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

Comparative evaluation of postoperative outcomes and expenditure between robotic and conventional single-level lumbar fusion surgery: a comprehensive analysis of nationwide inpatient sample data

INTRODUCTION

In this study, we investigate the evolution of lumbar fusion surgery with robotic assistance, specifically focusing on the impact of robotic technology on pedicle screw placement and fixation. Utilizing data from the Nationwide Inpatient Sample (NIS) covering 2016 to 2019, we conduct a comprehensive analysis of postoperative outcomes and costs for single-level lumbar fusion surgery. Traditionally, freehand techniques for pedicle screw placement posed risks, leading to the development of robotic-assisted techniques with advantages such as reduced misplacement, increased precision, smaller incisions, and decreased surgeon fatigue. However, conflicting study results regarding the efficacy of robotic assistance in comparison to conventional techniques have prompted the need for a thorough evaluation. With a dataset of 461,965 patients, our aim is to provide insights into the impact of robotic assistance on patient care and healthcare resource utilization. Our primary goal is to contribute to the ongoing discourse on the efficacy of robotic technology in lumbar fusion procedures, offering meaningful insights for optimizing patient-centered care and healthcare resource allocation.

METHODS

This study employed data from the Nationwide Inpatient Sample (NIS) spanning the years 2016 to 2019 from USA, 461,965 patients underwent one-level lumbar fusion surgery, with 5770 of them having the surgery with the assistance of robotic technology. The study focused primarily on one-level lumbar fusion surgery and excluded non-elective cases and those with prior surgeries. The analysis encompassed the identification of comorbidities, surgical etiologies, and complications using specific ICD-10 codes. Throughout the study, a constant comparison was made between robotic and non-robotic lumbar fusion procedures. Various statistical methods were applied, with a p value threshold of < 0.05, to determine statistical significance.

RESULTS

Robotic-assisted lumbar fusion surgeries demonstrated a significant increase from 2016 to 2019, comprising 1.25% of cases. Both groups exhibited similar patient demographics, with minor differences in payment methods, favoring Medicare in non-robotic surgery and more private payer usage in robotic surgery. A comparison of comorbid conditions revealed differences in the prevalence of hypertension, dyslipidemia, and sleep apnea diagnoses-In terms of hospitalization outcomes and costs, there was a slight shorter hospital stay of 3.06 days, compared to 3.13 days in non-robotic surgery, showcasing a statistically significant difference (p = 0.042). Robotic surgery has higher charges, with a mean charge of $154,673, whereas non-robotic surgery had a mean charge of $125,467 (p < 0.0001). Robotic surgery demonstrated lower rates of heart failure, acute coronary artery disease, pulmonary edema, venous thromboembolism, and traumatic spinal injury compared to non-robotic surgery, with statistically significant differences (p < 0.05). Conversely, robotic surgery demonstrated increased post-surgery anemia and blood transfusion requirements compared to non-robotic patients (p < 0.0001). Renal disease prevalence was similar before surgery, but acute kidney injury was slightly higher in the robotic group post-surgery (p = 0.038).

CONCLUSION

This is the first big data study on this matter, our study showed that Robotic-assisted lumbar fusion surgery has fewer post-operative complications such as heart failure, acute coronary artery disease, pulmonary edema, venous thromboembolism, and traumatic spinal injury in comparison to conventional methods. Conversely, robotic surgery demonstrated increased post-surgery anemia, blood transfusion and acute kidney injury. Robotic surgery has higher charges compared to non-robotic surgery.

Robotic-assisted spine surgery-a narrative review

Background and Objective

Emerging technologies have increasingly been adopted in spine surgery in the attempt to increase precision and improve outcomes. Robotic assistance is an area of significant interest, with proposed benefits including increased accuracy, decreased complication rates, and decreased radiation exposure. The purpose of this review is to provide an overview of the currently available robotic assistance systems and their associated outcomes and limitations.

Methods

A review of national databases was performed using key terms "robotic", "spine", and "surgery" for literature from 2014 to 2023. Studies that aimed to describe the utilities of endoscopic surgeries, associated outcomes, limitations, and future directions were included. Studies that were not in English were excluded.

Key Content and Findings

This review includes a brief overview of the history of robotic spine surgery as well as its clinical outcomes, limitations, and future directions.

Conclusions

Robotic-assisted spine surgery has seen increasing use in the attempt to increase precision and improve outcomes and has been associated with increased accuracy in pedicle screw placement and decreased complication rates. Barriers to its adoption include a significant learning curve, possibly longer operative cases, and significant associated costs. As robotic assistance continues to become increasingly popular in spine surgery, it is critical for surgeons to understand the technology available and the associated outcomes to make informed decisions when considering which system to incorporate into their practice.

Pedicle Screw-Associated Violation of the Adjacent Unfused Facet Joint: Clinical Outcomes and Fusion Rates

STUDY DESIGN

Retrospective review of a prospective randomized trial.

OBJECTIVES

To compare outcome scores and fusion rates in patients with and without pedicle screw-associated facet joint violation (FJV) after a single-level lumbar fusion.

METHODS

Clinical outcomes data and computed tomography (CT) imaging were reviewed for 157 patients participating in a multicenter prospective trial. Post-operative CT scans at 12-months follow-up were examined for fusion status and FJV. Patient-reported outcomes (PROs) included Oswestry Disability Index (ODI) and Visual Analog Scale (VAS) for leg and low back pain. Chi-square test of independence was used to compare proportions between groups on categorical measures. Two-sample t-test was used to identify differences in mean patient outcome scores. Logistic regression models were performed to determine association between FJV and fusion rates.

RESULTS

Of the 157 patients included, there were 18 (11.5%) with FJV (Group A) and 139 (88.5%) without FJV (Group B). Patients with FJV experienced less improvement in ODI (P = .004) and VAS back pain scores (P = .04) vs patients without FJV. There was no difference in mean VAS leg pain (P = .4997). The rate of fusion at 12-months for patients with FJV (27.8%) was lower compared to those without FJV (71.2%) (P = .0002). Patients with FJV were 76% less likely to have a successful fusion at 12-months.

CONCLUSION

Pedicle screw-associated violation of the adjacent unfused facet joint during single-level lumbar fusion is associated with less improvement in back pain, back pain-associated disability, and a lower fusion rate at 1-year after surgery.

Advancements in Robotic-Assisted Spine Surgery

Applications and workflows around spinal robotics have evolved since these systems were first introduced in 2004. Initially approved for lumbar pedicle screw placement, the scope of robotics has expanded to instrumentation across different regions. Additionally, precise navigation can aid in tumor resection or spinal lesion ablation. Robot-assisted surgery can improve accuracy while decreasing radiation exposure, length of hospital stay, complication, and revision rates. Disadvantages include increased operative time, dependence on preoperative imaging among others. The future of robotic spine surgery includes automated surgery, telerobotic surgery, and the inclusion of machine learning or artificial intelligence in preoperative planning.

Robot-assisted Temporary Hemiepiphysiodesis With Eight-plates for Lower Extremity Deformities in Children

PURPOSE

This study was performed to compare the radiographic results of robot-assisted and traditional methods of treating lower extremity deformities (LEDs).

METHODS

From January 2019 to February 2022, 55 patients with LEDs were treated by temporary hemiepiphysiodesis with eight-plates. They were divided into a robot group and a freehand group. The fluoroscopy time and operation time were recorded. The accuracy of screw placement was measured after the operation using the following parameters: coronal entering point (CEP), sagittal entering point (SEP), and angle between the screw and epiphyseal plate (ASEP). The limb length discrepancy (LLD) and femorotibial angle (FTA) were measured before the operation, after the operation, and at the last follow-up. Patients were followed up for 12 to 24 months, and the radiographic results of the 2 groups were compared.

RESULTS

Among the 55 patients with LEDs, 36 had LLD and 19 had angular deformities. Seventy-six screws were placed in the robot group and 85 in the freehand group. There was no difference in the CEP between the 2 groups ( P >0.05). The robot group had a better SEP (2.96±1.60 vs. 6.47±2.80 mm) and ASEP (3.46°±1.58° vs. 6.92°±3.92°) than the freehand group ( P <0.001). At the last follow-up, there was no difference in the LLD or FTA improvement between the two groups ( P >0.05). The incidence of complications was significantly lower in the robot group than in the freehand group (0/27 vs. 5/28, P <0.05).

CONCLUSION

Robot-assisted temporary hemiepiphysiodesis with eight-plates is a safe and effective method for treating LEDs in children. Robotic placement of screws is superior to freehand placement with respect to the entering position and direction. Although the correction effect for LLD and angular deformity is similar, screw dislocation is less common when using robot assistance.

LEVELS OF EVIDENCE

Level-III. Retrospective comparative study.

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.

Top 25 Most-Cited Articles on Robotic-Assisted Lumbar Spine Surgery

BACKGROUND

Robot-guided lumbar spine surgery has evolved rapidly with evidence to support its utility and feasibility compared with conventional freehand and fluoroscopy-based techniques. The objective of this study was to assess trends among the top 25 most-cited articles pertaining to robotic-guided lumbar spine surgery.

METHODS

An "advanced document search" using Boolean search operator terms was performed on 16 November 2022 through the Web of Science and SCOPUS citation databases to determine the top 25 most-referenced articles on robotic lumbar spine surgery. The articles were compiled into a directory and hierarchically organized based on the total number of citations.

RESULTS

Cumulatively, the "Top 25" list for robot-assisted navigation in lumbar spine surgery received 2240 citations, averaging 97.39 citations annually. The number of citations ranged from 221 to 40 for the 25 most-cited articles. The most-cited study, by Kantelhardt et al, received 221 citations, averaging 18 citations per year.

CONCLUSIONS

As utilization of robot-guided modalities in lumbar spine surgery increases, this review highlights the most impactful studies to support its efficacy and implementation. Practical considerations such as cost-effectiveness, however, need to be better defined through further longitudinal studies that evaluate patient-reported outcomes and cost-utility.

CLINICAL RELEVANCE

Through an overview of the top 25 most-cited articles, the present review highlights the rising prominence and technical efficacy of robotic-guided systems within lumbar spine surgery, with consideration to pragmatic limitations and need for additional data to facilitate cost-effective applications.

LEVEL OF EVIDENCE: 5

Pedicle screw placement accuracy in robot-assisted versus image-guided freehand surgery of thoraco-lumbar spine (ROBARTHRODESE): study protocol for a single-centre randomized controlled trial

BACKGROUND

Robotic spinal surgery may result in better pedicle screw placement accuracy, and reduction in radiation exposure and length of stay, compared to freehand surgery. The purpose of this randomized controlled trial (RCT) is to compare screw placement accuracy of robot-assisted surgery with integrated 3D computer-assisted navigation versus freehand surgery with 2D fluoroscopy for arthrodesis of the thoraco-lumbar spine.

METHODS

This is a single-centre evaluator-blinded RCT with a 1:1 allocation ratio. Participants (n = 300) will be randomized into two groups, robot-assisted (Mazor X Stealth Edition) versus freehand, after stratification based on the planned number of pedicle screws needed for surgery. The primary outcome is the proportion of pedicle screws placed with grade A accuracy (Gertzbein-Robbins classification) on postoperative computed tomography images. The secondary outcomes are intervention time, operation room occupancy time, length of stay, estimated blood loss, surgeon's radiation exposure, screw fracture/loosening, superior-level facet joint violation, complication rate, reoperation rate on the same level or one level above, functional and clinical outcomes (Oswestry Disability Index, pain, Hospital Anxiety and Depression Scale, sensory and motor status) and cost-utility analysis.

DISCUSSION

This RCT will provide insight into whether robot-assisted surgery with the newest generation spinal robot yields better pedicle screw placement accuracy than freehand surgery. Potential benefits of robot-assisted surgery include lower complication and revision rates, shorter length of stay, lower radiation exposure and reduction of economic cost of the overall care.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05553028. Registered on September 23, 2022.

Perception of Robotics and Navigation by Spine Fellows and Early Attendings: The Impact of These Technologies on Their Training and Practice

BACKGROUND

There is scant data on the role that robotics and navigation play in spine surgery training and practice of early attendings. This study aimed to assess the impact of navigation and robotics on spine surgery training and practice.

METHODS

A survey gathering information on utilization of navigation and robotics in training and practice was administered to trainees and early attendings.

RESULTS

A total of 51 surveys were returned completed: 71% were attendings (average practice years: 2), 29% were trainees. During training, 22% were exposed to only fluoroscopy, 75% were exposed to navigation, 51% were exposed to robotics, and 40% were exposed to both navigation and robotics. In our sample, 87% and 61% of respondents who had exposure to navigation and robotics, respectively, felt that it had a positive impact on their training. In practice, 28% utilized only fluoroscopy, 69% utilized navigation, 30% utilized robotics, and 28% utilized both navigation and robotics. The top 3 reasons behind positive impact on training and practice were: 1) increased screw accuracy, 2) exposure to upcoming technology, and 3) less radiation exposure. The top 3 reasons behind negative impact were: 1) compromises training to independently place screws, 2) time and personnel requirements, and 3) concerns about availing it in practice. In sum, 76% of attendings felt that they will be utilizing more navigation and robotics in 5 years' time.

CONCLUSIONS

Navigation and robotics have a perceivably positive impact on training and are increasingly being incorporated into practice. However, associated concerns demand spine surgeons to be thoughtful about how they integrate these technologies moving forward.

Robot-navigated pedicle screw insertion can reduce intraoperative blood loss and length of hospital stay: analysis of 1,633 patients utilizing propensity score matching

BACKGROUND CONTEXT

Navigation and robotic technologies have emerged as an alternative option to conventional freehand techniques for pedicle screw insertion. However, the effectiveness of these technologies in reducing the perioperative complications of spinal fusion surgery remains limited due to the small cohort size in the existing literature.

PURPOSE

To investigate whether utilization of robotically navigated pedicle screw insertion can reduce the perioperative complications of spinal fusion surgery-including reoperations-with a sizeable cohort.

STUDY DESIGN

Retrospective study.

PATIENT SAMPLE

Patients who underwent primary lumbar fusion surgery between 2019 and 2022.

OUTCOME MEASURES

Perioperative complications including readmission, reoperation, its reasons, estimated blood loss, operative time, and length of hospital stay.

METHODS

Patients' data were collected including age, sex, race, body mass index, upper-instrumented vertebra, lower-instrumented vertebra, number of screws inserted, and primary procedure name. Patients were classified into the following two groups: freehand group and robot group. The variable-ratio greedy matching was utilized to create the matched cohorts by propensity score and compared the outcomes between the two group.

RESULTS

A total of 1,633 patients who underwent primary instrumented spinal lumbar fusion surgery were initially identified (freehand 1,286; robot 347). After variable ratio matching was performed with age, sex, body mass index, fused levels, and upper instrumented vertebrae level, 694 patients in the freehand group and 347 patients in robot groups were selected. The robot group showed less estimated blood loss (418.9±398.9 vs 199.2±239.6 ml; p<.001), shorter LOS (4.1±3.1 vs 3.2±3.0 days; p<.001) and similar operative time (212.5 vs 222.0 minutes; p=.151). Otherwise, there was no significant difference in readmission rate (3.6% vs 2.6%; p=.498), reoperation rate (3.2% vs 2.6%; p=.498), and screw malposition requiring reoperation (five cases, 0.7% vs one case, 0.3%; p=1.000).

CONCLUSIONS

Perioperative complications requiring readmission and reoperation were similar between fluoroscopy guided freehand and robotic surgery. Robot-guided pedicle screw insertion can enhance surgical efficiency by reducing intraoperative blood loss and length of hospital stay without extending operative time.

The impact of robotic assistance for lumbar fusion surgery on 90-day surgical outcomes and 1-year revisions

Objectives

To evaluate the (1) 90-day surgical outcomes and (2) 1-year revision rate of robotic versus nonrobotic lumbar fusion surgery.

Methods

Patients >18 years of age who underwent primary lumbar fusion surgery at our institution were identified and propensity-matched in a 1:1 fashion based on robotic assistance during surgery. Patient demographics, surgical characteristics, and surgical outcomes, including 90-day surgical complications and 1-year revisions, were collected. Multivariable regression analysis was performed. Significance was set to P < 0.05.

Results

Four hundred and fifteen patients were identified as having robotic lumbar fusion and were matched to a control group. Bivariant analysis revealed no significant difference in total 90-day surgical complications (P = 0.193) or 1-year revisions (P = 0.178). The operative duration was longer in robotic surgery (287 + 123 vs. 205 + 88.3, P ≤ 0.001). Multivariable analysis revealed that robotic fusion was not a significant predictor of 90-day surgical complications (odds ratio [OR] = 0.76 [0.32-1.67], P = 0.499) or 1-year revisions (OR = 0.58 [0.28-1.18], P = 0.142). Other variables identified as the positive predictors of 1-year revisions included levels fused (OR = 1.26 [1.08-1.48], P = 0.004) and current smokers (OR = 3.51 [1.46-8.15], P = 0.004).

Conclusion

Our study suggests that robotic-assisted and nonrobotic-assisted lumbar fusions are associated with a similar risk of 90-day surgical complications and 1-year revision rates; however, robotic surgery does increase time under anesthesia.

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.

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.

Technological Advances in Spine Surgery: Navigation, Robotics, and Augmented Reality

Accurate screw placement is critical to avoid vascular or neurologic complications during spine surgery and to maximize fixation for fusion and deformity correction. Computer-assisted navigation, robotic-guided spine surgery, and augmented reality surgical navigation are currently available technologies that have been developed to improve screw placement accuracy. The advent of multiple generations of new technologies within the past 3 decades has presented surgeons with a diverse array of choices when it comes to pedicle screw placement. Considerations for patient safety and optimal outcomes must be paramount when selecting a technology.

Intraoperative CT for Lumbar Fusion Is Not Associated with Improved Short- or Long-Term Complication Profiles

BACKGROUND CONTEXT

The use of intraoperative CT has continued to grow in recent years, as various techniques leverage the promise of improved instrumentation accuracy and the hope for decreased complications. Nonetheless, the literature regarding the short- and long-term complications associated with such techniques remains scant and/or confounded by indication and selection bias.

PURPOSE

To use causal inference techniques to determine whether intraoperative CT use is associated with an improved complication profile as compared to conventional radiography for single-level lumbar fusions, an increasingly commonplace application for this technology.

STUDY DESIGN/SETTING

Inverse probability weighted retrospective cohort study carried out within a large integrated healthcare network PATIENT SAMPLE: Adult patients who underwent surgical treatment of spondylolisthesis via lumbar fusion from January 2016 through December 2021 OUTCOME MEASURES: Our primary outcome was the incidence rate of revision surgery. Our secondary outcome was the incidence of composite 90-day complications (deep and superficial surgical site infection, venous thromboembolic events, and unplanned readmissions).

METHODS

Demographics, intraoperative information, and postoperative complications were abstracted from electronic health records. A propensity score was developed utilizing a parsimonious model to account for covariate interaction with our primary predictor, intraoperative imaging technique. This propensity score was utilized in the creation of inverse probability weights to adjust for indication and selection bias. The rate of revisions within 3 years as well as the rate of revisions at any time-point were compared between cohorts using Cox regression analysis. The incidence of composite 90-day complications were compared using negative binomial regression.

RESULTS

Our patient population consisted of 583 patients, with 132 who underwent intraoperative CT and 451 who underwent conventional radiographic techniques. There were no significant differences between cohorts following inverse probability weighting. No significant differences were detected in 3-year revision rates (HR 0.74 [95% CI 0.29, 1.92]; p=0.5), overall revision rates (HR 0.54 [95% CI 0.20, 1.46]; p=0.2), or 90-day complications (RC -0.24 [95% CI -1.35, 0.87]; p=0.7).

CONCLUSIONS

Intraoperative CT use was not associated with an improved complication profile in either the short- or long-term for patients undergoing single-level instrumented fusion. This observed clinical equipoise should be weighed against resource and radiation-related costs when considering intraoperative CT for low complexity fusions.

Robotics in spine surgery: systematic review of literature

PURPOSE

Over 4.83 million spine surgery procedures are performed annually around the world. With the considerable caseload and the precision needed to achieve optimal spinal instrumentation, technical progress has helped to improve the technique's safety and accuracy with the development of peri-operative assistance tools. Contrary to other surgical applications already part of the standard of care, the development of robotics in spine surgery is still a novelty and is not widely available nor used. Robotics, especially when coupled with other guidance modalities such as navigation, seems to be a promising tool in our quest for accuracy, improving patient outcomes and reducing surgical complications. Robotics in spine surgery may also be for the surgeon a way to progress in terms of ergonomics, but also to respond to a growing concern among surgical teams to reduce radiation exposure.

METHOD

We present in this recent systematic review of the literature realized according to the PRISMA guidelines the place of robotics in spine surgery, reviewing the comparison to standard techniques, the current and future indications, the learning curve, the impact on radiation exposure, and the cost-effectiveness.

RESULTS

Seventy-six relevant original studies were identified and analyzed for the review.

CONCLUSION

Robotics has proved to be a safe help for spine surgery, both for the patient with a decrease of operating time and increase in pedicular screw accuracy, and for the surgical team with a decrease of radiation exposure. Medico-economic studies demonstrated that despite a high buying cost, the purchase of a robot dedicated for spine surgery is cost-effective resulting in lesser revision, lower infection, reduced length of stay, and shorter surgical procedure.

Feasibility of outpatient robot assisted minimally invasive transforaminal lumbar interbody fusion

Introduction

Lumbar interbody fusion is a common spine procedure. 199,140 elective lumbar fusions were performed in the United States in 2015. Robot assisted (RA) pedicle screw placement has advanced minimally invasive spine surgery (MIS) making short stay transforaminal lumbar interbody fusions (TLIF) with same day or next day discharge a possibility for select patients.

Methods

This study is a retrospective case series of a single surgeon's experience with RA MIS TLIF using the Globus ExcelsiusGPS system. Patients undergoing RA MIS TLIF at an outpatient surgery center between August 2020 and February 2021 were included in the study.

Results

Twenty-three patients met inclusion criteria. Ninety-six RA pedicle screws and 25 interbody cages were placed. 96/96 (100%) pedicle screws and 25/25 (100%) interbodies were found to be in satisfactory position using intraoperative x-ray. None of the instrumentation required re-placement or revision intraoperatively. 20/23 (87%) patients were able to discharge within 24 hours of the procedure. 2/23 (8.7%) patients discharged on the day of surgery. One patient of 23 (4.3%) required discharge to an inpatient rehabilitation facility post operatively. 0/23 (0%) patients required readmission for pain control.

Conclusions

Our study demonstrates the safety and feasibility of outpatient RA MIS TLIF for select patients. Future directions include a larger study to elucidate characteristics of the best candidates for outpatient RA MIS TLIF.

Index Surgery Cost of Fluoroscopic Freehand Versus Robotic-Assisted Pedicle Screw Placement in Lumbar Instrumentation: An Age, Sex, and Approach-Matched Cohort Comparison

BACKGROUND

Spine surgery costs are notoriously high, and there are already criticisms and concerns over the economic effects. There is no consensus on cost variation with robot-assisted spine fusion (rLF) compared with a manual fluoroscopic freehand (fLF) approach. This study looks to compare the early costs between the robotic method and the freehand method in lumbar spine fusion.

METHODS

rLFs by one spine surgeon were age, sex, and approach-matched to fLF procedures by another spine surgeon. Variable direct costs, readmissions, and revision surgeries within 90 days were reviewed and compared.

RESULTS

Thirty-nine rLFs were matched to 39 fLF procedures. No significant differences were observed in clinical outcomes. rLF had higher total encounter costs (P < 0.001) and day-of-surgery costs (P = 0.005). Increased costs were mostly because of increased supply cost (0.0183) and operating room time cost (P < 0.001). Linear regression showed a positive relationship with operating room time and cost in rLF (P < 0.001).

CONCLUSION

rLF is associated with a higher index surgery cost. The main factor driving increased cost is supply costs, with other variables too small in difference to make a notable financial effect. rLF will become more common, and other institutions may need to take a closer financial look at this more novel instrumentation before adoption.

Development and Clinical Trial of a New Orthopedic Surgical Robot for Positioning and Navigation

Robot-assisted orthopedic surgery has great application prospects, and the accuracy of the robot is the key to its overall performance. The aim of this study was to develop a new orthopedic surgical robot to assist in spinal surgeries and to compare its feasibility and accuracy with the existing orthopedic robot. A new type of high-precision orthopedic surgical robot (Tuoshou) was developed. A multicenter, randomized controlled trial was carried out to compare the Tuoshou with the TiRobot (TINAVI Medical Technologies Co., Ltd., Beijing) to evaluate the accuracy and safety of their navigation and positioning. A total of 112 patients were randomized, and 108 patients completed the study. The position deviation of the Kirschner wire placement in the Tuoshou group was smaller than that in the TiRobot group (p = 0.014). The Tuoshou group was better than the TiRobot group in terms of the pedicle screw insertion accuracy (p = 0.016) and entry point deviation (p < 0.001). No differences were observed in endpoint deviation (p = 0.170), axial deviation (p = 0.170), sagittal deviation (p = 0.324), and spatial deviation (p = 0.299). There was no difference in security indicators. The new orthopedic surgical robot was highly accurate and optimized for clinical practice, making it suitable for clinical application.

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.

Robotic Spine Surgery: Past, Present, and Future

STUDY DESIGN

Systematic review.

OBJECTIVE

The aim of this review is to present an overview of robotic spine surgery (RSS) including its history, applications, limitations, and future directions.

SUMMARY OF BACKGROUND DATA

The first RSS platform received United States Food and Drug Administration approval in 2004. Since then, robotic-assisted placement of thoracolumbar pedicle screws has been extensively studied. More recently, expanded applications of RSS have been introduced and evaluated.

METHODS

A systematic search of the Cochrane, OVID-MEDLINE, and PubMed databases was performed for articles relevant to robotic spine surgery. Institutional review board approval was not needed.

RESULTS

The placement of thoracolumbar pedicle screws using RSS is safe and accurate and results in reduced radiation exposure for the surgeon and surgical team. Barriers to utilization exist including learning curve and large capital costs. Additional applications involving minimally invasive techniques, cervical pedicle screws, and deformity correction have emerged.

CONCLUSION

Interest in RSS continues to grow as the applications advance in parallel with image guidance systems and minimally invasive techniques.

IRB APPROVAL

N/A.

Accuracy of Robotic-Assisted Spinal Surgery-Comparison to TJR Robotics, da Vinci Robotics, and Optoelectronic Laboratory Robotics

BACKGROUND

The optoelectronic camera source and data interpolation serve as the foundation for navigational integrity in the robotic-assisted surgical platform. The objective of the current systematic review serves to provide a basis for the numerical disparity that exists when comparing the intrinsic accuracy of optoelectronic cameras: accuracy observed in the laboratory setting versus accuracy in the clinical operative environment. It is postulated that there exists a greater number of connections in the optoelectronic kinematic chain when analyzing the clinical operative environment to the laboratory setting. This increase in data interpolation, coupled with intraoperative workflow challenges, reduces the degree of accuracy based on surgical application and to that observed in controlled musculoskeletal kinematic laboratory investigations.

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 optoelectronic accuracy, registration accuracy, musculoskeletal kinematic platforms, and clinical operative platforms.

RESULTS

A total of 147 references make up 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 of optoelectronic tracking equaled or was less than 0.1 mm of translation and 0.1° of rotation per fiducial. Controlled laboratory platforms reported 0.1 to 0.5 mm of translation and 0.1°-1.0° of rotation per array. There is a huge falloff in clinical applications: accuracy in robotic-assisted spinal surgery reported 1.5 to 6.0 mm of translation and 1.5° to 5.0° of rotation when comparing planned to final implant position. Total Joint Robotics and da Vinci urologic robotics computed accuracy, as predicted, lies between these two extremes-1.02 mm for da Vinci and 2 mm for MAKO.

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 intraoperative workflow have the potential to improve accuracy and decrease disparity between planned and final implant position. The key determining factors limiting navigation resolution accuracy are highlighted by this Cochrane research analysis.

Radiotherapy and Surgical Advances in the Treatment of Metastatic Spine Tumors: A Narrative Review

Spine tumors encompass a wide range of diseases with a commensurately broad spectrum of available treatments, ranging from radiation for spinal metastases to highly invasive en bloc resection for primary vertebral column malignancies. This high variability in treatment approaches stems both from variability in the goals of surgery (e.g., oncologic cure vs. symptom palliation) and from the significant advancements in surgical technologies that have been made over the past 2 decades. Among these advancements are improvements in surgical technique, namely minimally invasive approaches, increased availability of focused radiation modalities (e.g., proton therapy and linear accelerator devices), and new surgical technologies, such as carbon fiber-reinforced polyether ether ketone rods. In addition, several groups have described nonsurgical interventions, such as vertebroplasty and kyphoplasty for spinal instability secondary to pathologic fracture, and lesion ablation with spinal laser interstitial thermoablation, radiofrequency ablation, or cryoablation. We provide an overview of the latest technological advancements in spinal oncology and their potential usefulness for modern spinal oncologists.