Robotic-guided placement of cervical pedicle screws: feasibility and accuracy

Accuracy and Safety Assessment of Subaxial Cervical Pedicle Screw Instrumentation: A Systematic Review

BACKGROUND CONTEXT

Given increasing use of both cervical pedicle screw (CPS) fixation in the subaxial cervical spine (C3-C7) and emerging navigation technologies, a quantitative profile of safety and accuracy remains wanting. Compared with lateral mass instrumentation of this region, CPS fixation shows superior biomechanical properties but poses higher risk of complications because of the narrow cervical pedicle width and proximity to neurovascular structures.

PURPOSE

This systematic review quantifies the accuracy and safety of all types of subaxial CPS insertion, with or without navigation or template-based methods, to weigh the strengths and limitations of each technique.

STUDY DESIGN

Systematic review according to PRISMA guidelines.

PATIENT SAMPLE

Patients who underwent CPS instrumentation since its introduction.

OUTCOME MEASURES

Primary and secondary outcomes in our review included pedicle screw breach in the subaxial cervical spine determined on intra- or postoperative imaging, and screw-related operative complications, respectively.

METHODS

Following the PRISMA guidelines, our literature search of PubMed, Cochrane, and Scopus databases identified 3,312 clinical studies (1980-2024) using subaxial CPS that assessed for screw accuracy. After full-text analysis, data extracted included number of CPS, level of placement, number of patients, indications, insertion techniques, accuracy assessment method, classification of accuracy, breach rate, complication rate, and study origin.

RESULTS

The 73 studies included in final analysis from Asia (80%), Europe (12%) and North America (8%) yielded 14,118 CPS in 3,342 patients (1999-2024). Accuracy rates were 85.3% for 10,108 CPS placed with non-navigated techniques (free-hand and fluoroscopy), 82.7% for 3,067 with navigation techniques, and 96.3% for 943 CPS placed using 3D templates. Complication rates were 1.1%, 2.1%, and zero, respectively.

CONCLUSION

Our comprehensive review of more than 14,000 subaxial CPSs inserted found rates of high 84% overall accuracy and low 1.2% perioperative complications (i.e., attributed to a misplaced screw). With biomechanical advantages superior to lateral mass screws, our quantitative findings support consideration for CPS instrumentation in select patients by experienced surgeons.

A surgeon-controlled mode of robotic assistance with posterolateral approach helps achieve highly medialized cervical pedicle screw placement to avoid vertebral artery injury

PURPOSE

The small pedicle widths, the thin lateral cortical shell next to the vertebral artery (VA), and the strongly tilted pedicle axis anteromedially narrow the safety margin for cervical pedicle screw (CPS) placement against vertebral artery (VA) injury. We have studied whether the minimally invasive surgery (MIS) of a posterolateral approach with a table-mounted, surgeon-controlled mode of robotic assistance (group R) improves the VA safety compared to C-arm fluoroscopy-guided conventional open technique (group F).

METHODS

Group R consisted of 165 screws in 37 patients and group F, 199 screws in 52 patients. The two groups covered a broad range of vertebral levels from C2 to C7 with comparable distribution (p = 0.0512) for treating a similar variety of diseases (p = 0.6958).

RESULTS

Group R, compared with group F, showed a greater lateral-to-medial CPS inclination (p ≤ 0.0004) that even exceeded the obliquity of corresponding pedicle axis, leading to a higher rate of acceptable CPS placement (93.4% vs. 85.4%; p = 0.0164) with a lower rate of lateral breach (1.2% vs. 10.1%; p = 0.0004).

CONCLUSION

For CPS placement, robot-assisted MIS obviously eliminates morbidity-prone soft-tissue dissection, radiation exposure to the surgical team, and human manual errors. The current study revealed its additional benefit of better safety against VA injury by allowing us to place CPS with a steep lateral-to-medial angulation owing to (1) a lack of counter pressure from the paravertebral muscles and (2) minimizing a navigation pitfall of untracked pressure-induced vertebral rotation.

Current status and prospects of robot-assisted spine surgery

INTRODUCTION

Traditional spine surgery is frequently impeded by a number of challenges, including the complexity of the underlying anatomy, the depth of the surgical locations, and the limited visibility. These factors can collectively result in prolonged operation times and a reduction in the precision. The advent of robot-assisted spine surgery has brought about a transformative solution, particularly in the context of screw placement. Robot-assisted spine surgery has the potential to enhance accuracy and safety while minimizing soft tissue damage.

AREAS COVERED

This article presents a review of the current state of robot systems in spine surgery. The principal advantages of robot-assisted technology include high precision in screw placement, robust imaging capabilities, reduced surgeon fatigue, and the potential for remote operation, thereby addressing disparities in healthcare access. Clinical studies indicate that robot-assisted techniques significantly improve the accuracy of screw placement and may reduce the incidence of postoperative complications. Challenges such as cost, technology limitations, and the need for comprehensive clinical guidelines persist.

EXPERT OPINION

It is anticipated that future advancements in surgical navigation, artificial intelligence integration and the expansion of robot functions will further enhance the efficacy of robot-assisted spine surgery, with the potential to improve patient outcomes and facilitate broader adoption in clinical practice.

S8 Navigation system combined with an ultrasonic osteotome for three-dimensional real-time dynamic visualization decompression to reduce postoperative neurological deterioration in thoracic ossification of the ligamentum flavum

BACKGROUND

Posterior laminectomy is a standard treatment for thoracic ossification of the ligamentum flavum (TOLF), but it often leads to neurological deterioration during surgery. This study aimed to reduce iatrogenic neurological deterioration by using an S8 navigation system combined with an ultrasonic osteotome for three-dimensional real-time dynamic visualization decompression.

METHODS

A retrospective analysis was conducted on patients who underwent laminectomy and internal fixation for TOLF in our centre from January 2016 to January 2023. Patients were divided into a visualization group (S8 navigation + ultrasonic bone scalpel) and a control group (ultrasonic bone scalpel) based on the use of three-dimensional real-time dynamic visualization decompression technology. Intraoperative multimodal neuroelectrophysiological monitoring (IONM) was used to collect somatosensory evoked potential and motor evoked potential data. We compared the incidence of intraoperative neurological deterioration indicated by IONM alarms between the two groups. Neurological and motor functions were assessed via the American Spinal Injury Association (ASIA) classification system and the modified Japanese Orthopaedic Association (m-JOA) score for thoracic myelopathy. Follow-ups were conducted at 1, 3, 6, and 12 months postsurgery, and the data from both groups were compared. Other clinical indicators included decompression time per laminectomy segment, intraoperative blood loss, intraoperative dural ossification, hospitalization duration, and drainage tube placement time. We also analysed intraoperative and postoperative complications.

RESULTS

A total of 91 patients with thoracic ossification of the ligamentum flavum were included, with a follow-up period of 12-18 months. The visualization group consisted of 41 patients, and the control group included 50 patients. The incidence of neurological deterioration indicated by IONM in the visualization group (9.8%) was significantly lower than that in the control group (30.0%) (P = 0.014). The immediate postoperative ASIA grade change value ≤ - 1 was lower in the visualization group (9.8%) than in the control group (34.0%) (P = 0.006); A similar trend was observed at the 12 month follow-up (2.4% vs. 20.0%, P = 0.022). The m-JOA scores at 1, 3, 6, and 12 months postsurgery were higher in the visualization group than in the control group (P < 0.05). The visualization group also had shorter lamina decompression times per segment and less intraoperative blood loss (P < 0.05). The incidence of nondural ossification cerebrospinal fluid leakage was lower in the visualization group (2.4%) than in the control group (18.0%) (P = 0.018). Additionally, nerve root injury was lower in the visualization group (0%) than in the control group (10.0%) (P = 0.037). Postoperative CT scans revealed no ossification residue in the visualization group, whereas 7 cases (14.0%) were observed in the control group (P = 0.013).

CONCLUSION

The S8 navigation system combined with an ultrasonic osteotome for three-dimensional real-time dynamic visualization decompression significantly reduces the incidence of intraoperative neurological deterioration, improves postoperative motor function recovery, and reduces decompression time per vertebral segment, intraoperative bleeding, and complications such as cerebrospinal fluid leakage. This technology is safe and reliable and offers a promising option for spinal surgeons in treating thoracic ossification of the ligamentum flavum.

Navigated percutaneous placement of cervical pedicle screws: An anatomical feasibility study

Introduction

Percutaneous cervical pedicle screw placement is challenging due to complex anatomy, and requires navigation support. It is unclear how to ensure navigation accuracy in minimally invasive procedures.

Research question

How accurate is image-guided percutaneous pedicle screw positioning after referencing with only one clamp for the complete subaxial cervical spine?

Materials and methods

In six cadavers, all subaxial cervical pedicles were fitted with screws using a standardized procedure. Briefly, a reference clamp was placed via a small skin incision on spinous process C7. The procedure started from C3 and progressed towards C7, without additional imaging, using one registration for all vertebrae. Screws were placed using a navigated screwdriver. Cone-beam CT was performed at three time-points. Screw position was directly intraoperatively evaluated by the surgeons using a modified classification-from Grade 1 (perfect placement) to Grade 5 (highly inaccurate)-and these data were re-evaluated by two independent radiologists.

Results

In six human specimens, 10 guidewires each were placed bilaterally in C3-C7. One screw (1.7%) was intraoperatively classified as Grade 3, but as Grade 4 in the second assessment. All other screws were classified as Grades 1-2 (89.8%) or 3 (8.5%). Screw placement accuracy was not significantly impacted by distance to the clamp or side selection.

Discussion

In percutaneously navigated screw placement with intraoperative imaging, safe screw placement was possible with a reference clamp on C7. Clinical application of this technique has been limited to individual cases. We also propose a new classification for improving screw accuracy and clinical consequences.

Robotic assistance for upper cervical instrumentation: report on accuracy and safety

PURPOSE

This study aims to evaluate the accuracy and safety of C1 lateral mass and upper cervical pedicle screw placement assisted by the TiRobot II system.

METHODS

Ten patients who underwent cervical spine surgery assisted by the TiRobot II system were included. Screw accuracy was assessed using the Gertzbein-Robbins scale and by comparing the final screw positions with pre-planned trajectories. Deviations in screw tip, tail, and angle were recorded. Clinical data, including symptoms, surgical outcomes, and postoperative follow-up, were collected. Neurological improvement was evaluated using pre- and post-operative mJOA scores, with recovery rates calculated by Hirabayashi's method to assess outcomes 3 months after surgery.

RESULTS

A total of 30 screws were placed in 10 patients. All screws (30/30) were within the clinically acceptable range, with 93.33% (28 screws) classified as Grade A and 6.67% (2 screws) as Grade B. In the sagittal plane, the average tip deviation was 1.82 ± 0.79 mm, tail deviation 1.64 ± 0.60 mm, and angular deviation 1.92 ± 1.39°. In the axial plane, tip deviation was 1.96 ± 0.87 mm, tail deviation 1.92 ± 0.65 mm, and angular deviation 2.01 ± 1.07°. The average surgery time was 318.80 ± 66.07 min, with a mean EBL of 205.00 ± 55.03 mL. Postoperative mJOA scores significantly improved from 8.10 ± 1.97 to 12.60 ± 1.78 (p < 0.05), with a 52 ± 14% recovery rate. All patients showed significant symptom improvement.

CONCLUSION

The TiRobot II system demonstrates the capability to precisely execute pre-planned trajectories and improves the accuracy and safety of C1 lateral mass and upper cervical screw placement.

Comparison of Cervical Pedicle Screw Placement Accuracy With Robotic Guidance System Versus Image Guidance System Using Propensity Score Matching

STUDY DESIGN

A retrospective study.

OBJECTIVE

To compare the accuracy of cervical pedicle screw (CPS) placement using a robotic guidance system (RGS) with that of using an image guidance system (IGS; navigation system) through propensity score matching.

BACKGROUND

The RGS may provide accurate CPS placement, which may outperform IGS. However, no study has directly compared the accuracy of CPS placement with the RGS to that with the IGS.

PATIENTS AND METHODS

We retrospectively reviewed the data of patients who had undergone cervical fusion surgery using CPS with the RGS or IGS. To adjust for potential confounders (patient demographic characteristics, disease etiology, and registration material), propensity score matching was performed, creating robotic guidance (RG) and matched image guidance (IG) groups. The accuracy of CPS placement from C2 to C6, where the vertebral artery runs, was evaluated on postoperative computed tomography images according to the Neo classification (grade 0 to grade 3). Furthermore, the intraoperative CPS revisions and related complications were examined.

RESULTS

Using propensity score matching, 22 patients were included in the RG and matched groups each, and a total of 95 and 105 CPSs, respectively, were included in the analysis. In both the axial and sagittal planes, the clinically acceptable rate (grades 0 + 1) of CPS placement did not differ between the RG and matched IG groups (97.9% vs 94.3% and 95.8% vs 96.2%, respectively). The incidence of CPS revision was similar between the groups (2.1% vs 2.9%), and no CPS-related complications were documented. Meanwhile, the incidence of lateral breach (grades 1 + 2 + 3) was significantly lower in the RG group than in the matched IG group (1.1% vs 7.7%, P = 0.037).

CONCLUSION

The RGS and IGS can equally aid in accurate and safe CPS placement in clinical settings. Nonetheless, RGS can further reduce the lateral breach, compared with IGS.

Level-specific comparison of 3D navigated and robotic arm-guided screw placement: an accuracy assessment of 1210 pedicle screws in lumbar surgery

BACKGROUND CONTEXT

Robotic spine surgery, utilizing 3D imaging and robotic arms, has been shown to improve the accuracy of pedicle screw placement compared to conventional methods, although its superiority remains under debate. There are few studies evaluating the accuracy of 3D navigated versus robotic-guided screw placement across lumbar levels, addressing anatomical challenges to refine surgical strategies and patient safety.

PURPOSE

This study aims to investigate the pedicle screw placement accuracy between 3D navigation and robotic arm-guided systems across distinct lumbar levels.

STUDY DESIGN

A retrospective review of a prospectively collected registry.

PATIENT SAMPLE

Patients undergoing fusion surgery with pedicle screw placement in the prone position, using either via 3D image navigation only or robotic arm guidance.

OUTCOME MEASURE

Radiographical screw accuracy was assessed by the postoperative computed tomography (CT) according to the Gertzbein-Robbins classification, particularly focused on accuracy at different lumbar levels.

METHODS

Accuracy of screw placement in the 3D navigation (Nav group) and robotic arm guidance (Robo group) was compared using Chi-squared test/Fisher's exact test with effect size measured by Cramer's V, both overall and at each specific lumbosacral spinal level.

RESULTS

A total of 321 patients were included (Nav, 157; Robo, 189) and evaluated 1210 screws (Nav, 651; Robo 559). The Robo group demonstrated significantly higher overall accuracy (98.6 vs 93.9%; p<.001, V=0.25). This difference of no breach screw rate was signified the most at the L3 level (No breach screw: Robo 91.3 vs 57.8%, p<.001, V=0.35) followed by L4 (89.6 vs 64.7%, p<.001, V=0.28), and L5 (92.0 vs 74.5%, p<.001, V=0.22). However, screw accuracy at S1 was not significant between the groups (81.1 vs 72.0%, V=0.10).

CONCLUSION

This study highlights the enhanced accuracy of robotic arm-guided systems compared to 3D navigation for pedicle screw placement in lumbar fusion surgeries, especially at the L3, L4, and L5 levels. However, at the S1 level, both systems exhibit similar effectiveness, underscoring the importance of understanding each system's specific advantages for optimization of surgical complications.

Accuracy and clinical characteristics of robot-assisted cervical spine surgery: a systematic review and meta-analysis

PURPOSE

To evaluate the accuracy and feasibility of robot-assisted cervical screw placement and factors that may affect the accuracy.

METHODS

A comprehensive search was made on PubMed, Embase, Cochrane Library, Web of Science, CNKI, and Wanfang Med for the selection of potential eligible literature. The outcomes were evaluated in terms of the relative risk (RR) or standardized mean difference (MD) and corresponding 95% confidence interval (CI). Subgroup analyses of the accuracy of screw placement at different cervical segments and with different screw placement approaches were performed. A comparison was made between robotic navigation and conventional freehand cervical screw placement.

RESULTS

Six comparative cohort studies and five case series studies with 337 patients and 1342 cervical screws were included in this study. The perfect accuracy was 86% (95% CI, 82-89%) and the clinically acceptable rate was 98% (95% CI, 95-99%) in robot-assisted cervical screw placement. The perfect accuracy of robot-assisted C1 lateral mass screw placement was the highest (96%), followed by C6-7 pedicle screw placement (93%) and C2 pedicle screw placement (86%), and the lowest was C3-5 pedicle screw placement (75%). The open approach had a higher perfect accuracy than the percutaneous/intermuscular approach (91% vs 83%). Compared with conventional freehand cervical screw placement, robot-assisted cervical screw placement had a higher accuracy, a lower incidence of perioperative complications, and less intraoperative blood loss.

CONCLUSION

With good collaboration between the operator and the robot, robot-assisted cervical screw placement is accurate and feasible. Robot-assisted cervical screw placement has a promising prospect.

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.

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.

Accurate Placement and Revisions for Cervical Pedicle Screws Placed With or Without Navigation: A Systematic Review and Meta-Analysis

STUDY DESIGN

Systematic review and meta-analysis.

OBJECTIVES

To evaluate the accuracy of placement for cervical pedicle screws with and without the use of spinal navigation.

METHODS

A structured search was conducted in electronic databases without any language or date restrictions. Eligible studies reported the proportion of accurately placed cervical pedicle screws measured on intraoperative or postoperative 3D imaging, and reported whether intraoperative navigation was used during screw placement. Randomized Studies (MINORS) criteria were used to evaluate the methodological quality of how accuracy was assessed for cervical pedicle screws.

RESULTS

After screening and critical appraisal, 4697 cervical pedicle screws from 18 studies were included in the meta-analysis. The pooled proportion for cervical pedicle screws with a breach up to 2 mm was 94% for navigated screws and did not differ from the pooled proportion for non-navigated screws (96%). The pooled proportion for cervical pedicle screws placed completely in the pedicle was 76% for navigated screws and did not differ from the pooled proportion for non-navigated screws (82%). Intraoperative screw reposition rates and screw revision rates as a result of postoperative imaging also did not differ between navigated and non-navigated screw placement.

CONCLUSIONS

This systematic review and meta-analysis found that the use of spinal navigation systems does not significantly improve the accuracy of placement of cervical pedicle screws compared to screws placed without navigation. Future studies evaluating intraoperative navigation for cervical pedicle screw placement should focus on the learning curve, postoperative complications, and the complexity of surgical cases.

Free-hand technique of C7 pedicle screw insertion using a simply defined entry point without fluoroscopic guidance for cervical spondylotic myelopathy patients with C3 to C6 instrumented by lateral mass screws: a retrospective cohort study

BACKGROUND

Nowadays, both lateral mass screw (LMS) and pedicle screw were effective instrumentation for posterior stabilization of cervical spine. This study aims to evaluate the feasibility of a new free-hand technique of C7 pedicle screw insertion without fluoroscopic guidance for cervical spondylotic myelopathy (CSM) patients with C3 to C6 instrumented by lateral mass screws.

METHODS

A total of 53 CSM patients underwent lateral mass screws instrumentation at C3 to C6 levels and pedicle screw instrumentation at C7 level were included. The preoperative 3-dimenional computed tomography (CT) reconstruction images of cervical spine were used to determine 2 different C7 pedicle screw trajectories. Trajectory A passed through the axis of the C7 pedicle while trajectory B selected the midpoint of the base of C7 superior facet as the entry point. All these 53 patients had the C7 pedicle screw inserted through trajectory B by free-hand without fluoroscopic guidance and the postoperative CT images were obtained to evaluate the accuracy of C7 pedicle screw insertion.

RESULTS

Trajectory B had smaller transverse angle, smaller screw length, and smaller screw width but both similar sagittal angle and similar pedicle height when compared with trajectory A. A total of 106 pedicle screws were inserted at C7 through trajectory B and only 8 screws were displaced with the accuracy of screw placement as high as 92.5%.

CONCLUSION

In CSM patients with C3 to C6 instrumented by LMS, using trajectory B for C7 pedicle screw insertion is easy to both identify the entry point and facilitate the rod insertion.

Safety and Accuracy of Robot-Assisted Cervical Screw Placement: A Systematic Review and Meta-Analysis

OBJECTIVE

The purpose of this study was to compare the accuracy and safety of robot-assisted (RA) cervical screw placement with conventional freehand (FH) technique.

METHODS

Computer-based searches were conducted on various databases including PubMed, Embase, Cochrane Library, Web of Science, the China Biology Medicine, the China National Knowledge Infrastructure, and Wanfang Database. Inclusion criteria were studies reporting the use of RA techniques for cervical screw placement and providing data on safety and accuracy outcomes. Primary outcome indicators focused on the accuracy of screw placement, while secondary outcome indicators included operative time, intraoperative blood loss, length of hospital stay, complication rate, and radiation dose. Data from eligible studies were extracted and synthesized using a forest plot analysis.

RESULTS

A total of 312 patients (1233 screws) from 6 studies were included, with 148 patients (47.4% with 567 screws) in the RA group. Perfect screw accuracy, as categorized by Gertzbein-Robbins grade A, was significantly superior with RA surgery compared to FH technique. RA screw implantation significantly reduced complication rates, intraoperative blood loss, length of hospitalization, and radiation dose compared to the conventional FH group. However, there was no statistically significant difference in surgery time between the RA and FH groups.

CONCLUSIONS

RA surgery significantly improves the accuracy of cervical screw insertion and offers potential advantages in terms of reduced complications and blood loss, shorter hospital stays, and decreased radiation exposure. However, the impact on operative time remains uncertain. Further high-quality studies, including large-scale randomized controlled trials, are needed to strengthen the evidence base.

Clinical application of spinal robot in cervical spine surgery: safety and accuracy of posterior pedicle screw placement in comparison with conventional freehand methods

The novel robot-assisted (RA) technique has been utilized increasingly to improve the accuracy of cervical pedicle screw placement. Although the clinical application of the RA technique has been investigated in several case series and comparative studies, the superiority and safety of RA over conventional freehand (FH) methods remain controversial. Meanwhile, the intra-pedicular accuracy of the two methods has not been compared for patients with cervical traumatic conditions. This study aimed to compare the rate and risk factors of intra-pedicular accuracy of RA versus the conventional FH approach for posterior pedicle screw placement in cervical traumatic diseases. A total of 52 patients with cervical traumatic diseases who received cervical screw placement using RA (26 patients) and FH (26 patients) techniques were retrospectively included. The primary outcome was the intra-pedicular accuracy of cervical pedicle screw placement according to the Gertzbin-Robbins scale. Secondary outcome parameters included surgical time, intraoperative blood loss, postoperative drainage, postoperative hospital stay, and complications. Moreover, the risk factors that possibly affected intra-pedicular accuracy were assessed using univariate analyses. Out of 52 screws inserted using the RA method, 43 screws (82.7%) were classified as grade A, with the remaining 7 (13.5%) and 2 (3.8%) screws classified as grades B and C. In the FH cohort, 60.8% of the 79 screws were graded A, with the remaining screws graded B (21, 26.6%), C (8, 10.1%), and D (2, 2.5%). The RA technique showed a significantly higher rate of optimal intra-pedicular accuracy than the FH method (P = 0.008), but there was no significant difference between the two groups in terms of clinically acceptable accuracy (P = 0.161). Besides, the RA technique showed remarkably longer surgery time, less postoperative drainage, shorter postoperative hospital stay, and equivalent intraoperative blood loss and complications than the FH technique. Furthermore, the univariate analyses showed that severe obliquity of the lateral atlantoaxial joint in the coronal plane (P = 0.003) and shorter width of the lateral mass at the inferior margin of the posterior arch (P = 0.014) were risk factors related to the inaccuracy of C1 screw placement. The diagnosis of HRVA (P < 0.001), severe obliquity of the lateral atlantoaxial joint in the coronal plane (P < 0.001), short pedicle width (P < 0.001), and short pedicle height (P < 0.001) were risk factors related to the inaccuracy of C2 screw placement. RA cervical pedicle screw placement was associated with a higher rate of optimal intra-pedicular accuracy to the FH technique for patients with cervical traumatic conditions. The severe obliquity of the lateral atlantoaxial joint in the coronal plane independently contributed to high rates of the inaccuracy of C1 and C2 screw placements. RA pedicle screw placement is safe and useful for cervical traumatic surgery.

Robotics in Cervical Spine Surgery: Feasibility and Safety of Posterior Screw Placement

Objective: Robot-assisted (RA) techniques have been widely investigated in thoracolumbar spine surgery. However, the application of RA methods on cervical spine surgery is rare due to the complex morphology of cervical vertebrae and catastrophic complications. Thus, the feasibility and safety of RA cervical screw placement remain controversial. This study aims to evaluate the feasibility and safety of RA screw placement on cervical spine surgery.Methods: A comprehensive search on PubMed, Cochrane Library, Embase Database, Web of Science, Chinese National Knowledge Databases, and Wanfang Database was performed to select potential eligible studies. Randomized controlled trials (RCTs), comparative cohort studies, and case series reporting the accuracy of cervical screw placement were included. The Cochrane risk of bias criteria and Newcastle-Ottawa Scale criteria were utilized to rate the risk of bias of the included literatures. The primary outcome was the rate of cervical screw placement accuracy with robotic guidance; subgroup analyses based on the screw type and insertion segments were also performed.Results: One RCT, 3 comparative cohort studies, and 3 case series consisting of 160 patients and 719 cervical screws were included in this meta-analysis. The combined outcomes indicated that the rates of optimal and clinically acceptable cervical screw placement accuracy under robotic guidance were 88.0% (95% confidence interval [CI], 84.1%–91.4%; p = 0.073; I² = 47.941%) and 98.4% (95% CI, 96.8%–99.5%; p = 0.167; I² = 35.954%). The subgroup analyses showed that the rate of optimal pedicle screw placement accuracy was 88.2% (95% CI, 83.1%–92.6%; p = 0.057; I² = 53.305%); the rates of optimal screw placement accuracy on C1, C2, and subaxial segments were 96.2% (95% CI, 80.5%–100.0%; p = 0.167; I² = 44.134X%), 89.7% (95% CI, 80.6%–96.6%; p = 0.370; I² = 0.000X%), and 82.6% (95% CI, 70.9%–91.9%; p = 0.057; I² = 65.127X%;), respectively.Conclusion: RA techniques were associated with high rates of optimal and clinically acceptable screw positions. RA cervical screw placement is accurate, safe, and feasible in cervical spine surgery with promising clinical potential.

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.

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.

Review of Prospective Trials for Degenerative Cervical Myelopathy

Degenerative cervical myelopathy (DCM) is the leading cause of spinal cord dysfunction in adults. DCM refers to a collection of degenerative conditions that cause the narrowing of the cervical canal resulting in neurological dysfunction. A lack of high-quality studies and a recent increase in public health awareness has led to numerous prospective studies evaluating DCM. Studies evaluating the efficacy of surgical intervention for DCM can be characterized by the presence (comparative) or absence (noncomparative) of a nonoperative control group. Noncomparative studies predominate due to concerns regarding treatment equipoise. Comparative studies have been limited by methodological issues and have not produced consistent findings. More recent noncomparative studies have established the safety and efficacy of surgical intervention for DCM, including mild myelopathy. The optimal surgical intervention for DCM remains controversial. A recent randomized clinical trial comparing dorsal and ventral techniques found similar improvements in patient-reported physical function at early follow-up. Recent prospective studies have enriched our understanding of DCM and helped guide current treatment recommendations.

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.