Miniature robotic guidance for spine surgery — introduction of a novel system and analysis of challenges encountered during the clinical development phase at two spine centres

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.

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.

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.

Analysing the learning curve of prostate enucleation with the Holmium laser: A retrospective, single-center experience

BACKGROUND

Holmium laser enucleation of the prostate (HoLEP) is a proven surgical technique for the treatment of benign prostatic hyperplasia (BPH). However, its challenging learning curve prevents its widespread adoption by urologists. The aim of this study was to analyse the learning curve of HoLEP and to determine the factors accelerating it.

METHODS

This was a retrospective, monocentric cohort study of the first 60 cases of HoLEP performed by three operators. The primary outcome measure was operative efficiency, defined as the ratio of preoperative prostate volume estimated by trans-abdominal ultrasound (TAUS)to total surgical time in minutes. The studied learning curve parameters included the number of previously performed cases (NPPCs) and monthly case density (CD) (number of monthly performed cases before the studied one).

RESULTS

Overall, 180 patients with a mean age of 71 (±9) years and a mean prostate volume (g) of 80.4 (±41) were included. The mean operative efficiency in the population was 0.74 (±0.37) g/min. Operative efficiency was increased in patients who had been operated on by surgeons with a CD ≥3 (CD ≤2: 0.66 (±0.27) g/min vs. CD ≥3: 0.79 (±0.43) g/min; P=0.012). At 3months, 46 patients (29%) developed stress urinary incontinence (SUI). Early SUI was significantly decreased in patients who had been operated on by surgeons with a CD ≥3 (CD ≤2: 37%, (n=26) vs CD ≥3: 22%, (n=20); P=0.045).

CONCLUSIONS

A high frequency HoLEP procedures, set as one case per week, appeared to accelerate learning curves by improving operative efficiency. A high CD was also associated with reduced rates of early SUI.

LEVEL OF PROOF

5.

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.

R2 advances in robotic-assisted spine surgery: comparative analysis of options, future directions, and bibliometric analysis of the literature

Spine surgery has undergone rapid advancements over the past several decades with the emergence of robotic and minimally invasive surgery (MIS). While conventional MIS spine surgery has had relative success, its complication profile has warranted continued efforts to improve clinical outcomes. We discuss the functional, clinical, and financial aspects of four robotic options for spinal pathologies, namely ROSA, Mazor X, Da Vinci, and ExcelsiusGPS, and conduct a bibliometric analysis to better understand current trends and applications of these robots as the field of robotic spine surgery continues to grow. An extensive search of English-language published literature on robotic-assisted spinal surgery was performed in Elsevier's Scopus database. A bibliometric analysis was then performed on the top 100 most cited papers. The search yielded articles regarding robotic-assisted spine surgery application, limitations, and functional outcomes secondary to spine pathology. Accuracy analyses of 1733 screw placements were reviewed. The top 100 papers were published between 1992 and 2020, with a significant increase from 2015 onwards. The top publishing institution was John Hopkins University (n = 8). The top contributing author was Dr. Isador H. Lieberman (n = 6). The USA (n = 34) had the most articles on robotic spinal surgery, followed by Germany (n = 12). This review examines robotic applications in spine surgery, including four available options: ROSA, Mazor X, Da Vinci, and ExcelsiusGPS. Publication output over time, surgical outcomes, screw accuracy, and cost-effectiveness of these technologies have been investigated here. Certain robots have functional, clinical, and financial differences worth noting. Given the dearth of existing literature reporting postoperative complications and long-term comparative outcomes, there is a clear need for further studies on this matter.

Learning curves in robotic neurosurgery: a systematic review

The transition to performing procedures robotically generally entails a period of adjustment known as a learning curve as the surgeon develops a familiarity with the technology. However, no study has comprehensively examined robotic learning curves across the field of neurosurgery. We conducted a systematic review to characterize the scope of literature on robotic learning curves in neurosurgery, assess operative parameters that may involve a learning curve, and delineate areas for future investigation. PubMed, Embase, and Scopus were searched. Following deduplication, articles were screened by title and abstract for relevance. Remaining articles were screened via full text for final inclusion. Bibliographic and learning curve data were extracted. Of 746 resultant articles, 32 articles describing 3074 patients were included, of which 23 (71.9%) examined spine, 4 (12.5%) pediatric, 4 (12.5%) functional, and 1 (3.1%) general neurosurgery. The parameters assessed for learning curves were heterogeneous. In total, 8 (57.1%) of 14 studies found reduced operative time with increased cases, while the remainder demonstrated no learning curve. Six (60.0%) of 10 studies reported reduced operative time per component with increased cases, while the remainder indicated no learning curve. Radiation time, radiation time per component, robot time, registration time, setup time, and radiation dose were assessed by ≤ 4 studies each, with 0-66.7% of studies demonstrated a learning curve. Four (44.4%) of 9 studies on accuracy showed improvement over time, while the others indicated no improvement over time. The number of cases required to reverse the learning curve ranged from 3 to 75. Learning curves are common in robotic neurosurgery. However, existing studies demonstrate high heterogeneity in assessed parameters and the number of cases that comprise the learning curve. Future studies should seek to develop strategies to reduce the number of cases required to reach the learning curve.

Development of a Robotic Spine Surgery Program: Rationale, Strategy, Challenges, and Monitoring of Outcomes After Implementation

Surgical robots were invented in the 1980s, and since then, robotic-assisted surgery has become commonplace. In the field of spine surgery, robotic assistance is utilized mainly to place pedicle screws, and multiple studies have demonstrated that robots can increase the accuracy of screw placement and reduce radiation exposure to the patient and the surgeon. However, this may be at the cost of longer operative times, complications, and the risk of errors in mapping the patient's anatomy.

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.

A multicenter study of the 5-year trends in robot-assisted spine surgery outcomes and complications

BACKGROUND

Although a growing amount of literature that suggests robots are safe and can achieve comparable outcomes to conventional techniques, much of this literature is limited by small sample sizes and single-surgeon or single center series. Furthermore, it is unclear what the impact of robotic technology has made on operative and clinical outcomes over time. This is the first and largest multicenter study to examine the trends in outcomes and complications after robot-assisted spine surgery over a 5-year period.

METHODS

Adult (≥18 years old) patients who underwent spine surgery with robot-assistance between 2015 and 2019 at four unique spine centers. The robotic systems used included the Mazor Renaissance, Mazor X, and Mazor Stealth Edition. Patients with incomplete data were excluded from this study. The minimum follow-up was 90 days.

RESULTS

A total of 722 adult patients were included (117 Renaissance, 477 X, 128 Stealth). Most patient and operative factors (e.g., sex, tobacco status, total instrumented levels, and pelvic fixation,) were similar across the years. Mean ± standard deviation Charlson comorbidity index (CCI) was 1.5±1.5. The most commonly reported diagnoses included high grade spondylolisthesis (40.6%), degenerative disc disease (18.4%), and degenerative scoliosis (17.6%). Mean (standard deviation) number of instrumented levels was 3.8±3.4. From 2015 to 2019, average robot time per screw improved from 7.2 to 5.5 minutes (P=0.004, R²=0.649). Average fluoroscopy time per screw improved from 15.2 to 9.4 seconds (P=0.002). Rates of both intraoperative screw exchange for misplaced screw (2015-2016: 2.7%, 2019: 0.8%, P=0.0115, R²=0.1316) and robot abandonment (2015-2016: 7.1%, 2019: 1.1%, P=0.011, R²=0.215) improved significantly over time. The incidence of other intraoperative complications (e.g., dural tear, loss of motor/sensory function, blood transfusion) remained consistently low, but similar throughout the years. The length of stay (LOS) decreased by nearly 1 day from 2015 to 2019 (P=0.007, R²=0.779). 90-day reoperation rates did not change significantly.

CONCLUSIONS

At four institutions among seven surgeons, we demonstrate robot screw accuracy, reliability, operative efficiency, and radiation exposure improved significantly from 2015 to 2019. 90-day complication rates remained low and LOS decreased significantly with time. These findings further validate continued usage of robot-assisted spine surgery and the path toward improved value-based care.

Frameless Robot-Assisted vs Frame-Based Awake Deep Brain Stimulation Surgery: An Evaluation of Technique and New Challenges

BACKGROUND

Methodological approaches to deep brain stimulation (DBS) continue to evolve from awake frame-based to asleep frameless procedures with robotic assistance, primarily directed to optimize operative efficiency, lead accuracy, and patient comfort. Comparison between the 2 is scarce.

OBJECTIVE

To analyze the impacts of methodological differences on operative efficiency and stereotactic accuracy using a frame compared with a frameless robotic platform while maintaining the awake state and use of multiple microelectrode recording (MER) trajectories.

METHODS

Thirty-four consecutive patients who underwent bilateral awake frameless robot-assisted DBS were compared with a previous cohort of 30 patients who underwent frame-based surgery. Patient demographics, operative times, and MER data were collected for both cohorts. Two-dimensional radial errors of lead placements were calculated.

RESULTS

Preoperative setup, surgical, and total operating room times were all significantly greater for the robot-assisted cohort (P < .001). The need for computed tomography imaging when referencing the robotic fiducials led to increased setup duration because of patient transport, unnecessary for the frame-based cohort. Multiple simultaneous MER trajectories increased surgical time (mean 26 min) for the robot-assisted cohort only. The mean radial errors in the robot-assisted and frame cohorts were 0.98 ± 0.66 and 0.74 ± 0.49 mm (P = .03), respectively.

CONCLUSION

The use of a truly frameless robotic platform such as the Mazor Renaissance (Mazor Robotics Ltd) presented challenges when implementing techniques used during awake frame-based surgery. Maintaining good accuracy, intraoperative reference imaging, and limited MER trajectories will help integrate frameless robot assistance into the awake DBS surgical workflow.

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.

Overview of Robotic Technology in Spine Surgery

As robotics in spine surgery has progressed over the past 2 decades, studies have shown mixed results on its clinical outcomes and economic impact. In this review, we highlight the evolution of robotic technology over the past 30 years, discussing early limitations and failures. We provide an overview of the history and evolution of currently available spinal robotic platforms and compare and contrast the available features of each. We conclude by summarizing the literature on robotic instrumentation accuracy in pedicle screw placement and clinical outcomes such as complication rates and briefly discuss the future of robotic spine surgery.

Accuracy and Efficiency of Fusion Robotics™ Versus Mazor-X™ in Single-Level Lumbar Pedicle Screw Placement

Introduction

There has been a surge in robot utilization in spine surgery over the past five years with the rapid development of new spine robotic platforms. This study aimed to compare a new robotic spine platform from Fusion Robotics^TM (Fusion Robotics, Helena, MT) with the widely used Mazor-X^TM Stealth Edition robotic platform (Medtronic, Dublin, Ireland) in terms of workflow and lumbar pedicle screw placement accuracy.

Methods

A cadaver lab was conducted, which included four procedures with single-level lumbar pedicle screw placement using the Fusion Robotics^TM system. These four procedures were compared to four propensity-score matched cases with single-level lumbar pedicle screw placement using the Mazor-X^TM Stealth Edition. A single surgeon performed all surgeries. The cases were matched in terms of demographics (age, sex, race, BMI) and comorbidities (Charlson Comorbidity Index score). The primary outcome measure was the operative workflow efficiency (duration as measured with a stopwatch by an independent observer). The secondary outcome measures were pedicle screw accuracy and accuracy to plan.

Results

After propensity-score matching, there were four cases in each group with no significant between-group differences in terms of sex, race, BMI, or surgical levels; however, there were significant differences in terms of age (p=0.01) and comorbidities (p<0.001). The workflow efficiency measurement showed that the Fusion Robotics^TM platform had a significantly shorter duration in terms of the system set-up time, planning to in-position time, and total procedure time (p<0.05). However, there was no significant difference between the robotic platforms in terms of creating a sterile barrier, scanning and importing images, creating a plan, screw placement, screw accuracy, and screw accuracy to plan.

Conclusion

Based on our findings, the Fusion Robotics^TM platform had a significantly shorter procedure workflow duration while maintaining the same accuracy as the most commonly used robotic platform (Mazor-X^TM). This is the first study to directly compare different spine surgery robotic systems.

Development status of telesurgery robotic system

As an emerging field, telesurgery robotic system is changing the traditional medical mode and can delivery remote surgical treatment anywhere in the world. Advances in telesurgery robotic technology achieve the remote control beyond the current limitation of distance and special medical environment. This review introduces the development history, the current status and the potential in future of the telesurgery robotic system. In addition, it presents the construction of control platform and the application, especially in trauma treatment, as well as the challenge in clinic.

A Systematic Review and Meta-analysis of Randomized Controlled Trials Comparing the Accuracy and Clinical Outcome of Pedicle Screw Placement Using Robot-Assisted Technology and Conventional Freehand Technique

STUDY DESIGN

Systematic review and meta-analysis of randomized controlled trials (RCTs).

OBJECTIVE

This systematic review and meta-analysis was performed with the aim of exploring the differences in pedicle screw positioning accuracy, surgical time, length of hospital stay, postoperative back and leg Visual Analog Scale, revision surgeries, and intraoperative radiation time and exposure between robot-assisted technology and conventional freehand technique based on RCTs.

METHODS

Several databases, including the Cochrane library, PubMed, and EMBASE were systematically searched to identify potentially eligible articles. Meta-analysis was done using STATA 13 software. The odds ratios and 95% CIs were calculated for the studied categories.

RESULTS

Seven RCTs involving 290 patients (1298 pedicle screws) in the robot-assisted group and 288 patients (1348 pedicle screws) in the conventional freehand group were analyzed. The results revealed that grade (A) and grade (A+B) screw accuracies were significantly superior in the robot-assisted group (P = .008 and P = .009, respectively). Overall surgical duration and number of revision surgeries were significantly higher in the robot-assisted group (P = .014 and P < .0001, respectively). Intraoperative radiation time and dosage were significantly lower in the robot-assisted group (P < .0001 and P = .036, respectively).

CONCLUSION

It was demonstrated that robot-assisted technology is superior to the conventional freehand technique in terms of grade (A) and grade (A+B) screw accuracies and in the reduction of intraoperative radiation time and dosage. On the other hand, the freehand technique showed superior results in terms of overall surgical duration and revision surgery rates.

Artificial Intelligence and Robotics in Spine Surgery

STUDY DESIGN

Narrative review.

OBJECTIVES

Artificial intelligence (AI) and machine learning (ML) have emerged as disruptive technologies with the potential to drastically affect clinical decision making in spine surgery. AI can enhance the delivery of spine care in several arenas: (1) preoperative patient workup, patient selection, and outcome prediction; (2) quality and reproducibility of spine research; (3) perioperative surgical assistance and data tracking optimization; and (4) intraoperative surgical performance. The purpose of this narrative review is to concisely assemble, analyze, and discuss current trends and applications of AI and ML in conventional and robotic-assisted spine surgery.

METHODS

We conducted a comprehensive PubMed search of peer-reviewed articles that were published between 2006 and 2019 examining AI, ML, and robotics in spine surgery. Key findings were then compiled and summarized in this review.

RESULTS

The majority of the published AI literature in spine surgery has focused on predictive analytics and supervised image recognition for radiographic diagnosis. Several investigators have studied the use of AI/ML in the perioperative setting in small patient cohorts; pivotal trials are still pending.

CONCLUSIONS

Artificial intelligence has tremendous potential in revolutionizing comprehensive spine care. Evidence-based, predictive analytics can help surgeons improve preoperative patient selection, surgical indications, and individualized postoperative care. Robotic-assisted surgery, while still in early stages of development, has the potential to reduce surgeon fatigue and improve technical precision.

Frameless Robot-Assisted Deep Brain Stimulation Surgery: An Initial Experience

BACKGROUND

Modern robotic-assist surgical systems have revolutionized stereotaxy for a variety of procedures by increasing operative efficiency while preserving and even improving accuracy and safety. However, experience with robotic systems in deep brain stimulation (DBS) surgery is scarce.

OBJECTIVE

To present an initial series of DBS surgery performed utilizing a frameless robotic solution for image-guided stereotaxy, and report on operative efficiency, stereotactic accuracy, and complications.

METHODS

This study included the initial 20 consecutive patients undergoing bilateral robot-assisted DBS. The prior 20 nonrobotic, frameless cohort of DBS cases was sampled as a baseline historic control. For both cohorts, patient demographic and clinical data were collected including postoperative complications. Intraoperative duration and number of Microelectrode recording (MER) and final lead passes were recorded. For the robot-assisted cohort, 2D radial errors were calculated.

RESULTS

Mean case times (total operating room, anesthesia, and operative times) were all significantly decreased in the robot-assisted cohort (all P-values < .02) compared to frameless DBS. When looking at trends in case times, operative efficiency improved over time in the robot-assisted cohort across all time assessment points. Mean radial error in the robot-assisted cohort was 1.40 ± 0.11 mm, and mean depth error was 1.05 ± 0.18 mm. There was a significant decrease in the average number of MER passes in the robot-assisted cohort (1.05) compared to the nonrobotic cohort (1.45, P < .001).

CONCLUSION

This is the first report of application of frameless robotic-assistance with the Mazor Renaissance platform (Mazor Robotics Ltd, Caesarea, Israel) for DBS surgery, and our findings reveal that an initial experience is safe and can have a positive impact on operative efficiency, accuracy, and safety.

Robotic spine surgery: a review of the present status

With technological advancements being introduced and dominating many fields, spine surgery is no exception. In view of the patient safety and surgeon's comfort, robotics has been introduced in spine surgery. Due to small corridors for work, little room for inaccuracy, lengthy and tedious procedures, spine surgery is an ideal scenario for robotics to establish as the standard of care. Spine robotics received their first FDA clearance in 2004. New generation of spine robotics with integrated navigation systems has become available now. The primary role of spine robotics, at present, is to aid pedicle screw fixation. High quality studies have been performed to establish its role in increasing the accuracy of pedicle fixation. Studies have also reported decreased radiation and decreased operative time with spine robotics. However, few studies have reported otherwise. It is still in its nascent stage in both industrial view and surgeon familiarity. Continued research to overcome the challenges such as high cost and steep learning curve is crucial for its widespread use. Also, expanding the scope of spine robotics beyond pedicle screw fixation such as osteotomies and dural procedures would be an area for potential research. This review is intended to provide an overview of various studies in the field of robotic spine surgery and its present status.

Accuracy of robot-assisted versus conventional freehand pedicle screw placement in spine surgery: a systematic review and meta-analysis of randomized controlled trials

This systematic review and meta-analysis investigated differences in accuracy, operation time, and radiation exposure time between robot-assisted and freehand techniques for pedicle screw insertion. Two investigators independently searched for articles on randomized controlled trials (RCTs) published from 2012 to 2019. The final meta-analysis included seven RCTs. We compared the accuracy of pedicle screw placement, operation time, and radiation exposure time between robot-assisted and conventional freehand groups. Seven RCTs included 540 patients and placement of 2,476 pedicle screws, of which 1,220 were inserted using the robot-assisted technique and 1,256 were inserted using the conventional freehand technique. The pedicle screw positions were classified using the Gertzbein and Robbins classification (grade A-E). The combined results of Grade A [odds ratio (OR) =1.68; 95% confidence intervals (CI): 0.82-3.44; P=0.16), Grade A+B (OR =1.70; 95% CI: 0.47-6.13; P=0.42), and Grade C+D+E (OR =0.59; 95% CI: 0.16-2.12; P=0.42) for the accuracy rate revealed no significant difference between the two groups. Subgroup analysis results revealed that the TiRobot-assisted technique presented a significantly improved pedicle screw insertion accuracy rate compared with that of the conventional freehand technique, based on Grade A, Grade A+B, and Grade C+D+E classifications. The SpineAssist-assisted technique presented an inferior pedicle screw insertion accuracy rate compared with that of the conventional freehand technique, based on Grade A, Grade A+B, and Grade C+D+E classifications. No difference between the Renaissance-assisted and conventional freehand techniques was noted for pedicle screw insertion accuracy rates, based on both Grade A (OR =1.58; 95% CI: 0.85-2.96; P=0.15), Grade A+B (OR =2.20; 95% CI: 0.39-12.43; P=0.37), and Grade C+D+E (OR =0.45; 95% CI: 0.08-2.56; P=0.37) classifications. Regarding operation time, robot-assisted surgery had significantly longer operation time than conventional freehand surgery. The robot-assisted group had significantly shorter radiation exposure time. Regarding the pedicle screw insertion accuracy rate, the TiRobot-assisted technique was superior, the SpineAssist-assisted technique was inferior, and Renaissance was similar to the conventional freehand technique.

Design and control of an image-guided robot for spine surgery in a hybrid OR

BACKGROUND

Minimally invasive spine (MIS) fusion surgery requires image guidance and expert manual dexterity for a successful, efficient, and accurate pedicle screw placement. Operating room (OR)-integrated robotic solution can provide precise assistance to potentially minimize complication rates and facilitate difficult MIS procedures.

METHODS

A 5-degrees of freedom robot was designed specifically for a hybrid OR with integrated surgical navigation for guiding pedicle screw pilot holes. The system automatically aligns an instrument following the surgical plan using only instrument tracking feedback. Contrary to commercially available robotic systems, no tracking markers on the robotic arm are required. The system was evaluated in a cadaver study.

RESULTS

The mean targeting error (N = 34) was 1.27±0.57 mm and 1.62±0.85°, with 100% of insertions graded as clinically acceptable.

CONCLUSIONS

A fully integrated robotic guidance system, including intra-op imaging, planning, and physical guidance with optimized robot design and control, can improve workflow and provide pedicle screw guidance with less than 2 mm targeting error.

Does Three-Dimensional Printed Patient-Specific Templates Add Benefit in Revision Surgeries for Complex Pediatric Kyphoscoliosis Deformity with Sublaminar Wires in Situ? A Clinical Study

STUDY DESIGN

Case-control study.

PURPOSE

To evaluate the accuracy of three-dimensional (3D) printed patient-specific templates (PSTs) for placement of pedicle screws (PAs) in patients undergoing revision surgeries for complex kyphoscoliosis deformity with sublaminar wires in situ.

OVERVIEW OF LITERATURE

Revision kyphoscoliosis correction surgery in pediatric patients is a challenging task for the treating surgeon. In patients with sublaminar wires in situ, the native anatomical landmarks are obscured, thus making the freehand screw placement technique a highly specialized task. Hence, the concept of using PSTs for insertion of PAs in such surgeries is always intriguing and attractive.

METHODS

Five consecutive patients undergoing revision deformity correction with sublaminar wires in situ were included in this study. Patients were divided in two groups based on the technique of PA insertion. A total of 91 PAs were inserted using either a freehand technique (group A) or 3D printed templates (group B) (34 vs. 57). The placement of PAs was classified according to a postoperative computed tomography scan using Neo's classification. Perforation beyond class 2 (>2 mm) was termed as a misplaced screw. The average time required for the insertion of screws was also noted.

RESULTS

Mean age, surgical time, and blood loss were recorded. The change in mean Cobb's angle in both groups was also recorded. The difference in rates of misplaced screws was noted in group A and group B (36.21% vs. 2.56%); however, the mean number of misplaced PAs per patient in group A and group B was statistically insignificant (6.5±3.54 vs. 4.67±1.53, p =0.4641). The mean time required to insert a single PA was also statistically insignificant (120±28.28 vs. 90±30 seconds, p =0.3456).

CONCLUSIONS

Although 3D printed PSTs help to avoid the misplacement of PAs in revision deformity correction surgeries with sublaminar wires in situ, the mean number of misplaced screws per patient using this technique was found to be statistically insignificant when compared with the freehand technique in this study.

Robotic-Assisted Spine Surgery: History, Efficacy, Cost, And Future Trends

Robot-assisted spine surgery has recently emerged as a viable tool to enable less invasive and higher precision surgery. The first-ever spine robot, the SpineAssist (Mazor Robotics Ltd., Caesarea, Israel), gained FDA approval in 2004. With its ability to provide real-time intraoperative navigation and rigid stereotaxy, robotic-assisted surgery has the potential to increase accuracy while decreasing radiation exposure, complication rates, operative time, and recovery time. Currently, robotic assistance is mainly restricted to spinal fusion and instrumentation procedures, but recent studies have demonstrated its use in increasingly complex procedures such as spinal tumor resections and ablations, vertebroplasties, and deformity correction. However, robots do require high initial costs and training, and thus, require justification for their incorporation into common practice. In this review, we discuss the history of spinal robots along as well as currently available systems. We then examine the literature to evaluate accuracy, operative time, complications, radiation exposure, and costs – comparing robotic-assisted to traditional fluoroscopy-assisted freehand approaches. Finally, we consider future applications for robots in spine surgery.

What should my hospital buy next?-Guidelines for the acquisition and application of imaging, navigation, and robotics for spine surgery

The range of assistive technology options available for spinal fusion surgery has significantly increased. However, surgeons and hospital administrators may lack sufficient information to compare options and make purchasing decisions. We summarize currently available navigation, robotics, and imaging technologies for spinal surgery, highlighting key characteristics, utility, differences, price, and compatibility with other technologies and spinal implants. Guidelines for optimal use and combinations are provided based on surgical approach, operative site, patient anatomy, optimal image quality, and workflow efficiency. Key recommendations include the following. (I) Open-platform navigation and robotics systems that provide surgeons with access to all software and hardware features regardless of implant choice are preferred. (II) Imaging systems that have maximum compatibility with navigation and robotics platforms are optimal. (III) Navigation systems that offer a universal registration mechanism should be standard. (IV) 3D fluoroscopy provides the greatest benefit when speed, operative efficiency, and mobility are required. (V) Intraoperative CT is more useful for imaging long constructs, high BMI, or cervicothoracic anatomy. (VI) Radiation safety awareness that new 3D-fluoroscopy units can deliver radiation comparable to that of CT is needed. (VII) New robotic arm platforms require more clinical and health economic data to justify increased costs.

The Arrival of Robotics in Spine Surgery: A Review of the Literature

STUDY DESIGN

Systematic review.

OBJECTIVE

The authors aim to review comparative outcome measures between robotic and free-hand spine surgical procedures including: accuracy of spinal instrumentation, radiation exposure, operative time, hospital stay, and complication rates.

SUMMARY OF BACKGROUND DATA

Misplacement of pedicle screws in conventional open as well as minimally invasive surgical procedures has prompted the need for innovation and allowed the emergence of robotics in spine surgery. Before incorporation of robotic surgery in routine practice, demonstration of improved instrumentation accuracy, operative efficiency, and patient safety are required.

METHODS

A systematic search of the PubMed, OVID-MEDLINE, and Cochrane databases was performed for articles relevant to robotic assistance of pedicle screw placement. Inclusion criteria were constituted by English written randomized control trials, prospective and retrospective cohort studies involving robotic instrumentation in the spine. Following abstract, title, and full-text review, 32 articles were selected for study inclusion.

RESULTS

Intrapedicular accuracy in screw placement and subsequent complications were at least comparable if not superior in the robotic surgery cohort. There is evidence supporting that total operative time is prolonged in robot-assisted surgery compared to conventional free-hand. Radiation exposure appeared to be variable between studies; radiation time did decrease in the robot arm as the total number of robotic cases ascended, suggesting a learning curve effect. Multilevel procedures appeared to tend toward earlier discharge in patients undergoing robotic spine surgery.

CONCLUSION

The implementation of robotic technology for pedicle screw placement yields an acceptable level of accuracy on a highly consistent basis. Surgeons should remain vigilant about confirmation of robotic-assisted screw trajectory, as drilling pathways have been shown to be altered by soft tissue pressures, forceful surgical application, and bony surface skiving. However, the effective consequence of robot-assistance on radiation exposure, length of stay, and operative time remains unclear and requires meticulous examination in future studies.

LEVEL OF EVIDENCE

4.

Robotics in trauma and orthopaedics

Recent advances and review of literature

Current applications of robotics in spine surgery: a systematic review of the literature

OBJECTIVE Surgical robotics has demonstrated utility across the spectrum of surgery. Robotics in spine surgery, however, remains in its infancy. Here, the authors systematically review the evidence behind robotic applications in spinal instrumentation. METHODS This systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. Relevant studies (through October 2016) that reported the use of robotics in spinal instrumentation were identified from a search of the PubMed database. Data regarding the accuracy of screw placement, surgeon learning curve, radiation exposure, and reasons for robotic failure were extracted. RESULTS Twenty-five studies describing 2 unique robots met inclusion criteria. Of these, 22 studies evaluated accuracy of spinal instrumentation. Although grading of pedicle screw accuracy was variable, the most commonly used method was the Gertzbein and Robbins system of classification. In the studies using the Gertzbein and Robbins system, accuracy (Grades A and B) ranged from 85% to 100%. Ten studies evaluated radiation exposure during the procedure. In studies that detailed fluoroscopy usage, overall fluoroscopy times ranged from 1.3 to 34 seconds per screw. Nine studies examined the learning curve for the surgeon, and 12 studies described causes of robotic failure, which included registration failure, soft-tissue hindrance, and lateral skiving of the drill guide. CONCLUSIONS Robotics in spine surgery is an emerging technology that holds promise for future applications. Surgical accuracy in instrumentation implanted using robotics appears to be high. However, the impact of robotics on radiation exposure is not clear and seems to be dependent on technique and robot type.

A 6-DOF parallel bone-grinding robot for cervical disc replacement surgery

Artificial cervical disc replacement surgery has become an effective and main treatment method for cervical disease, which has become a more common and serious problem for people with sedentary work. To improve cervical disc replacement surgery significantly, a 6-DOF parallel bone-grinding robot is developed for cervical bone-grinding by image navigation and surgical plan. The bone-grinding robot including mechanical design and low level control is designed. The bone-grinding robot navigation is realized by optical positioning with spatial registration coordinate system defined. And a parametric robot bone-grinding plan and high level control have been developed for plane grinding for cervical top endplate and tail endplate grinding by a cylindrical grinding drill and spherical grinding for two articular surfaces of bones by a ball grinding drill. Finally, the surgical flow for a robot-assisted cervical disc replacement surgery procedure is present. The final experiments results verified the key technologies and performance of the robot-assisted surgery system concept excellently, which points out a promising clinical application with higher operability. Finally, study innovations, study limitations, and future works of this present study are discussed, and conclusions of this paper are also summarized further. This bone-grinding robot is still in the initial stage, and there are many problems to be solved from a clinical point of view. Moreover, the technique is promising and can give a good support for surgeons in future clinical work.

Evidence for robots

Robots have been successfully used in commercial industry and have enabled humans to perform tasks which are repetitive, dangerous and requiring extreme force. Their role has evolved and now includes many aspects of surgery to improve safety and precision. Orthopaedic surgery is largely performed on bones which are rigid immobile structures which can easily be performed by robots with great precision. Robots have been designed for use in orthopaedic surgery including joint arthroplasty and spine surgery. Experimental studies have been published evaluating the role of robots in arthroscopy and trauma surgery. In this article, we will review the incorporation of robots in orthopaedic surgery looking into the evidence in their use.

Accuracy of Pedicle Screw Placement with Robotic Guidance System: A Cadaveric Study

STUDY DESIGN

A cadaveric study.

OBJECTIVE

To investigate the accuracy of pedicle screw placement using a robotic guidance system (RGS).

SUMMARY OF BACKGROUND DATA

RGS is a unique surgery assistance-apparatus. Although several clinical studies have demonstrated that RGS provides accurate pedicle screw placement, very few studies have validated its accuracy.

METHODS

A total of 216 trajectories performed with the assistance of the RGS in eight cadavers were evaluated. The RGS was used, with different mounting platforms, to drill pilot holes in the thoracic and lumbosacral spine, using 3-mm diameter fiducial wires as trajectory markers. Deviation between the preoperative plan and executed trajectories was measured at the entry points to the vertebrae and at a depth of 30 mm along the wire. Both the deviation from the preoperative plan and the wire position were evaluated in the axial and sagittal planes using computed tomography (CT).

RESULTS

The average deviation from the planned wire placement was 0.64 ± 0.59 mm at the entry point and 0.63 ± 0.57 mm at a depth of 30 mm in the axial plane, and 0.77 ± 0.62 mm and 0.80 ± 0.66 mm, respectively, in the sagittal plane. The magnitude of deviation was not affected by the vertebral level or the platform used. The use of an open approach achieved greater screw placement accuracy at a depth of 30 mm in the sagittal plane, compared with the percutaneous approach. The fiducials were placed completely within the pedicle in 93.9% of trajectories in the axial plane (n = 164 pedicles with a width ≥5 mm) and 98.6% in the sagittal plane (n = 216).

CONCLUSION

In this cadaveric study, RGS supported execution of accurate trajectories that were equal or slightly superior to reports of CT-based navigation systems.

LEVEL OF EVIDENCE

N/A.

Robotic surgery in trauma and orthopaedics: a systematic review

The use of robots in orthopaedic surgery is an emerging field that is gaining momentum. It has the potential for significant improvements in surgical planning, accuracy of component implantation and patient safety. Advocates of robot-assisted systems describe better patient outcomes through improved pre-operative planning and enhanced execution of surgery. However, costs, limited availability, a lack of evidence regarding the efficiency and safety of such systems and an absence of long-term high-impact studies have restricted the widespread implementation of these systems. We have reviewed the literature on the efficacy, safety and current understanding of the use of robotics in orthopaedics.

Learning curve of 3D fluoroscopy image-guided pedicle screw placement in the thoracolumbar spine

BACKGROUND CONTEXT

During the past decade, a disproportionate increase of spinal fusion procedures has been observed. Along with this trend, image-guided spine surgery has been experiencing a renaissance in the recent years. A wide range of different navigation systems are available on the market today. However, only few published studies assess the learning curves concerning these new spinal navigation techniques. So far, a study on the learning curve for intraoperative three-dimensional fluoroscopy (3DFL)-navigated pedicle screw (PS) placement is still lacking.

PURPOSE

The purpose of the study was to analyze the learning curve for 3DFL-navigated thoracolumbar PS placement.

STUDY DESIGN/SETTING

The study design included a prospective case series.

PATIENT SAMPLE

A cohort of 145 patients were recruited from January 2011 to June 2012.

OUTCOME MEASURES

The outcome measures were duration of intraoperative 3D scans, PS placement, PS accuracy on postoperative computed tomography (CT) scans, and PS-related revisions and complications.

METHODS

From the introduction of spinal navigation to our department in January 2011 until June 2012, the learning curve for the duration of intraoperative 3D scan acquisition (navigation or control scan) and placement time per screw, intraoperative screw revisions, screw-related complications, revision surgeries, and PS accuracy on postoperative CT scans were assessed in 145 patients undergoing dorsal navigated instrumentation for 928 PS (736 lumbosacral and 192 thoracic). The observed time span was divided into four intervals. Results of the second, third, and last periods were compared with the first (reference) period, respectively.

RESULTS

The mean navigation 3D scan time decreased (first and fourth periods) from 15.4±7.8 (range, 4-40) to 8.4±3.3 (3-15) minutes (p<.001). The mean control 3D scan time (after PS placement) decreased from 11.2±4.8 (5-25) to 6.6±3.0 (3-15) minutes (p<.001). The mean PS insertion time decreased from 5.3±2.5 (1-15) to 3.2±2.3 (1-17) minutes (p<.001). The mean proportion of correctly positioned PS (all 928) according to the Gertzbein and Robbins classification grades A and B increased initially from 83.1% (first period) to 95.1% (second period, p=.001), 96.4% (third period, p=.002), and 92.4% (fourth period, p=.049). No learning effect was found with respect to intraoperative screw revisions. There was one revision surgery.

CONCLUSIONS

We could demonstrate significant learning effects for 3DFL-navigated PS placement with regard to intraoperative 3D scan acquisition, PS placement time, and PS accuracy.

Robotics and the spine: a review of current and ongoing applications

OBJECT

Robotics in the operating room has shown great use and versatility in multiple surgical fields. Robot-assisted spine surgery has gained significant favor over its relatively short existence, due to its intuitive promise of higher surgical accuracy and better outcomes with fewer complications. Here, the authors analyze the existing literature on this growing technology in the era of minimally invasive spine surgery.

METHODS

In an attempt to provide the most recent, up-to-date review of the current literature on robotic spine surgery, a search of the existing literature was conducted to obtain all relevant studies on robotics as it relates to its application in spine surgery and other interventions.

RESULTS

In all, 45 articles were included in the analysis. The authors discuss the current status of this technology and its potential in multiple arenas of spinal interventions, mainly spine surgery and spine biomechanics testing.

CONCLUSIONS

There are numerous potential advantages and limitations to robotic spine surgery, as suggested in published case reports and in retrospective and prospective studies. Randomized controlled trials are few in number and show conflicting results regarding accuracy. The present limitations may be surmountable with future technological improvements, greater surgeon experience, reduced cost, improved operating room dynamics, and more training of surgical team members. Given the promise of robotics for improvements in spine surgery and spine biomechanics testing, more studies are needed to further explore the applicability of this technology in the spinal operating room. Due to the significant cost of the robotic equipment, studies are needed to substantiate that the increased equipment costs will result in significant benefits that will justify the expense.

Robotics in keyhole transcranial endoscope-assisted microsurgery: a critical review of existing systems and proposed specifications for new robotic platforms

BACKGROUND

Over the past decade, advances in image guidance, endoscopy, and tube-shaft instruments have allowed for the further development of keyhole transcranial endoscope-assisted microsurgery, utilizing smaller craniotomies and minimizing exposure and manipulation of unaffected brain tissue. Although such approaches offer the possibility of shorter operating times, reduced morbidity and mortality, and improved long-term outcomes, the technical skills required to perform such surgery are inevitably greater than for traditional open surgical techniques, and they have not been widely adopted by neurosurgeons. Surgical robotics, which has the ability to improve visualization and increase dexterity, therefore has the potential to enhance surgical performance.

OBJECTIVE

To evaluate the role of surgical robots in keyhole transcranial endoscope-assisted microsurgery.

METHODS

The technical challenges faced by surgeons utilizing keyhole craniotomies were reviewed, and a thorough appraisal of presently available robotic systems was performed.

RESULTS

Surgical robotic systems have the potential to incorporate advances in augmented reality, stereoendoscopy, and jointed-wrist instruments, and therefore to significantly impact the field of keyhole neurosurgery. To date, over 30 robotic systems have been applied to neurosurgical procedures. The vast majority of these robots are best described as supervisory controlled, and are designed for stereotactic or image-guided surgery. Few telesurgical robots are suitable for keyhole neurosurgical approaches, and none are in widespread clinical use in the field.

CONCLUSION

New robotic platforms in minimally invasive neurosurgery must possess clear and unambiguous advantages over conventional approaches if they are to achieve significant clinical penetration.

Use of three-dimensional fluoroscopy to determine intra-articular screw penetration in proximal humeral fracture model

BACKGROUND

Proximal humeral locking plates have significantly improved the treatment of proximal humeral fractures in recent years; however, they are not devoid of complications. Inadvertent screw penetration into the joint is a well-documented complication. Intraoperative 3-dimensional (3D) imaging may assist in detecting intra-articular implant penetration. This study compared the performance of a standard C-arm fluoroscope with a novel 3D imaging fluoroscope in detecting penetrating implants in a proximal humeral fracture model.

METHODS

Zinc-sprayed proximal humerus sawbones were affixed with a proximal humeral locking plate. Six different constructs were assembled. In each specimen, 1 screw, 2 screws, or no screws were inserted 2-mm proud of the articular surface. Each specimen was imaged with a conventional fluoroscope and a 3D imaging fluoroscope. Overall, 36 image sets were prepared for each modality. These were evaluated by 2 fellowship-trained surgeons for intraobserver and interobserver reliability as well for the accuracy of detecting prominent implants in the 2 imaging methods.

RESULTS

Overall accuracy for observer A was 89.9% compared with 100% for C-arm fluoroscopy and 3D imaging fluoroscopy (P < .01) and for observer B was 91.1% and 100% (P = .01), respectively. The κ values were 0.74 with C-arm fluoroscopy and 1.0 for the 3D imaging fluoroscopy for observer A, and 0.93 and 1.0, respectively, for observer B.

CONCLUSIONS

In a proximal humeral fracture model, C-arm fluoroscopy is a highly accurate imaging modality that can minimize the incidence of penetrating screws into the joint. Further clinical studies are required to establish this modality.

A robot-assisted surgical system using a force-image control method for pedicle screw insertion

Objective

To introduce a robot-assisted surgical system for spinal posterior fixation that can automatically recognize the drilling state and stop potential cortical penetration with force and image information and to further evaluate the accuracy and safety of the robot for sheep vertebra pedicle screw placement.

Methods

The Robotic Spinal Surgery System (RSSS) was composed of an optical tracking system, a navigation and planning system, and a surgical robot equipped with a 6-DOF force/torque sensor. The robot used the image message and force signals to sense the different operation states and to prevent potential cortical penetration in the pedicle screw insertion operation. To evaluate the accuracy and safety of the RSSS, 32 screw insertions were conducted. Furthermore, six trajectories were deliberately planned incorrectly to explore whether the robot could recognize the different drilling states and immediately prevent cortical penetration.

Results

All 32 pedicle screws were placed in the pedicle without any broken pedicle walls. Compared with the preoperative planning, the average deviations of the entry points in the axial and sagittal views were 0.50±0.33 and 0.65±0.40 mm, and the average deviations of the angles in the axial and sagittal views were 1.9±0.82° and 1.48±1.2°. The robot successfully recognized the different drilling states and prevented potential cortical penetration. In the deliberately incorrectly planned trajectory experiments, the robot successfully prevented the cortical penetration.

Conclusion

These results verified the RSSS’s accuracy and safety, which supported its potential use for the spinal surgery.

Navigation, robotics, and intraoperative imaging in spinal surgery

Spinal navigation is a technique gaining increasing popularity. Different approaches as CT-based or intraoperative imaging-based navigation are available, requiring different methods of patient registration, bearing certain advantages and disadvantages. So far, a large number of studies assessed the accuracy of pedicle screw implantation in the cervical, thoracic, and lumbar spine, elucidating the advantages of image guidance. However, a clear proof of patient benefit is missing, so far. Spinal navigation is closely related to intraoperative 3D imaging providing an imaging dataset for navigational use and the opportunity for immediate intraoperative assessment of final screw position giving the option of immediate screw revision if necessary. Thus, postoperative imaging and a potential revision surgery for screw correction become dispensable.Different concept of spinal robotics as the DaVinci system and SpineAssist are under investigation.

Robot-assisted and fluoroscopy-guided pedicle screw placement: a systematic review

PURPOSE

At present, most spinal surgeons undertake pedicle screw implantation using either anatomical landmarks or C-arm fluoroscopy. Reported rates of screw malposition using these techniques vary considerably, though the evidence generally favors the use of image-guidance systems. A miniature spine-mounted robot has recently been developed to further improve the accuracy of pedicle screw placement. In this systematic review, we critically appraise the perceived benefits of robot-assisted pedicle screw placement compared to conventional fluoroscopy-guided technique.

METHODS

The Cochrane Central Register of Controlled Trials, PubMed, and EMBASE databases were searched between January 2006 and January 2013 to identify relevant publications that (1) featured placement of pedicle screws, (2) compared robot-assisted and fluoroscopy-guided surgery, (3) assessed outcome in terms of pedicle screw position, and (4) present sufficient data in each arm to enable meaningful comparison (>10 pedicle screws in each study group).

RESULTS

A total of 246 articles were retrieved, of which 5 articles met inclusion criteria, collectively reporting placement of 1,308 pedicle screws (729 robot-assisted, 579 fluoroscopy-guided). The findings of these studies are mixed, with limited higher level of evidence data favoring fluoroscopy-guided procedures, and remaining comparative studies supporting robot-assisted pedicle screw placement.

CONCLUSIONS

There is insufficient evidence to unequivocally recommend one surgical technique over the other. Given the high cost of robotic systems, and the high risk of spinal surgery, further high quality studies are required to address unresolved clinical equipoise in this field.

The future of spine surgery: New horizons in the treatment of spinal disorders

Background and Methods:

As with any evolving surgical discipline, it is difficult to predict the future of the practice and science of spine surgery. In the last decade, there have been dramatic developments in both the techniques as well as the tools employed in the delivery of better outcomes to patients undergoing such surgery. In this article, we explore four specific areas in spine surgery: namely the role of minimally invasive spine surgery; motion preservation; robotic-aided surgery and neuro-navigation; and the use of biological substances to reduce the number of traditional and revision spine surgeries.

Results:

Minimally invasive spine surgery has flourished in the last decade with an increasing amount of surgeries being performed for a wide variety of degenerative, traumatic, and neoplastic processes. Particular progress in the development of a direct lateral approach as well as improvement of tubular retractors has been achieved. Improvements in motion preservation techniques have led to a significant number of patients achieving arthroplasty where fusion was the only option previously. Important caveats to the indications for arthroplasty are discussed. Both robotics and neuro-navigation have become further refined as tools to assist in spine surgery and have been demonstrated to increase accuracy in spinal instrumentation placement. There has much debate and refinement in the use of biologically active agents to aid and augment function in spine surgery. Biological agents targeted to the intervertebral disc space could increase function and halt degeneration in this anatomical region.

Conclusions:

Great improvements have been achieved in developing better techniques and tools in spine surgery. It is envisaged that progress in the four focus areas discussed will lead to better outcomes and reduced burdens on the future of both our patients and the health care system.

Evaluation of an Experimentally Designed Stereotactic Guidance System for Determining Needle Entry Point during Uniplanar Fluoroscopy-guided Intervention

Background

In discography performed during percutaneous endoscopic lumbar discectomy (PELD) via the posterolateral approach, it is difficult to create a fluoroscopic tunnel view because a long needle is required for discography and the guide-wire used for consecutive PELD interrupts rotation of fluoroscope. A stereotactic system was designed to facilitate the determination of the needle entry point, and the feasibility of this system was evaluated during interventional spine procedures.

Methods

A newly designed stereotactic guidance system underwent a field test application for PELD. Sixty patients who underwent single-level PELD at L4-L5 were randomly divided into conventional or stereotactic groups. PELD was performed via the posterolateral approach using the entry point on the skin determined by premeasured distance from the midline and angles according to preoperative magnetic resonance imaging (MRI) findings. Needle entry accuracy provided by the two groups was determined by comparing the distance and angle measured by postoperative computed tomography with those measured by preoperative MRI. The duration and radiation exposure for determining the entry point were measured in the groups.

Results

The new stereotactic guidance system and the conventional method provided similarly accurate entry points for discography and consecutive PELD. However, the new stereotactic guidance system lowered the duration and radiation exposure for determining the entry point.

Conclusions

The new stereotactic guidance system under fluoroscopy provided a reliable needle entry point for discography and consecutive PELD. Furthermore, it reduced the duration and radiation exposure associated with determining needle entry.

Computed tomography-guided navigation of thoracic pedicle screws for adolescent idiopathic scoliosis results in more accurate placement and less screw removal

STUDY DESIGN

Retrospective study of computed tomography-guided navigation (CTGN) of thoracic pedicle screw placement in patients with adolescent idiopathic scoliosis (AIS).

OBJECTIVE

To compare the accuracy and safety of thoracic pedicle screw placement and frequency of intraoperative removal using CTGN versus conventional freehand technique in AIS.

SUMMARY OF BACKGROUND DATA

Even in experienced hands, more than 10% of the thoracic pedicle screws are misplaced. CTGN may improve accuracy and safety, but there is little published data on its efficacy.

METHODS

We reviewed intraoperative computed tomographic images in a consecutive series of AIS cases undergoing posterior fusion during a 1-year period. Three types of screws were identified: an optimal screw--the central axis is in the plane and axis of the pedicle with the tip completely within the vertebral body; an acceptable screw--the majority of its shank is outside the central axis of the pedicle, but not potentially unsafe; and a potentially unsafe screw--(1) the central axis of the screw traversed the canal, (2) left anterior/lateral vertebral body perforation, risking the aorta, or (3) any screw repositioned or removed after the postimplant computed tomography.

RESULTS

In 42 patients, 485 screws were evaluable with a visible pedicle and screw (300 navigated and 185 non-navigated). Screws were classified as follows: optimal screws, 74% CTGN versus 42% non-navigated; acceptable screws, 23% CTGN versus 49% non-navigated; and potentially unsafe, 3% CTGN versus 9% non-navigated (P < 0.001). A potentially unsafe screw was 3.8 times less likely to be inserted with navigation (P = 0.003). The odds of a significant medial breach were 7.6 times higher without navigation (P < 0.001). A screw was 8.3 times more likely to be removed intraoperatively in the non-navigated cohort (P = 0.003).

CONCLUSION

CTGN resulted in more optimally placed thoracic pedicle screws, fewer potentially unsafe screws, and fewer screw removals.

Accuracy of robot-assisted placement of lumbar and sacral pedicle screws: a prospective randomized comparison to conventional freehand screw implantation

STUDY DESIGN

Single-center prospective randomized controlled study.

OBJECTIVE

To evaluate the accuracy of robot-assisted (RO) implantation of lumbar/sacral pedicle screws in comparison with the freehand (FH) conventional technique.

SUMMARY OF BACKGROUND DATA

SpineAssist is a miniature robot for the implantation of thoracic, lumbar, and sacral pedicle screws. The system, studied in cadaver and cohort studies, revealed a high accuracy, so far. A direct comparison of the robot assistance with the FH technique is missing.

METHODS

Patients requiring mono- or bisegmental lumbar or lumbosacral stabilization were randomized in a 1:1 ratio to FH or RO pedicle screw implantation. Instrumentation was performed using fluoroscopic guidance (FH) or robot assistance. The primary end point screw position was assessed by a postoperative computed tomography, and screw position was classified (A: no cortical violation; B: cortical breach <2 mm; C: ≥2 mm to <4 mm; D: ≥4 mm to <6 mm; E: ≥6 mm). Secondary end points as radiation exposure, duration of surgery/planning, and hospital stay were assessed.

RESULTS

A total of 298 pedicle screws were implanted in 60 patients (FH, 152; RO, 146). Ninety-three percent had good positions (A or B) in FH, and 85% in RO. Preparation time in the operating room (OR), overall OR time, and intraoperative radiation time were not different for both groups. Surgical time for screw placement was significantly shorter for FH (84 minutes) than for RO (95 minutes). Ten RO screws required an intraoperative conversion to the FH. One FH screw needed a secondary revision.

CONCLUSION

In this study, the accuracy of the conventional FH technique was superior to the RO technique. Most malpositioned screws of the RO group showed a lateral deviation. Attachment of the robot to the spine seems a vulnerable aspect potentially leading to screw malposition as well as slipping of the implantation cannula at the screw entrance point.

Advances in medical robotic systems with specific applications in surgery--a review

Although robotics was started as a form of entertainment, it gradually became used in different branches of science. Medicine, particularly in the operating room, has been influenced significantly by this field. Robotic technologies have offered valuable enhancements to medical or surgical processes through improved precision, stability and dexterity. In this paper we review different robotics and computer-assisted systems developed with medical and surgical applications. We cover early and recently developed systems in different branches of surgery. In addition to the united operational systems, we provide a review of miniature robotic, diagnostic and sensory systems developed to assist or collaborate with a main operator system. At the end of the paper, a discussion is given with the aim of summarizing the proposed points and predicting the future of robotics in medicine.