical spine has not been broadly explored. In this review, the authors aimed to coherently synthesize the existing literature of intraoperative robotic use in the cervical spine and explore considerations for future directions and developments in cervical spinal robotics.

METHODS

A literature search in the Web of Science, Scopus, and PubMed databases was performed for the purpose of retrieving all articles reporting on cervical spine surgery with the use of robotics. For the purposes of this study, randomized controlled trials, nonrandomized controlled trials, retrospective case series, and individual case reports were included. The Newcastle-Ottawa Scale was utilized to assess risk of bias of the studies included in the review. To present and synthesize results, data were extracted from the included articles and analyzed using the PyMARE library for effect-size meta-analysis.

RESULTS

On careful review, 6 articles published between 2016 and 2022 met the inclusion/exclusion criteria, including 1 randomized controlled trial, 1 nonrandomized controlled trial, 2 case series, and 2 case reports. These studies featured a total of 110 patients meeting the inclusion criteria (mean age 53.9 years, range 29-77 years; 64.5% males). A total of 482 cervical screws were placed with the use of a surgical robot, which yielded an average screw deviation of 0.95 mm. Cervical pedicle screws were the primary screw type used, at a rate of 78.6%. According to the Gertzbein-Robbins classification, 97.7% of screws in this review achieved a clinically acceptable grade. The average duration of surgery, blood loss, and postoperative length of stay were all decreased in minimally invasive robotic surgery relative to open procedures. Only 1 (0.9%) postoperative complication was reported, which was a surgical site infection, and the mean length of follow-up was 2.7 months. No mortality was reported.

CONCLUSIONS

Robot-assisted cervical screw placement is associated with acceptable rates of clinical grading, operative time, blood loss, and postoperative complications-all of which are equal to or improved relative to the metrics seen in the conventional use of fluoroscopy or computer-assisted navigation for cervical screw placement.

Basis for error in stereotactic and computer-assisted surgery in neurosurgical applications: literature review

Technological advancements in optoelectronic motion capture systems have allowed for the development of high-precision computer-assisted surgery (CAS) used in cranial and spinal surgical procedures. Errors generated sequentially throughout the chain of components of CAS may have cumulative effect on the accuracy of implant and instrumentation placement - potentially affecting patient outcomes. Navigational integrity and maintenance of fidelity of optoelectronic data is the cornerstone of CAS. Error reporting measures vary between studies. Understanding error generation, mechanisms of propagation, and how they relate to workflow can assist clinicians in error mitigation and improve accuracy during navigation in neurosurgical procedures. Diligence in planning, fiducial positioning, system registration, and intra-operative workflow have the potential to improve accuracy and decrease disparity between planned and final instrumentation and implant position. This study reviews the potential errors associated with each step in computer-assisted surgery and provides a basis for disparity in intrinsic accuracy versus achieved accuracy in the clinical operative environment.

A Novel Point Set Registration-Based Hand-Eye Calibration Method for Robot-Assisted Surgery

Pedicle screw insertion with robot assistance dramatically improves surgical accuracy and safety when compared with manual implantation. In developing such a system, hand-eye calibration is an essential component that aims to determine the transformation between a position tracking and robot-arm systems. In this paper, we propose an effective hand-eye calibration method, namely registration-based hand-eye calibration (RHC), which estimates the calibration transformation via point set registration without the need to solve the AX=XB equation. Our hand-eye calibration method consists of tool-tip pivot calibrations in two-coordinate systems, in addition to paired-point matching, where the point pairs are generated via the steady movement of the robot arm in space. After calibration, our system allows for robot-assisted, image-guided pedicle screw insertion. Comprehensive experiments are conducted to verify the efficacy of the proposed hand-eye calibration method. A mean distance deviation of 0.70 mm and a mean angular deviation of 0.68° are achieved by our system when the proposed hand-eye calibration method is used. Further experiments on drilling trajectories are conducted on plastic vertebrae as well as pig vertebrae. A mean distance deviation of 1.01 mm and a mean angular deviation of 1.11° are observed when the drilled trajectories are compared with the planned trajectories on the pig vertebrae.

A Comparison of Spinal Robotic Systems and Pedicle Screw Accuracy Rates: Review of Literature and Meta-Analysis

Introduction  The motivation to improve accuracy and reduce complication rates in spinal surgery has driven great advancements in robotic surgical systems, with the primary difference between the newer generation and older generation models being the presence of an optical camera and multijointed arm. This study compares accuracy and complication rates of pedicle screw placement in older versus newer generation robotic systems reported in the literature. Methods  We performed a systemic review and meta-analysis describing outcomes of pedicle screw placement with robotic spine surgery. We assessed the robustness of these findings by quantifying levels of cross-study heterogeneity and publication bias. Finally, we performed meta-regression to test for associations between pedicle screw accuracy and older versus newer generation robotic spine system usage. Results  Average pedicle screw placement accuracy rates for old and new generation robotic platforms were 97 and 99%, respectively. Use of new generation robots was significantly associated with improved pedicle screw placement accuracy ( p  = 0.03). Conclusion  Accuracy of pedicle screw placement was high across all generations of robotic surgical systems. However, newer generation robots were shown to be significantly associated with accurate pedicle screw placement, showing the benefits of upgrading robotic systems with a real-time optical camera and multijointed arm.

Comparison of the Accuracy and Safety of TiRobot-Assisted and Fluoroscopy-Assisted Percutaneous Pedicle Screw Placement for the Treatment of Thoracolumbar Fractures

OBJECTIVE

Studies have compared the safety and accuracy of robot-assisted techniques for inserting conventional open pedicle screws for spinal surgery. However, no relevant studies have confirmed that robot-assisted percutaneous screw placement is better than fluoroscopic percutaneous screw placement for the treatment of thoracolumbar fractures. This study compared the accuracy and safety of TiRobot-assisted percutaneous pedicle screw placement with those of the fluoroscopy-assisted percutaneous technique for the treatment of thoracolumbar fractures.

METHODS

This retrospective study included 126 patients with thoracolumbar fractures who underwent percutaneous pedicle screw placement. Sixty-five patients were treated with the TiRobot-assisted technique and 61 patients were treated with the fluoroscopy-assisted technique. Patient demographics, accuracy of screw placement (according to the Gertzbein and Robbins scale of grades A to E), screw insertion angle, radiation exposure, surgical time, intraoperative blood loss, length of hospital stay, incision length, hospital expenses, surgical site infection, and neurological injury of the TiRobot-assisted and fluoroscopy-assisted groups were compared using Student's t-test, Pearson χ² test, or Fisher's exact test.

RESULTS

A total of 729 screws were placed (TiRobot-assisted group: 374 screws; fluoroscopy-assisted group: 355 screws). In the TiRobot-assisted group, 82.8% of screws were optimally positioned (grade A); however, the placement grades of the remaining screws were categorized as grade B (13.3%), grade C (3.2%), and grade D (0.5%). In the fluoroscopy-assisted group, 66.7% of the screws were optimally positioned (grade A); however, the placement grades of the remaining screws were categorized as grade B (21.4%), grade C (7.6%), grade D (3.6%), and grade E (0.5%). The proportion of clinically acceptable screws (grade A or B) was greater in the TiRobot-assisted group than in the fluoroscopy-assisted group. Additionally, the TiRobot-assisted group had a significantly larger mean screw insertion angle (22.27° ± 5.48° vs 20.55° ± 5.15°), larger incision length (13.86 ± 1.24 cm vs 12.77 ± 1.43 cm), and higher hospital expenses (69061.55 ± 7166.60 yuan vs 59383.85 ± 5019.64 yuan) than the fluoroscopy-assisted group. There were no significant differences in the intraoperative blood loss, length of hospital stay, and rates of surgical site infection and neurological injury in both groups (p > 0.05). However, the TiRobot-assisted group had significantly better surgical times, radiation times, and radiation exposure than the fluoroscopy-assisted group (p < 0.05).

CONCLUSIONS

Percutaneous TiRobot-assisted pedicle screw placement is a safe, useful, and potentially more accurate alternative to the percutaneous fluoroscopy-assisted technique for treating thoracolumbar fractures.

Robotics Reduces Radiation Exposure in Minimally Invasive Lumbar Fusion Compared With Navigation

STUDY DESIGN

Retrospective cohort.

OBJECTIVE

To compare robotics and navigation for minimally invasive elective lumbar fusion in terms of radiation exposure and time demand.

SUMMARY OF BACKGROUND DATA

Although various studies have been conducted to demonstrate the benefits of both navigation and robotics over fluoroscopy in terms of radiation exposure, literature is lacking in studies comparing robotics versus navigation.

MATERIALS AND METHODS

Patients who underwent elective one-level or two-level minimally invasive transforaminal lumbar interbody fusion (TLIF) by a single surgeon using navigation (Stryker SpineMask) or robotics (ExcelsiusGPS) were included (navigation 2017-2019, robotics 2019-2021, resulting in prospective cohorts of consecutive patients for each modality). All surgeries had the intraoperative computed tomography workflow. The two cohorts were compared for radiation exposure [fluoroscopy time and radiation dose: image capture, surgical procedure, and overall) and time demand (time for setup and image capture, operative time, and total operating room (OR) time].

RESULTS

A total of 244 patients (robotics 111, navigation 133) were included. The two cohorts were similar in terms of baseline demographics, primary/revision surgeries, and fusion levels. For one-level TLIF, total fluoroscopy time, total radiation dose, and % of radiation for surgical procedure were significantly less with robotics compared with navigation (20 vs. 25 s, P <0.001; 38 vs. 42 mGy, P =0.05; 58% vs. 65%, P =0.021). Although time for setup and image capture was significantly less with robotics (22 vs. 25 min, P <0.001) and operative time was significantly greater with robotics (103 vs. 93 min, P <0.001), there was no significant difference in the total OR time (145 vs. 141 min, P =0.25). Similar findings were seen for two-level TLIF as well.

CONCLUSION

Robotics for minimally invasive TLIF, compared with navigation, leads to a significant reduction in radiation exposure both to the surgeon and patient, with no significant difference in the total OR time.

Robot-assisted and augmented reality-assisted spinal instrumentation: a systematic review and meta-analysis of screw accuracy and outcomes over the last decade

OBJECTIVE

The use of technology-enhanced methods in spine surgery has increased immensely over the past decade. Here, the authors present the largest systematic review and meta-analysis to date that specifically addresses patient-centered outcomes, including the risk of inaccurate screw placement and perioperative outcomes in spinal surgeries using robotic instrumentation and/or augmented reality surgical navigation (ARSN).

METHODS

A systematic review of the literature in the PubMed, EMBASE, Web of Science, and Cochrane Library databases spanning the last decade (January 2011-November 2021) was performed to present all clinical studies comparing robot-assisted instrumentation and ARSN with conventional instrumentation techniques in lumbar spine surgery. The authors compared these two technologies as they relate to screw accuracy, estimated blood loss (EBL), intraoperative time, length of stay (LOS), perioperative complications, radiation dose and time, and the rate of reoperation.

RESULTS

A total of 64 studies were analyzed that included 11,113 patients receiving 20,547 screws. Robot-assisted instrumentation was associated with less risk of inaccurate screw placement (p < 0.0001) regardless of control arm approach (freehand, fluoroscopy guided, or navigation guided), fewer reoperations (p < 0.0001), fewer perioperative complications (p < 0.0001), lower EBL (p = 0.0005), decreased LOS (p < 0.0001), and increased intraoperative time (p = 0.0003). ARSN was associated with decreased radiation exposure compared with robotic instrumentation (p = 0.0091) and fluoroscopy-guided (p < 0.0001) techniques.

CONCLUSIONS

Altogether, the pooled data suggest that technology-enhanced thoracolumbar instrumentation is advantageous for both patients and surgeons. As the technology progresses and indications expand, it remains essential to continue investigations of both robotic instrumentation and ARSN to validate meaningful benefit over conventional instrumentation techniques in spine surgery.

Association of robot-assisted techniques with the accuracy rates of pedicle screw placement: A network pooling analysis

BACKGROUND

Traditional paired meta-analyses have yielded inconsistent results for the safety and effectiveness of robotic-assisted pedicle screw placement due to the high heterogeneity within studies. This study evaluated the clinical effectiveness and safety of robotic-assisted pedicle screw placement.

METHODS

The Embase, PubMed, and Cochrane Library databases were searched with no language limitations from inception to Jan 4, 2022. Odds ratio (OR), mean difference (MD), and 95% confidence interval (CI) were used to report results. The main outcomes were accuracy of pedicle screw placement, proximal facet joint violation, and complications. The study protocol was published in PROSPERO (CRD42022301417).

FINDINGS

26 trials including 2046 participants evaluating robotic-assisted pedicle screw placement were included in this study. Our pooled results showed that Renaissance (OR 2.86; [95% CI 1.79 to 4.57]) and TiRobot (OR 3.10; [95% CI 2.19 to 4.40]) yielded higher rates of perfect pedicle screw insertion (Grades A) than the conventional freehand technique. Renaissance (OR 2.82; [95% CI 1.51 to 5.25]) and TiRobot (OR 4.58; [95% CI 2.65 to 7.89]) yielded higher rates of clinically acceptable pedicle screw insertion (Grades A+B). However, ROSA, SpineAssist, and Orthobot were not associated with higher perfect pedicle screw insertion and clinically acceptable pedicle screw insertion rates. Robot-assisted techniques were associated with low rates of proximal facet joint violation (OR 0.18; [95% CI 0.10 to 0.32]; I²:9.55%) and overall complications (OR 0.38; [95% CI 0.23 to 0.63]; I²:27.05%). Moreover, robot-assisted techniques were associated with lower radiation doses (MD -14.38; [95% CI -25.62 to -3.13]; I²:100.00%).

INTERPRETATION

Our findings suggest that only Renaissance and TiRobot systems are associated with high accuracy rates of pedicle screw placement. Robotic-assisted techniques hold great promise in spinal surgery due to their safety and effectiveness.

FUNDING

This work was supported by grants from the National Natural Science Foundation of China (No. 81871818), Tangdu Hospital Seed Talent Program (Fei-Long Wei) and Natural Science Basic Research Plan in Shaanxi Province of China (No.2019JM-265).

When giants talk; robotic dialog during thoracolumbar and sacral surgery

Background

Spinal trauma patients treated in a specialized hybrid operating room (OR) using two robotic systems communicating during surgery.

Methods

Retrospective review of patients with thoracolumbar or sacral fractures who underwent surgical fixation between Jan 2017 to Jan 2020 with robotic-guided percutaneous pedicle screw insertion in the specialized hybrid OR with Robotic flat panel 3D C-arm (ArtisZeego) for intraoperative interventional imaging connected with the robotic-guidance platform Renaissance (Mazor Robotics).

Results

Twenty eight surgeries were performed in 27 patients; 23 with traumatic spinal fractures, 4 with multi-level thoracolumbar compression fractures due to severe osteoporosis. Average patient age 49 (range 12–86). Average radiation exposure time 40 s (range 12–114 s). Average radiation exposure dose 11,584 ± SD uGym² (range 4454–58,959). Lumber levels operated on were between T5 and S2 (shortest three vertebras and longest eight vertebras). 235 (range 5–11) trajectories were performed. All trajectories were accurate in all cases percutaneous pedicle screws placement was correct, without breach noted at the pedicle in any of the cases. No major complications reported. In all cases, follow-up X-rays showed adequate fracture reduction with restoration.

Conclusions

Merging of surgical robotics technologies increases patient safety and surgeon and patient confidence in percutaneous spine traumatic procedures.

Comparative Analysis of Optoelectronic Accuracy in the Laboratory Setting Versus Clinical Operative Environment: A Systematic Review

STUDY DESIGN

Systematic review.

OBJECTIVES

The optoelectronic camera source and data interpolation process serve as the foundation for navigational integrity in robotic-assisted surgical platforms. The current systematic review serves to provide a basis for the numerical disparity observed when comparing the intrinsic accuracy of optoelectronic cameras versus accuracy in the laboratory setting and clinical operative environments.

METHODS

Review of the PubMed and Cochrane Library research databases was performed. The exhaustive literature compilation obtained was then vetted to reduce redundancies and categorized into topics of intrinsic accuracy, registration accuracy, musculoskeletal kinematic platforms, and clinical operative platforms.

RESULTS

A total of 465 references were vetted and 137 comprise the basis for the current analysis. Regardless of application, the common denominators affecting overall optoelectronic accuracy are intrinsic accuracy, registration accuracy, and application accuracy. Intrinsic accuracy equaled or was less than 0.1 mm translation and 0.1 degrees rotation per fiducial. Controlled laboratory platforms reported 0.1 to 0.5 mm translation and 0.1 to 1.0 degrees rotation per array. Accuracy in robotic-assisted spinal surgery reported 1.5 to 6.0 mm translation and 1.5 to 5.0 degrees rotation when comparing planned to final implant position.

CONCLUSIONS

Navigational integrity and maintenance of fidelity of optoelectronic data is the cornerstone of robotic-assisted spinal surgery. Transitioning from controlled laboratory to clinical operative environments requires an increased number of steps in the optoelectronic kinematic chain and error potential. Diligence in planning, fiducial positioning, system registration and intra-operative workflow have the potential to improve accuracy and decrease disparity between planned and final implant position.

CT-to-fluoroscopy registration versus scan-and-plan registration for robot-assisted insertion of lumbar pedicle screws

OBJECTIVE

Pedicle screw insertion for stabilization after lumbar fusion surgery is commonly performed by spine surgeons. With the advent of navigation technology, the accuracy of pedicle screw insertion has increased. Robotic guidance has revolutionized the placement of pedicle screws with 2 distinct radiographic registration methods, the scan-and-plan method and CT-to-fluoroscopy method. In this study, the authors aimed to compare the accuracy and safety of these methods.

METHODS

A retrospective chart review was conducted at 2 centers to obtain operative data for consecutive patients who underwent robot-assisted lumbar pedicle screw placement. The newest robotic platform (Mazor X Robotic System) was used in all cases. One center used the scan-and-plan registration method, and the other used CT-to-fluoroscopy for registration. Screw accuracy was determined by applying the Gertzbein-Robbins scale. Fluoroscopic exposure times were collected from radiology reports.

RESULTS

Overall, 268 patients underwent pedicle screw insertion, 126 patients with scan-and-plan registration and 142 with CT-to-fluoroscopy registration. In the scan-and-plan cohort, 450 screws were inserted across 266 spinal levels (mean 1.7 ± 1.1 screws/level), with 446 (99.1%) screws classified as Gertzbein-Robbins grade A (within the pedicle) and 4 (0.9%) as grade B (< 2-mm deviation). In the CT-to-fluoroscopy cohort, 574 screws were inserted across 280 lumbar spinal levels (mean 2.05 ± 1.7 screws/ level), with 563 (98.1%) grade A screws and 11 (1.9%) grade B (p = 0.17). The scan-and-plan cohort had nonsignificantly less fluoroscopic exposure per screw than the CT-to-fluoroscopy cohort (12 ± 13 seconds vs 11.1 ± 7 seconds, p = 0.3).

CONCLUSIONS

Both scan-and-plan registration and CT-to-fluoroscopy registration methods were safe, accurate, and had similar fluoroscopy time exposure overall.

Freehand Pedicle Screw Insertion in Spondylitis Tuberculosis Kyphosis Correction Using Cantilever Method: A Breach Rate Analysis of 168 Consecutive Screws

Background

The cantilever method is a standard for two-dimensional deformity correction, as in spondylitis tuberculosis kyphotic deformity. An accurate and secured pedicle screw placement as part of the correction tools is essential to accommodate reduction while preventing screw-related complications. Many literatures have described the pedicle screw misplacement in cases with “normal” bone quality (ie, scoliosis, Scheuermann’s kyphosis, ankylosing spondylitis, trauma) or in the obviously abnormal bone such as osteoporosis. However, to our knowledge, the pedicle screw accuracy in cases of deformity correction of tuberculous kyphosis was not previously reported.

Methods

This is a retrospective study of 168 pedicle screws in 14 consecutive cases of spondylitis tuberculosis with kyphotic deformity. The cantilever reduction method with freehand screw insertion technique was done in all cases to correct the deformity. Postoperative computed tomography (CT) evaluation was done to evaluate screw position and breach rates.

Results

Among the 168 screws, accurate pedicle screw placement was accomplished in 39.3% screws (Gertzbein–Robbins Grade A). The overall breach rate was 61.9%, which was most commonly occurred on the segment proximal to the apex of the deformity (p=0.001). The lateral breach was more common than the medial breach (52.3% vs 7.7%). The pedicle screw on the thoracal region has a greater breach incidence than those on the lumbar region especially those on T9, T10, and T11. There was no injury to the surrounding neurovascular and pleural structures. No revision surgeries were required.

Conclusion

Freehand pedicle screw insertion in spondylitis tuberculosis kyphotic reduction has proved to be safe. However, the accuracy should be improved to prevent long-term screw-related complications.

10-Year Trends in the Surgical Management of Patients with Spinal Metastases: A Scoping Review

BACKGROUND

Spinal metastases are present in approximately 20% of patients with cancer, giving a risk for neurologic dysfunction and instability. In already frail patients, surgeons strive to improve quality of life. Our goal was to review a 10-year trend in the surgical management of spinal metastases.

METHODS

A scoping review was performed systematically using PubMed to assess trends in surgical treatment for spinal metastases. The search terms used were: metastas∗, "neoplasm metastasis"[Mesh], "Spine"[Mesh], spine, spinal, "vertebral column," "vertebral body," laser, robot, radiofrequency, screws, fixation, "separation surgery," corpectomy, vertebrectomy, spondylectomy, vertebroplasty, kyphoplasty, surgery, "open surgery," "mini open surgery," "minimally invasive surgery," endoscopy, thoracoscopy, corpectom∗, vertebrectom∗, spondylectom∗, "en bloc," and MIS. The variables of interest were neurologic improvement, tumor recurrence, reoperation, and overall survival.

RESULTS

A total of 2132 articles were found within the primary query. Fifty-six studies were selected for final review. The results were organized into main surgical practices: decompression, mechanical stabilization, and pain management. For separation surgery, clinical outcomes were overall 1-year survival, 40.7%-78.4%; recurrence rate, 4.3%-22%; reoperation, 5%; and complications, 5.4%-14%. For corpectomy, clinical outcomes were overall 1-year survival, 30%-92%; reoperation, 1.1%-50%; and recurrence rate, of 1.1%-28%. Complications and reoperations with spinal instrumentation were 0%-13.6% and 0%-15%, respectively. Cement augmentation achieved pain reduction rates of 56%-100%, neurologic improvement/stability 84%-100%, and complication rates 6%-56%. Laser achieved local tumor control rate of 71%-82% at 1 year follow-up, reoperation rate of 15%-31%, and complication rate of 5%-26%.

CONCLUSIONS

Minimally invasive techniques for decompression and stabilization seem to be the preferred method to surgically treat metastatic spine disease, with good outcomes. More research with high level of evidence is required to support the long-term outcomes of these approaches.

Does robot-assisted navigation influence pedicle screw selection and accuracy in minimally invasive spine surgery?

OBJECTIVE

The accuracy of percutaneous pedicle screw placement has increased with the advent of robotic and surgical navigation technologies. However, the effect of robotic intraoperative screw size and trajectory templating remains unclear. The purpose of this study was to compare pedicle screw sizes and accuracy of placement using robotic navigation (RN) versus skin-based intraoperative navigation (ION) alone in minimally invasive lumbar fusion procedures.

METHODS

A retrospective cohort study was conducted using a single-institution registry of spine procedures performed over a 4-year period. Patients who underwent 1- or 2-level primary or revision minimally invasive surgery (MIS)–transforaminal lumbar interbody fusion (TLIF) with pedicle screw placement, via either robotic assistance or surgical navigation alone, were included. Demographic, surgical, and radiographic data were collected. Pedicle screw type, quantity, length, diameter, and the presence of endplate breach or facet joint violation were assessed. Statistical analysis using the Student t-test and chi-square test was performed to evaluate the differences in pedicle screw sizes and the accuracy of placement between both groups.

RESULTS

Overall, 222 patients were included, of whom 92 underwent RN and 130 underwent ION MIS-TLIF. A total of 403 and 534 pedicle screws were placed with RN and ION, respectively. The mean screw diameters were 7.25 ± 0.81 mm and 6.72 ± 0.49 mm (p < 0.001) for the RN and ION groups, respectively. The mean screw length was 48.4 ± 4.48 mm in the RN group and 45.6 ± 3.46 mm in the ION group (p < 0.001). The rates of “ideal” pedicle screws in the RN and ION groups were comparable at 88.5% and 88.4% (p = 0.969), respectively. The overall screw placement was also similar. The RN cohort had 63.7% screws rated as good and 31.4% as acceptable, while 66.1% of ION-placed screws had good placement and 28.7% had acceptable placement (p = 0.661 and p = 0.595, respectively). There was a significant reduction in high-grade breaches in the RN group (0%, n = 0) compared with the ION group (1.2%, n = 17, p = 0.05).

CONCLUSIONS

The results of this study suggest that robotic assistance allows for placement of screws with greater screw diameter and length compared with surgical navigation alone, although with similarly high accuracy. These findings have implied that robotic platforms may allow for safe placement of the “optimal screw,” maximizing construct stability and, thus, the ability to obtain a successful fusion.

Accuracy of Robot-Assisted Percutaneous Pedicle Screw Placement under Regional Anesthesia: A Retrospective Cohort Study

Background

Robot-assisted pedicle screw placement is usually performed under general anesthesia to keep the body still. The aim of this study was to compare the accuracy of the robot-assisted technique under regional anesthesia with that of conventional fluoroscopy-guided percutaneous pedicle screw placement under general anesthesia in minimally invasive lumbar fusion surgery.

Methods

This study recruited patients who underwent robot-assisted percutaneous endoscopic lumbar interbody fusion (PELIF) or fluoroscopy-guided minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) between December 2017 and February 2020 at a single center. Based on the method of percutaneous pedicle screw placement used, patients were divided into the robot-assisted under regional anesthesia (group RE-RO) and fluoroscopy-guided under general anesthesia (group GE-FLU) groups. The primary outcome measures were screw accuracy and the incidence of facet joint violation (FJV). Secondary outcome measures included X-ray and visual analogue scale (VAS) scores which were used to evaluate the degree of the postoperative pain at 4 hours and on postoperative days 1, 2, and 3. Intraoperative adverse events were also recorded.

Results

Eighteen patients were included in group RE-RO, and 23 patients were included in group GE-FLU. The percentages of clinically acceptable screws (Gertzbein and Robbins grades A and B) were 94.4% and 91.5%, respectively. There was no significant difference in the percentages of clinically acceptable screws (p=0.44) or overall Gertzbein and Robbins screw accuracy grades (p=0.35). Only the top screws were included in the analysis of FJVs. The percentages of FJV (Babu grades 1, 2, and 3) were 5.6% and 28.3%, respectively. This difference was statistically significant (p=0.01). Overall, the FJV grades in group RE-RO were significantly better than those in group GE-FLU (p=0.009). The mean fluoroscopy time for each screw in group RE-RO was significantly shorter than that in group GE-FLU (group RE-RO: 5.4 ± 1.9 seconds and group GE-FLU: 6.8 ± 2.0 seconds; p=0.03). The postoperative pain between the RE-RO and GE-FLU groups was not statistically significant. The intraoperative adverse events included 1 case of registration failure and 1 case of guide-wire dislodgment in group RE-RO, as well as 2 cases of screw misplacement in group GE-FLU. No complications related to anesthesia were observed.

Conclusion

Robot-assisted pedicle screw placement under regional anesthesia can be performed effectively and safely. The accuracy is comparable to the conventional technique. Moreover, this technique has the advantage of fewer FJVs and a lower radiation time.

Initial Intraoperative Experience with Robotic-Assisted Pedicle Screw Placement with Cirq® Robotic Alignment: An Evaluation of the First 70 Screws

BACKGROUND

Robot-guided spine surgery is based on a preoperatively planned trajectory that is reproduced in the operating room by the robotic device. This study presents our initial experience with thoracolumbar pedicle screw placement using Brainlab's Cirq^® surgeon-controlled robotic arm (BrainLab, Munich, Germany).

METHODS

All patients who underwent robotic-assisted implantation of pedicle screws in the thoracolumbar spine were included in the study. Our workflow, consisting of preoperative imagining, screw planning, intraoperative imaging with automatic registration, fusion of the preoperative and intraoperative imaging with a review of the preplanned screw trajectories, robotic-assisted insertion of K-wires, followed by a fluoroscopy-assisted insertion of pedicle screws and control iCT scan, is described.

RESULTS

A total of 12 patients (5 male and 7 females, mean age 67.4 years) underwent 13 surgeries using the Cirq^® Robotic Alignment Module for thoracolumbar pedicle screw implantation. Spondylodiscitis, metastases, osteoporotic fracture, and spinal canal stenosis were detected. A total of 70 screws were implanted. The mean time per screw was 08:27 ± 06:54 min. The mean time per screw for the first 7 surgeries (first 36 screws) was 16:03 ± 09:32 min and for the latter 6 surgeries (34 screws) the mean time per screw was 04:35 ± 02:11 min (p < 0.05). Mean entry point deviation was 1.9 ± 1.23 mm, mean deviation from the tip of the screw was 2.61 ± 1.6 mm and mean angular deviation was 3.5° ± 2°. For screw-placement accuracy we used the CT-based Gertzbein and Robbins System (GRS). Of the total screws, 65 screws were GRS A screws (92.85%), one screw was a GRS B screw, and two further screws were grade C. Two screws were D screws (2.85%) and underwent intraoperative revision. There were no perioperative deficits.

CONCLUSION

Brainlab's Cirq^® Robotic Alignment surgeon-controlled robotic arm is a safe and beneficial method for accurate thoracolumbar pedicle screw placement with high accuracy.

Robotic navigation in spine surgery: Where are we now and where are we going?

Robotic navigation is a new and rapidly emerging niche within minimally invasive spine surgery. The robotic arms-race began in 2004 and has resulted in no less than four major robotic surgical adjuncts. Current Food and Drug Administration (FDA)-approved applications of robotic navigation are limited to pedicle screw instrumentation, but new indications and experimental applications are rapidly emerging. As with any new technology, robotic navigation must be vetted for clinical efficacy, efficiency, safety, and cost-effectiveness. Given the rapid advancements made on a yearly basis, it is important to make frequent and objective assessments of the available technology. Thus, the authors seek to provide the most up-to-date review of the history, currently available technology, learning curve, novel applications, and cost effectiveness of today's available robotic systems as it relates to spine surgery.

Complications and Revision Rates in Minimally Invasive Robotic-Guided Versus Fluoroscopic-Guided Spinal Fusions: The MIS ReFRESH Prospective Comparative Study

STUDY DESIGN

Prospective, multicenter, partially randomized.

OBJECTIVE

Assess rates of complications, revision surgery, and radiation between Mazor robotic-guidance (RG) and fluoro-guidance (FG).

SUMMARY OF BACKGROUND DATA

Minimally invasive surgery MIS ReFRESH is the first study designed to compare RG and FG techniques in adult minimally invasive surgery (MIS) lumbar fusions.

METHODS

Primary endpoints were analyzed at 1 year follow-up. Analysis of variables through Cox logistic regression and a Kaplan-Meier Survival Curve of surgical complications.

RESULTS

Nine sites enrolled 485 patients: 374 (RG arm) and 111 (FG arm). 93.2% of patients had more than 1 year f/u. There were no differences for sex, Charlson Comorbidity Index, diabetes, or tumor. Mean age of RG patients was 59.0 versus 62.5 for FG (P = 0.009) and body mass index (BMI) was 31.2 versus 28.1 (P< 0.001). Percentage of smokers was almost double in the RG (15.2% vs. 7.2%, P = 0.029). Surgical time was similar (skin-to-skin time/no. of screws) at 24.9 minutes RG and 22.9 FG (P = 0.550). Fluoroscopy during surgery/no. of screws was 15.5 seconds RG versus 35.4 seconds FG, (15 seconds average reduction). Fluoroscopy time during instrumentation/no. of screws was 3.6 seconds RG versus 17.8 seconds FG showing an 80% average reduction of fluoro time/screw in RG (P < 0.001). Within 1 year follow-up, there were 39 (10.4%) surgical complications RG versus 39 (35.1%) FG, and 8 (2.1%) revisions RG versus 7 (6.3%) FG. Cox regression analysis including age, sex, BMI, CCI, and no. of screws, demonstrated that the hazard ratio (HR) for complication was 5.8 times higher FG versus RG (95% CI: 3.5-9.6, P < 0.001). HR for revision surgery was 11.0 times higher FG versus RG cases (95% CI 2.9-41.2, P < 0.001).

CONCLUSION

Mazor robotic-guidance was found to have a 5.8 times lower risk of a surgical complication and 11.0 times lower risk for revision surgery. Surgical time was similar between groups and robotic-guidance reduced fluoro time per screw by 80% (approximately 1 min/case).Level of Evidence: 2.

Minimally Invasive Surgery for Spinal Metastasis: A Review

OBJECTIVE

Minimally invasive surgery (MIS) techniques have advanced the treatment of metastatic diseases to the spine. The objective of this review is to describe clinical outcomes, benefits, and complications of these techniques.

METHODS

All relevant clinical studies describing the role of MIS, computer-assisted navigation (CAN), robot-assisted (RA) procedures, and laser interstitial thermal therapy (LITT) in the treatment of metastatic spine diseases were identified from PubMed, MEDLINE, and relevant article bibliographies.

RESULTS

For MIS articles, we filtered 1480 results and identified 26 studies. For CAN, we searched 464 articles to identify 18 articles for review. For RA, we searched 321 results to identify 7 studies for review. For LITT, we identified 21 articles for review.

CONCLUSIONS

MIS for the treatment of spine metastasis has significant potential benefits in reducing surgical site infections, hospital stay, and blood loss without compromising instrument accuracy or overall outcomes. Overall, MIS and its adjuncts have the potential to reduce the risks involved in the treatment of patients with metastatic disease to the spinal column without compromising the benefits of decompression and stabilization of the spine.