Pedicle screw accuracy in clinical utilization of minimally invasive navigated robot-assisted spine surgery

Hybrid-3D robotic suite in spine and trauma surgery - experiences in 210 patients

BACKGROUND

In modern Hybrid ORs, the synergies of navigation and robotics are assumed to contribute to the optimisation of the treatment in trauma, orthopaedic and spine surgery. Despite promising evidence in the area of navigation and robotics, previous publications have not definitively proven the potential benefits. Therefore, the aim of this retrospective study was to evaluate the potential benefit and clinical outcome of patients treated in a fully equipped 3D-Navigation Hybrid OR.

METHODS

Prospective data was collected (March 2022- March 2024) after implementation of a fully equipped 3D-Navigation Hybrid OR ("Robotic Suite") in the authors level 1 trauma centre. The OR includes a navigation unit, a cone beam CT (CBCT), a robotic arm and mixed reality glasses. Surgeries with different indications of the spine, the pelvis (pelvic ring and acetabulum) and the extremities were performed. Spinal and non-spinal screws were inserted. The collected data was analysed retrospectively. Pedicle screw accuracy was graded according to the Gertzbein and Robbins (GR) classification.

RESULTS

A total of n = 210 patients (118 m:92f) were treated in our 3D-Navigation Hybrid OR, with 1171 screws inserted. Among these patients, 23 patients (11.0%) arrived at the hospital via the trauma room with an average Injury Severity Score (ISS) of 25.7. There were 1035 (88.4%) spinal screws inserted at an accuracy rate of 98.7% (CI95%: 98.1-99.4%; 911 GR-A & 111 GR-B screws). The number of non-spinal screws were 136 (11.6%) with an accuracy rate of 99.3% (CI95%: 97.8-100.0%; 135 correctly placed screws). This resulted in an overall accuracy rate of 98.8% (CI95%: 98.2-99.4%). The robotic arm was used in 152 cases (72.4%), minimally invasive surgery (MIS) was performed in 139 cases (66.2%) and wound infection occurred in 4 cases (1,9%). Overall, no revisions were needed.

CONCLUSION

By extending the scope of application, this study showed that interventions in a fully equipped 3D-Navigation Hybrid OR can be successfully performed not only on the spine, but also on the pelvis and extremities. In trauma, orthopaedics and spinal surgery, navigation and robotics can be used to perform operations with a high degree of precision, increased safety, reduced radiation exposure for the OR-team and a very low complication rate.

Spinal Metastases of the Vertebrae: Three Main Categories of Pain

Oncologic back pain, infection, inflammation, and trauma are the only specific etiologies of chronic low back pain (CLBP) in contrast to most patients who have non-specific CLBP. In oncologic patients developing CLBP, it is critically important to perform further investigation to exclude spinal metastases (SM).The incidence of cancer is increasing, with 15.7-30% developing SM. In the case of symptomatic SM, we can distinguish three main categories: tumor pain; mechanical pain due to instability, with or without pathologic fractures; and metastatic epidural spinal cord compression (MESCC) or radicular compression. Treatment of SM-related pain is dependent on these categories and consists of symptomatic treatment, target therapy to the bone, radiotherapy, systemic oncologic treatment, and surgery. The care for SM is a multidisciplinary concern, with rapid evolutions in all specialties involved. It is of primordial importance to incorporate the knowledge of specialists in all participating disciplines, such as oncology, radiotherapy, and spinal surgery, to determine the adequate treatment to preserve ambulatory function and quality of life while limiting the burden of treatment if possible. Awareness of potential SM is the first and most important step in the treatment of SM-related pain. Early diagnosis and timely treatment could prevent further deterioration. In this review, we explore the pathophysiology and symptomatology of SM and the treatment options for SM-related pain: tumor pain; mechanical pain due to instability, with or without pathologic fractures; and MESCC or radicular compression.

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.

Deformity correction from the convexity of the curve in neuromuscular scoliosis

Background

"Convex Pedicle Screw Technique" reduces the theoretical risk of neurovascular injury. Our aim is to evaluate the efficacy of this technique in patients with neuromuscular scoliosis (NMS).

Methods

Retrospective study of 12 patients who underwent a Convex Pedicle Screw Technique and were diagnosed with NMS. Patients who had undergone previous spinal surgery were excluded. The minimum follow-up required was 24 months. Demographic data, intraoperative data, neurovascular complications and neurophysiological events requiring implant repositioning, as well as pre- and postoperative radiological variables were collected.

Results

Twelve patients diagnosed with NMS underwent surgery. The median operative time was 217 minutes. Mean blood loss was 3.8±1.1 g/dL hemoglobin (Hb). The median postoperative stay was 8.8±4 days. A reduction of the Cobb angle in primary curve of 49.1% (from 52.8°±18° to 26.5°±12.6°; P<0.001) and in secondary curve of 25.2% (from 27.8°±18.9° to 18.3°±13.3°; P=0.10) was achieved. Coronal balance improved by 69.4% (7.5±46.2 vs. 2.3±20.9 mm; P=0.72) and sagittal balance by 75% (from -14.1±71.8 vs. -3.5±48.6 mm; P=0.50). There were no neurovascular complications. There were no intraoperative neurophysiological events requiring implant repositioning, nor during reduction maneuvers. No infections were reported.

Conclusions

The correction of the deformity from convexity in NMS achieves similar results to other techniques, and a very low complication rate.

Efficacy of computer-assisted robotic based clinical training program for spinal oncology education on pedicle screw placement

Pedicle screw placement (PSP) is the fundamental surgical technique that requires high accuracy for novice orthopedists studying spinal oncology education. Therefore, we set forth to establish a computer-assisted robotic navigation training program for novice spinal oncology education. Novice orthopedists were involved in this study to evaluate the feasibility and safety of the computer-assisted robotic navigation (CARN) training program. In this research, trainees were randomly taught by the CARN training program and the traditional training program. We prospectively collected the clinical data of patients with spinal tumors from 1st May 2021 to 1st March 2022. The ability of PSP was evaluated by cumulative sum (CUSUM) analysis, learning curve, and accuracy of pedicle screws. The patients included in both groups had similar baseline characteristics. In the CUSUM analysis of the learning curve for accurate PSP, the turning point in the CARN group was lower than that in the traditional group (70th vs. 92nd pedicle screw). The LC-CUSUM test indicated competency for PSP at the 121st pedicle screw in the CARN group and the 138th pedicle screw in the traditional group. The accuracy of PSP was also significantly higher in the CARN group than in the traditional group (88.17% and 79.55%, P = 0.03 < 0.05). Furthermore, no major complications occurred in either group. We first described CARN in spinal oncology education and indicated the CARN training program as a novel, efficient and safe training program for surgeons.

Robotic-Assisted Spine Surgery: Role in Training the Next Generation of Spine Surgeons

OBJECTIVE

This study aimed to assess the degree of interest in robot-assisted spine surgery (RASS) among residents and to investigate the learning curve for beginners performing robotic surgery.

METHODS

We conducted a survey to assess awareness and interest in RASS among young neurosurgery residents. Subsequently, we offered a hands-on training program using a dummy to educate one resident. After completing the program, the trained resident performed spinal fusion surgery with robotic assistance under the supervision of a mentor. The clinical outcomes and learning curve associated with robotic surgery were then analyzed.

RESULTS

Neurosurgical residents had limited opportunities to participate in spinal surgery during their training. Despite this, there was a significant interest in the emerging field of robotic surgery. A trained resident performed RASS under the supervision of a senior surgeon. A total of 166 screw insertions were attempted in 28 patients, with 2 screws failing due to skiving. According to the Gertzbein-Robbins classification, 85.54% of the screws were rated as grade A, 11.58% as grade B, 0.6% as grade C, and 1.2% as grade D. The clinical acceptance rate was approximately 96.99%, which is comparable to the results reported by senior experts and time per screw statistically significantly decreased as experience was gained.

CONCLUSION

RASS can be performed with high accuracy within a relatively short timeframe, if residents receive adequate training.

Machine Learning in Spine Surgery: A Narrative Review

Artificial intelligence and machine learning (ML) can offer revolutionary advances in their application to the field of spine surgery. Within the past 5 years, novel applications of ML have assisted in surgical decision-making, intraoperative imaging and navigation, and optimization of clinical outcomes. ML has the capacity to address many different clinical needs and improve diagnostic and surgical techniques. This review will discuss current applications of ML in the context of spine surgery by breaking down its implementation preoperatively, intraoperatively, and postoperatively. Ethical considerations to ML and challenges in ML implementation must be addressed to maximally benefit patients, spine surgeons, and the healthcare system. Areas for future research in augmented reality and mixed reality, along with limitations in generalizability and bias, will also be highlighted.

A Single-Center Experience of Robotic-Assisted Spine Surgery in Korea : Analysis of Screw Accuracy, Potential Risk Factor of Screw Malposition and Learning Curve

OBJECTIVE

Recently, robotic-assisted spine surgery (RASS) has been considered a minimally invasive and relatively accurate method. In total, 495 robotic-assisted pedicle screw fixation (RAPSF) procedures were attempted on 100 patients during a 14-month period. The current study aimed to analyze the accuracy, potential risk factors, and learning curve of RAPSF.

METHODS

This retrospective study evaluated the position of RAPSF using the Gertzbein and Robbins scale (GRS). The accuracy was analyzed using the ratio of the clinically acceptable group (GRS grades A and B), the dissatisfying group (GRS grades C, D, and E), and the Surgical Evaluation Assistant program. The RAPSF was divided into the no-breached group (GRS grade A) and breached group (GRS grades B, C, D, and E), and the potential risk factors of RAPSF were evaluated. The learning curve was analyzed by changes in robot-used time per screw and the occurrence tendency of breached and failed screws according to case accumulation.

RESULTS

The clinically acceptable group in RAPSF was 98.12%. In the analysis using the Surgical Evaluation Assistant program, the tip offset was 2.37±1.89 mm, the tail offset was 3.09±1.90 mm, and the angular offset was 3.72°±2.72°. In the analysis of potential risk factors, the difference in screw fixation level (p=0.009) and segmental distance between the tracker and the instrumented level (p=0.001) between the no-breached and breached group were statistically significant, but not for the other factors. The mean difference between the no-breach and breach groups was statistically significant in terms of pedicle width (p<0.001) and tail offset (p=0.042). In the learning curve analysis, the occurrence of breached and failed screws and the robot-used time per screw screws showed a significant decreasing trend.

CONCLUSION

In the current study, RAPSF was highly accurate and the specific potential risk factors were not identified. However, pedicle width was presumed to be related to breached screw. Meanwhile, the robot-used time per screw and the incidence of breached and failed screws decreased with the learning curve.

Decreasing the Pedicle Screw Misplacement Rate in the Thoracic Spine With Robot-guided Navigation

STUDY DESIGN

A retrospective chart review.

OBJECTIVE

The aim of this study was to evaluate the screw accuracy of thoracic pedicle screws placed with a robot-guided navigation system.

SUMMARY OF BACKGROUND DATA

Thoracic pedicles are smaller in diameter than lumbar pedicles, making pedicle screw placement difficult. Misplaced pedicle screws may present complications including decreased construct stability, and increased risks of neurological deficits and blood vessel perforation. There is a dearth of knowledge on thoracic pedicle screw accuracy placed with a robot.

MATERIALS AND METHODS

A retrospective analysis of the robot-assisted placement of thoracic pedicle screws was performed. Preoperative and postoperative computed tomography (CT) scans of the implanted thoracic screws were collected to assess screw placement accuracy, pedicle breadth, and placement deviations. A CT-based Gertzbein and Robbins System was used to classify pedicle screw accuracy in 2 mm increments. A custom image overlay software was used to determine the deviations between the preoperatively planned trajectory of pedicle screws and final placement at screw entry (tail), and tip in addition to the angular deviation.

RESULTS

Seventy-five thoracic pedicle screws were implanted by navigated robotic guidance in 17 patients, only 1.3% (1/75) were repositioned intraoperatively. Average patient age and body mass index were 57.5 years and 25.9 kg/m 2 , respectively, with 52.9% female patients. Surgery diagnoses were degenerative disk disease (47.1%) and adjacent segment disease (17.6%). There were zero complications, with no returns to the operating room. According to the CT-based Gertzbein and Robbins pedicle screw breach classification system, 93.3% (70/75) screws were grade A or B, 6.6% (5/75) were grade C, and 0% were grade D or E. The average deviation from the preoperative plan to actual final placement was 1.8±1.3 mm for the screw tip, 1.6±0.9 mm for the tail, and 2.1±1.5 degrees of angulation.

CONCLUSIONS

The current investigation found a 93.3% accuracy of pedicle screw placement in the thoracic spine. Navigated robot assistance is a useful system for placing screws in the smaller pedicles of the thoracic spine.

LEVEL OF EVIDENCE

Level III-retrospective nonexperimental study.

Revolutionizing orthopedics: a comprehensive review of robot-assisted surgery, clinical outcomes, and the future of patient care

Robotic-assisted orthopedic surgery (RAOS) is revolutionizing the field, offering the potential for increased accuracy and precision and improved patient outcomes. This comprehensive review explores the historical perspective, current robotic systems, advantages and limitations, clinical outcomes, patient satisfaction, future developments, and innovation in RAOS. Based on systematic reviews, meta-analyses, and recent studies, this article highlights the most significant findings and compares RAOS to conventional techniques. As robotic-assisted surgery continues to evolve, clinicians and researchers must stay informed and adapt their practices to provide optimal patient care. Evidence from published studies corroborates these claims, highlighting superior component positioning, decreased incidence of complications, and heightened patient satisfaction. However, challenges such as costs, learning curves, and technical issues must be resolved to fully capitalize on these advantages.

Learning Curves for Robot-Assisted Pedicle Screw Placement: Analysis of Operative Time for 234 Cases

BACKGROUND AND OBJECTIVES

Robot-assisted pedicle screw placement is associated with greater accuracy, reduced radiation, less blood loss, shorter hospital stays, and fewer complications than freehand screw placement. However, it can be associated with longer operative times and an extended training period. We report the initial experience of a surgeon using a robot system at an academic medical center.

METHODS

We retrospectively reviewed all patients undergoing robot-assisted pedicle screw placement at a single tertiary care institution by 1 surgeon from 10/2017 to 05/2022. Linear regression, analysis of variance, and cumulative sum analysis were used to evaluate operative time learning curves. Operative time subanalyses for surgery indication, number of levels, and experience level were performed.

RESULTS

In total, 234 cases were analyzed. A significant 0.19-minute decrease in operative time per case was observed (r = 0.14, P = .03). After 234 operations, this translates to a reduction in 44.5 minutes from the first to last case. A linear relationship was observed between case number and operative time in patients with spondylolisthesis (-0.63 minutes/case, r = 0.41, P < .001), 2-level involvement (-0.35 minutes/case, r = 0.19, P = .05), and 4-or-more-level involvement (-1.29 minutes/case, r = 0.24, P = .05). This resulted in reductions in operative time ranging from 39 minutes to 1.5 hours. Continued reductions in operative time were observed across the learning, experienced, and expert phases, which had mean operative times of 214, 197, and 146 minutes, respectively ( P < .001). General proficiency in robot-assisted surgery was observed after the 20th case. However, 67 cases were required to reach mastery, defined as the inflection point of the cumulative sum curve.

CONCLUSION

This study documents the long-term learning curve of a fellowship-trained spine neurosurgeon. Operative time significantly decreased with more experience. Although gaining comfort with robotic systems may be challenging or require additional training, it can benefit surgeons and patients alike with continued reductions in operative time.

The pedicle screw accuracy using a robotic system and measured by a novel three-dimensional method

Robotics in medicine is associated with precision, accuracy, and replicability. Several robotic systems are used in spine surgery. They are all considered shared-control systems, providing "steady-hand" manipulation instruments. Although numerous studies have testified to the benefits of robotic instrumentations, they must address their true accuracy. Our study used the Mazor system under several situations and compared the spatial accuracy of the pedicle screw (PS) insertion and its planned trajectory. We used two cadaveric specimens with intact spinal structures from C7 to S1. PS planning was performed using the two registration methods (preopCT/C-arm or CT-to-fluoroscopy registration). After planning, the implant spatial orientation was defined based on six anatomic parameters using axial and sagittal CT images. Two surgical open and percutaneous access were used to insert the PS. After that, another CT acquisition was taken. Accuracy was classified into optimal, inaccurate and unacceptable according to the degree of screw deviation from its planning using the same spatial orientation method. Based on the type of spatial deviation, we also classified the PS trajectory into 16 pattern errors. Seven (19%) out of 37 implanted screws were considered unacceptable (deviation distances > 2.0 mm or angulation > 5°), and 14 (38%) were inaccurate (> 0.5 mm and ≤ 2.0 mm or > 2.5° and ≤ 5°). CT-to-fluoroscopy registration was superior to preopCT/C-arm (average deviation in 0.9 mm vs. 1.7 mm, respectively, p < 0.003), and percutaneous was slightly better than open but did not reach significance (1.3 mm vs. 1.7 mm, respectively). Regarding pattern error, the tendency was to have more axial than sagittal shifts. Using a quantitative method to categorize the screw 3D position, only 10.8% of the screws were considered unacceptable. However, with a more rigorous concept of inaccuracy, almost half were non-optimal. We also identified that, unlike some previous results, the O-arm registration delivers more accurate implants than the preopCT/C-arm method.

Advances in artificial intelligence, robotics, augmented and virtual reality in neurosurgery

Neurosurgical practitioners undergo extensive and prolonged training to acquire diverse technical proficiencies, while neurosurgical procedures necessitate a substantial amount of pre-, post-, and intraoperative clinical data acquisition, making decisions, attention, and convalescence. The past decade witnessed an appreciable escalation in the significance of artificial intelligence (AI) in neurosurgery. AI holds significant potential in neurosurgery as it supplements the abilities of neurosurgeons to offer optimal interventional and non-interventional care to patients by improving prognostic and diagnostic outcomes in clinical therapy and assisting neurosurgeons in making decisions while surgical interventions to enhance patient outcomes. Other technologies including augmented reality, robotics, and virtual reality can assist and promote neurosurgical methods as well. Moreover, they play a significant role in generating, processing, as well as storing experimental and clinical data. Also, the usage of these technologies in neurosurgery is able to curtail the number of costs linked with surgical care and extend high-quality health care to a wider populace. This narrative review aims to integrate the results of articles that elucidate the role of the aforementioned technologies in neurosurgery.

A Retrospective Analysis of Pedicle Screw Placement Accuracy Using the ExcelsiusGPS Robotic Guidance System: Case Series

BACKGROUND

Robotic guidance has become widespread in spine surgery. Although the intent is improved screw placement, further system-specific data are required to substantiate this intention for pedicle screws in spinal stabilization constructs.

OBJECTIVE

To determine the accuracy of pedicle screws placed with the aid of a robot in a cohort of patients immediately after the adoption of the robot-assisted surgery technique.

METHODS

A retrospective, Institutional Review Board-approved study was performed on the first 100 patients at a single facility, who had undergone spinal surgeries with the use of robotic techniques. Pedicle screw accuracy was graded using the Gertzbein-Robbins Scale based on pedicle wall breach, with grade A representing 0 mm breach and successive grades increasing breach thresholds by 2 mm increments. Preoperative and postoperative computed tomography scans were also used to assess offsets between the objective plan and true screw placements.

RESULTS

A total of 326 screws were analyzed among 72 patients with sufficient imaging data. Ages ranged from 21 to 84 years. The total accuracy rate based on the Gertzbein-Robbins Scale was 97.5%, and the rate for each grade is as follows: A, 82%; B, 15.5%; C, 1.5%; D, 1%; and E, 0. The average tip offset was 1.9 mm, the average tail offset was 2.0 mm, and the average angular offset was 2.6°.

CONCLUSION

Robotic-assisted surgery allowed for accurate implantation of pedicle screws on immediate adoption of this technique. There were no complications attributable to the robotic technique, and no hardware revisions were required.

Advances in robotics and pediatric spine surgery

PURPOSE OF REVIEW

Robotic-assisted surgical navigation for placement of pedicle screws is one of the most recent technological advancements in spine surgery. Excellent accuracy and reliability results have been documented in the adult population, but adoption of robotic surgical navigation is uncommon in pediatric spinal deformity surgery. Pediatric spinal anatomy and the specific pediatric pathologies present unique challenges to adoption of robotic assisted spinal deformity workflows. The purpose of this article is to review the safety, accuracy and learning curve data for pediatric robotic-assisted surgical navigation as well as to identify "best use" cases and technical tips.

RECENT FINDINGS

Robotic navigation has been demonstrated as a safe, accurate and reliable method to place pedicle screws in pediatric patients with a moderate learning curve. There are no prospective studies comparing robotically assisted pedicle screw placement with other techniques for screw placement, however several recent studies in the pediatric literature have demonstrated high accuracy and safety as well as high reliability. In addition to placement of pediatric pedicle screws in the thoracic and lumbar spine, successful and safe placement of screws in the pelvis and sacrum have also been reported with reported advantages over other techniques in the setting of high-grade spondylolisthesis as well as pelvic fixation utilizing S2-alar iliac (S2AI) screws.

SUMMARY

Early studies have demonstrated that robotically assisted surgical navigation for pedicle screws and pelvic fixation for S2AI screws is safe, accurate, and reliable in the pediatric population with a moderate learning curve.

Robotics in neurosurgery: Current prevalence and future directions

Background:

The first instance of a robotic-assisted surgery occurred in neurosurgery; however, it is now more common in other fields such as urology and gynecology. This study aims to characterize the prevalence of robotic surgery among current neurosurgery programs as well as identify trends in clinical trials pertaining to robotic neurosurgery.

Methods:

Each institution’s website was analyzed for the mention of a robotic neurosurgery program and procedures. The future potential of robotics in neurosurgery was assessed by searching for current clinical trials pertaining to neurosurgical robotic surgery.

Results:

Of the top 100 programs, 30 offer robotic cranial and 40 offer robotic spinal surgery. No significant differences were observed with robotic surgical offerings between geographic regions in the US. Larger programs (faculty size 16 or over) had 20 of the 30 robotic cranial programs (66.6%), whereas 21 of the 40 robotic spinal programs (52.5%) were at larger programs. An initial search of clinical trials revealed 223 studies, of which only 13 pertained to robotic neurosurgery. Spinal fixation was the most common intervention (six studies), followed by Deep Brain Stimulation (DBS, two studies), Cochlear implants (two studies), laser ablation (LITT, one study), and endovascular embolization (one study). Most studies had industry sponsors (9/13 studies), while only five studies had hospital sponsors.

Conclusion:

Robotic neurosurgery is still in its infancy with less than half of the top programs offering robotic procedures. Future directions for robotics in neurosurgery appear to be focused on increased automation of stereotactic procedures such as DBS and LITT and robot-assisted spinal surgery.

Safety and risk factors of TINAVI robot-assisted percutaneous pedicle screw placement in spinal surgery

Objective

To determine the rates and risk factors of pedicle screw placement accuracy and the proximal facet joint violation (FJV) using TINAVI robot-assisted technique.

Methods

Patients with thoracolumbar fractures or degenerative diseases were retrospectively recruited from June 2018 and June 2020. The pedicle penetration and proximal FJV were compared in different instrumental levels to identify the safe and risk segments during insertion. Moreover, the factors were also assessed using univariate and multivariate analyses.

Results

A total of 72 patients with 332 pedicle screws were included in the current study. The optimal and clinically acceptable screw positions were 85.8% and 93.4%. Of the 332 screws concerning the intra-pedicular accuracy, 285 screws (85.8%) were evaluated as Grade A according to the Gertzbein and Robbins scale, with the remaining 25 (7.6%), 10 (3.0%), 6 (1.8%), and 6 screws (1.8%) as Grades B, C, D, and E. Moreover, in terms of the proximal FJV, 255 screws (76.8%) screws were assessed as Grade 0 according to the Babu scale, with the remaining 34 (10.3%), 22 (6.6%), and 21 screws (6.3%) as Grades 1, 2, and 3. Furthermore, the univariate analysis showed significantly higher rate of penetration for patients with age < 61 years old, sex of female, thoracolumbar insertion, shorter distance from skin to insertion point, and smaller facet angle. Meanwhile, the patients with the sex of female, BMI < 25.9, grade I spondylolisthesis, lumbosacral insertion, longer distance from skin to insertion point, and larger facet angle had a significantly higher rate of proximal FJV. The outcomes of multivariate analyses showed that sex of male (adjusted OR 0.320, 95% CI 0.140–0.732; p = 0.007), facet angle ≥ 45° (adjusted OR 0.266, 95% CI 0.090–0.786; p = 0.017), distance from skin to insertion point ≥ 4.5 cm (adjusted OR 0.342, 95% CI 0.134–0.868; p = 0.024), and lumbosacral instrumentation (adjusted OR 0.227, 95% CI 0.091–0.566; p = 0.001) were independently associated with intra-pedicular accuracy; the L5 insertion (adjusted OR 2.020, 95% CI 1.084–3.766; p = 0.027) and facet angle ≥ 45° (adjusted OR 1.839, 95% CI 1.026–3.298; p = 0.041) were independently associated with the proximal FJV.

Conclusion

TINAVI robot-assisted technique was associated with a high rate of pedicle screw placement and a low rate of proximal FJV. This new technique showed a safe and precise performance for pedicle screw placement in spinal surgery. Facet angle ≥ 45° is independently associated with both the intra-pedicular accuracy and proximal FJV.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13018-022-03271-6.

Comparison of three imaging and navigation systems regarding accuracy of pedicle screw placement in a sawbone model

3D-navigated pedicle screw placement is increasingly performed as the accuracy has been shown to be considerably higher compared to fluoroscopy-guidance. While different imaging and navigation devices can be used, there are few studies comparing these under similar conditions. Thus, the objective of this study was to compare the accuracy of two combinations most used in the literature for spinal navigation and a recently approved combination of imaging device and navigation system. With each combination of imaging system and navigation interface, 160 navigated screws were placed percutaneously in spine levels T11-S1 in ten artificial spine models. 470 screws were included in the final evaluation. Two blinded observers classified screw placement according to the Gertzbein Robbins grading system. Grades A and B were considered acceptable and Grades C-E unacceptable. Weighted kappa was used to calculate reliability between the observers. Mean accuracy was 94.9% (149/157) for iCT/Curve, 97.5% (154/158) for C-arm CBCT/Pulse and 89.0% for CBCT/StealthStation (138/155). The differences between the different combinations were not statistically significant except for the comparison of C-arm CBCT/Pulse and CBCT/StealthStation (p = 0.003). Relevant perforations of the medial pedicle wall were only seen in the CBCT group. Weighted interrater reliability was found to be 0.896 for iCT, 0.424 for C-arm CBCT and 0.709 for CBCT. Under quasi-identical conditions, higher screw accuracy was achieved with the combinations iCT/Curve and C-arm CBCT/Pulse compared with CBCT/StealthStation. However, the exact reasons for the difference in accuracy remain unclear. Weighted interrater reliability for Gertzbein Robbins grading was moderate for C-arm CBCT, substantial for CBCT and almost perfect for iCT.

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.

Robot-assisted atlantoaxial fixation: illustrative cases

BACKGROUND

Placing screws in the high cervical spine can be challenging because of the vital anatomical structures located in that region. Precision and accuracy with screw placement is needed. The use of robotics in the cervical spine has been described before; however, here the authors describe the use of a new robotic setup.

OBSERVATIONS

The authors describe 2 cases of robot-assisted placement of C2 pars screws and C1–2 transarticular screws. The operative plans for each patient were as follows: placement of C2 pars screws with C2–4 fusion for hangman’s fracture and placement of C1–2 transarticular screws for degenerative disease. Intraoperative computed tomography (CT) was used to plan and navigate the screws. Postoperative CT showed excellent placement of hardware. Both patients presented for initial postoperative clinic visits with no recurrence of prior symptoms.

LESSONS

Intraoperative robotic assistance with instrumentation of the high cervical spine, particularly C2 pars and C1–2 transarticular screws, may ensure proper screw placement and help avoid injury.

Can Robotic Spine Surgery Become the Standard of Care?

Concerns regarding traditional techniques led to the development of robotic systems to facilitate the safe and accurate placement of pedicle screws. The Mazor Spine Assist was the first robotic spine surgery (RSS) platform to receive US Food and Drug Administration approval in 2004. Since then, there has been a steady increase in the application of RSS with several additional iterations of the Mazor platform and other competing systems receiving approval. As the indications, potential benefits, and utilization of RSS continue to expand, the question naturally arises as to whether RSS will eventually become the standard of care for spine surgery. In this article, we review the available evidence and experience with RSS and discuss the potential for RSS to become the medical standard of care.

Ninety-day complication, revision, and readmission rates for current-generation robot-assisted thoracolumbar spinal fusion surgery: results of a multicenter case series

OBJECTIVE

Robotics is a major area for research and development in spine surgery. The high accuracy of robot-assisted placement of thoracolumbar pedicle screws is documented in the literature. The authors present the largest case series to date evaluating 90-day complication, revision, and readmission rates for robot-assisted spine surgery using the current generation of robotic guidance systems.

METHODS

An analysis of a retrospective, multicenter database of open and minimally invasive thoracolumbar instrumented fusion surgeries using the Mazor X or Mazor X Stealth Edition robotic guidance systems was performed. Patients 18 years of age or older and undergoing primary or revision surgery for degenerative spinal conditions were included. Descriptive statistics were used to calculate rates of malpositioned screws requiring revision, as well as overall complication, revision, and readmission rates within 90 days.

RESULTS

In total, 799 surgical cases (Mazor X: 48.81%; Mazor X Stealth Edition: 51.19%) were evaluated, involving robot-assisted placement of 4838 pedicle screws. The overall intraoperative complication rate was 3.13%. No intraoperative implant-related complications were encountered. Postoperatively, 129 patients suffered a total of 146 complications by 90 days, representing an incidence of 16.1%. The rate of an unrecognized malpositioned screw resulting in a new postoperative radiculopathy requiring revision surgery was 0.63% (5 cases). Medical and pain-related complications unrelated to hardware placement accounted for the bulk of postoperative complications within 90 days. The overall surgical revision rate at 90 days was 6.63% with 7 implant-related revisions, representing an implant-related revision rate of 0.88%. The 90-day readmission rate was 7.13% with 2 implant-related readmissions, representing an implant-related readmission rate of 0.25% of cases.

CONCLUSIONS

The results of this multicenter case series and literature review suggest current-generation robotic guidance systems are associated with low rates of intraoperative and postoperative implant-related complications, revisions, and readmissions at 90 days. Future outcomes-based studies are necessary to evaluate complication, revision, and readmission rates compared to conventional surgery.

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

STUDY DESIGN

Systematic review.

OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Rates and risk factors of intrapedicular accuracy and cranial facet joint violation among robot-assisted, fluoroscopy-guided percutaneous, and freehand techniques in pedicle screw fixation of thoracolumbar fractures: a comparative cohort study

Background

Robot-assisted (RA) technique has been increasingly applied in clinical practice, providing promising outcomes of inserting accuracy and cranial facet joint protection. However, studies comparing this novel method with other assisted methods are rare, and the controversy of the superiority between the insertion techniques remains. Thus, we compare the rates and risk factors of intrapedicular accuracy and cranial facet joint violation (FJV) of RA, fluoroscopy-guided percutaneous (FP), and freehand (FH) techniques in the treatment of thoracolumbar fractures.

Methods

A total of 74 patients with thoracolumbar fractures requiring pedicle screw instruments were retrospectively included and divided into RA, FP, and FH groups from June 2016 to May 2020. The primary outcomes were the intrapedicular accuracy and cranial FJV. The factors that affected the intrapedicular accuracy and cranial FJV were assessed using multivariate analyses.

Results

The optimal intrapedicular accuracy of pedicle screw placement (Grade A) in the RA, FP, and FH groups was 94.3%, 78.2%, and 88.7%, respectively. This finding indicates no significant differences of RA over FH technique (P = 0.062) and FP technique (P = 0.025), but significantly higher accuracies of RA over FP (P < 0.001). In addition, the rates of proximal FJV in RA, FP, and FH groups were 13.9%, 30.8%, and 22.7%, respectively. RA had a significantly greater proportion of intact facet joints than the FP (P = 0.002). However, FP and FH (P = 0.157), as well as RA and FH (P = 0.035) showed significantly similar outcomes with respect to the proximal FJV. The logistic regression analysis showed that FP technique (OR = 3.056) was independently associated with insertion accuracy. Meanwhile, the age (OR = 0.974), pedicle angle (OR = 0.921), moderate facet joint osteoarthritis (OR = 5.584), and severe facet joint osteoarthritis (OR = 11.956) were independently associated with cranial FJV.

Conclusion

RA technique showed a higher rate of intrapedicular accuracy and a lower rate of cranial FJV than FP technique, and similar outcomes to FH technique in terms of intrapedicular accuracy and cranial FJV. RA technique might be a safe method for pedicle screw placement in thoracolumbar surgery.

Level of evidence

3

Robotics for neuroendovascular intervention: Background and primer

The simultaneous growth of robotic-assisted surgery and telemedicine in recent years has only been accelerated by the recent coronavirus disease 2019 pandemic. Robotic assistance for neurovascular intervention has garnered significant interest due to opportunities for tele-stroke models of care for remote underserved areas. Lessons learned from medical robots in interventional cardiology and neurosurgery have contributed to incremental but vital advances in medical robotics despite important limitations. In this article, we discuss robot types and their clinical justification and ethics, as well as a general overview on available robots in thoracic/abdominal surgery, neurosurgery, and cardiac electrophysiology. We conclude with current clinical research in neuroendovascular intervention and a perspective on future directions.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Application of a new percutaneous multi-function pedicle locator in minimally invasive spine surgery

In this study, a new percutaneous multi-function pedicle locator was designed for personalized three-dimensional positioning of a pedicle in minimally invasive spine surgery (MISS) without computer-assisted navigation technology. The proposed locator was used in a number of patients during MISS, and its advantages were analyzed. Based on the position of a pedicle determined by computed tomography (CT) and fluoroscopic images of a patient, 6 lines and 2 distances were used to determine the puncture point of a pedicle screw on skin, while 2 angles were used to indicate the direction of insertion of a pedicle guide needle from the patient's body surface. The results of the proposed locator were compared with those of the conventional freehand technique in MISS. The potential benefits of using the locator included enhanced surgical accuracy, reduced operation time, alleviation of the harmful intra-operative radiation exposure, lower costs, and shortened learning curve for young orthopedists.

Less Invasive Pediatric Spinal Deformity Surgery: The Case for Robotic-Assisted Placement of Pedicle Screws

Introduction: Pediatric spinal deformity involves a complex 3-dimensional (3D) deformity that increases the risk of pedicle screw placement due to the close proximity of neurovascular structures. To increase screw accuracy, improve patient safety, and minimize surgical complications, the placement of pedicle screws is evolving from freehand techniques to computer-assisted navigation and to the introduction of robotic-assisted placement. Purpose: The aim of this review was to review the current literature on the use of robotic navigation in pediatric spinal deformity surgery to provide both an error analysis of these techniques and to provide recommendations to ensure its safe application. Methods: A narrative review was conducted in April 2021 using the MEDLINE (PubMed) database. Studies were included if they were peer-reviewed retrospective or prospective studies, included pediatric patients, included a primary diagnosis of pediatric spine deformity, utilized robotic-assisted spinal surgery techniques, and reported thoracic or lumbar pedicle screw breach rates or pedicle screw malpositioning. Results: In the few studies published on the use of robotic techniques in pediatric spinal deformity surgery, several found associations between the technology and increased rates of screw placement accuracy, reduced rates of breach, and minimal complications. All were retrospective studies. Conclusions: Current literature is of a low level of evidence; nonetheless, the findings suggest the accuracy and safety of robotic-assisted spinal surgery in pediatric pedicle screw placement. The introduction of robotics may drive further advances in less invasive pediatric spinal deformity surgery. Further study is warranted.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

Navigational integrity and maintenance of fidelity of optoelectronic data is the cornerstone of robotic-assisted spinal surgery. Transitioning from controlled laboratory to clinical operative environments requires an increased number of steps in the optoelectronic kinematic chain and error potential. Diligence in planning, fiducial positioning, system registration, and intraoperative workflow have the potential to improve accuracy and decrease disparity between planned and final implant position. The key determining factors limiting navigation resolution accuracy are highlighted by this Cochrane research analysis.

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.

Robotics in spine surgery: A systematic review

Robotic systems to assist with pedicle screw placement have recently emerged in the field of spine surgery. Here, the authors systematically reviewed the literature for evidence of these robotic systems and their utility. Thirty-four studies that reported the use of spinal instrumentation with robotic assistance and met inclusion criteria were identified. The outcome measures gathered included: pedicle screw accuracy, indications for surgery, rates of conversion to an alternative surgical method, radiation exposure, and learning curve. In our search there were five different robotic systems identified. All studies reported accuracy and the most commonly used accuracy grading scale was the Gertzbein Robbins scale (GRS). Accuracy of clinically acceptable pedicle screws, defined as < 2 mm cortical breech, ranged from 80% to 100%. Many studies categorized indications for robotic surgery with the most common being degenerative entities. Some studies reported rates of conversion from robotic assistance to manual instrumentation due to many reasons, with robotic failure as the most common. Radiation exposure data revealed a majority of studies reported less radiation using robotic systems. Studies looking at a learning curve effect with surgeon use of robotic assistance were not consistent across the literature. Robotic systems for assistance in spine surgery have continued to improve and the accuracy of pedicle screw placement remains superior when compared to free-hand technique, however rates of manual conversion are significant. Currently, these systems are successfully employed in various pathological entities where trained spine surgeons can be safe and accurate regardless of robotic training.

Biomechanical design and analysis of auxetic pedicle screw to resist loosening

BACKGROUND

Pedicle screws are widely used in fusion surgery, while screw loosening often occurrs. An auxetic structures based pedicle screw was proposed to improve the bone-screw fixation by radial expansion of the screw body under tensile force to resist pulling out. It was optimized to obtain excellent anti-pullout ability for a particular bone based on the biomechanical interaction between screw and surrounding bone.

METHODS

The screw was designed based on re-entrant unit cells. The mechanical properties of it were adjusted by the wall thickness (t) and re-entrant angle (θ) of the unit cell, and characterized using finite element (FE) method. The designed screws were manufactured using 3D-printing, and Ti6Al4V as the materials. Subsequently, the pullout FE models were established, and verified by pulling the fabricated screws out of Sawbone blocks. The pulling out processes of screws from bone were simulated to explore the optimizing design of the screw.

RESULTS

The mechanical properties of the screw could be adjusted in a wide range. The biomechanical interaction between the screw and bone can affect the anti-pullout performance of the screw. With an identical elastic modulus (E), better auxiticity of the screw, resulted in a better anti-pullout performance; while an appropriate E is the necessary condition for its excellent anti-pullout performance for a particular bone.

CONCLUSION

Appropriate mechanical properties are necessary for the auxetic pedicle screw with excellent screw-bone fixation performance for a particular bone, which can be obtained by rationally designing the wall thickness and re-entrant angle of the unit cells.

Reduction in complication and revision rates for robotic-guided short-segment lumbar fusion surgery: results of a prospective, multi-center study

Studies evaluating robotic guidance in lumbar fusion are limited primarily to evaluation of screw accuracy and perioperative complications. This is the first study to evaluate granular differences in short and long-term complication and revision rate profiles between robotic (RG) fluoroscopic (FG) guidance for minimally invasive short-segment lumbar fusions. A retrospective analysis of a prospective, multi-center database was performed. Complications were subdivided into surgical (further subcategorized into adjacent segment disease, new-onset back pain, radiculopathy, motor-deficit, hardware failure, pseudoarthrosis), wound, and medical complications. Complication and revision rates were compared between RG and FG groups cumulatively at 30, 90 days, and 1 year. 374 RG and 111 FG procedures were performed. RG was associated with an 86.25, 83.20, and 69.42% cumulative reduction in complication rate at 30, 90 days, and 1 year, respectively, compared to FG (p < 0.001). At all follow-up points, new-onset radiculopathy and medical complications were most prevalent in both groups. The greatest reductions in complication rates were seen for new-onset back pain (88.13%; p = 0.001) and wound complications (95.05%; p < 0.001) at 30 days, new-onset motor deficits (90.11%; p = 0.004) and wound complications (85.16%; p < 0.001) at 90 days, and new-onset motor deficits (85.16%; p = 0.002), wound (85.16%; p < 0.001), and medical complications (75.72%; p < 0.001) at 1 year. RG was associated with a 92.58% (p = 0.002) reduction in revision rate at 90 days and a 66.08% (p = 0.026) reduction at 1 year. RG was associated with significant reductions in postoperative complication rates at all follow-up time points and significant reductions in revision rates at 90 days and 1 year.

Evaluation of a new spinal surgical robotic system of Kirschner wire placement for lumbar fusion: A multi-centre, randomised controlled clinical study

BACKGROUND

To introduce a novel robotic system 'Orthbot' that has been developed and tested as a surgical assistant for auto-placement of the K-wire in lumbar fusion.

METHODS

This is a multi-centre, randomized controlled clinical study that includes 56 patients (robot group, RG: 27, free-hand group, FG: 29). Following the pre-operative planning and intra-operative fluoroscopic images, the 'Orthbot' automatically completed registration and K-wire placement under the supervision of the surgeon. Deviation distance (DD) and deviation angle (DA) were used as the primary parameters to evaluate the accuracy of the robotic system.

RESULTS

The average DD was 0.95 ± 0.377 mm and 4.35 ± 2.01 mm, respectively in the RG and FG (p < 0.001). The average DA of the K-wire in the coronal plane and the sagittal plane in X-Ray was respectively 6.80 ± 7.79° and 1.27 ± 2.32° in the RG (p < 0.001), and 22.22 ± 16.85° and 4.57 ± 3.86° in the FG (p < 0.001), which showed a higher accuracy rate in the robotic-assisted cases compared to the free-hand cases.

CONCLUSIONS

The novel robotic system could achieve accurate K-wire insertions as indicated by the radiological results.

Initial intraoperative experience with robotic-assisted pedicle screw placement with stealth navigation in pediatric spine deformity: an evaluation of the first 40 cases

Pedicle screw fixation in pediatric spine surgery has become common practice given the fixation stability and improved curve correction. However, due to proximity to vital structures, accuracy is paramount. Literature has reported accuracy rates from 87.5 to 90% using traditional freehand techniques. This study presents our initial experience with pedicle screw placement using the newest generation of spinal robotics for treatment of pediatric spinal deformity. A cohort of patients, aged 8-21 years, undergoing spinal fusion surgery using robotic-assisted technology was reviewed. Diagnoses, Cobb angles, surgical time, robot time, number of screws placed, and complications were recorded. Accuracy of screw placement was assessed based on analysis of successful screw execution, evaluation screw position using intraoperative fluoroscopy and post-operative radiographs, and clinical evaluation. The average age was 14.5 years. Prevalent diagnoses included idiopathic (65%) and neuromuscular scoliosis (13%). Mean preoperative curve measured 66.8°. The median time for operation was 235 minutes with medians of 8 levels fused and 5 screws placed per patient. Of the 314 screws placed, we recorded a 98.7% accuracy rate. Lateral deviation was the most common cause of malpositioning. Post-operative plain films revealed no grossly misplaced screws. There were no perioperative neurologic deficits or malpositioned screws requiring reoperation. This is the first reported series of navigated spinal robotics used for pedicle screw placement in children. Our clinical success rate was 98.7% and there were no clinically relevant screw related complications. The study shows promising initial results of combined robotic-navigation techniques in pediatric patients.

Novel C-arm based planning spine surgery robot proved in a porcine model and quantitative accuracy assessment methodology

BACKGROUND

We assessed pedicle screw accuracy utilizing a novel navigation-based spine surgery robotic system by comparing planned pathways with placed pathways in a porcine model.

METHODS

We placed three mini screws per vertebra for accuracy evaluation and used a reference frame for registration in four pigs (46 screws in 23 vertebrae). We planned screw paths and performed screw insertion under robot guidance. Using C-arm and CT images, we evaluated accuracy by comparing the 3D distance of the placed screw head/tip from the planned screw head/tip and 3D angular offset.

RESULTS

Mean registration deviation between the preoperative 3D space (C-arm) and postoperative CT scans was 0.475 ± 0.119 mm. The average offset from preoperative plan to final placement was 4.8 ± 2.0 mm from the head (tail), 5.3 ± 2.3 mm from the tip and 3.9 ± 2.4 degrees of angulation.

CONCLUSIONS

Our spine surgery robot showed good accuracy in executing an intended planned trajectory and screw path. This faster and more accurate robotic system will be applied in future studies, first in cadavers and subsequently in the clinical field.

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.

A Clinical Application Study of Mixed Reality Technology Assisted Lumbar Pedicle Screws Implantation

Background

This was a prospective comparative study of mixed reality (MR) technology assisted lumbar pedicle screws placement and traditional lumbar pedicle screws placement.

Material/Methods

Fifty cases of lumbar pedicle screws placement were randomly divided into 2 groups: 25 cases with MR technology in group A, and 25 cases without MR technology in group B. All patients had their scores on the Oswestry disability index (ODI) of low back pain and the visual analog scale (VAS) of the affected lower limb recorded at pre-operation. Blood loss, operative duration, success rate of first penetration by tap, and number of times C-arm fluoroscopy was performed were recorded at intraoperation. The postoperative drainage was recorded. The ODI of low back pain and VAS of the affected lower limb were recorded at 1, 3, and 6 months after operation.

Results

Group A had less bleeding, shorter operation time, higher success rate of first penetration by tap, and fewer times using C-arm fluoroscopy at intraoperation (P<0.05). There was significant difference in ODI scores and VAS scores at 1 mouth after operation (P<0.05). The postoperative drainage of group A was less than group B (P<0.05). The implantation accuracy of group A was higher than group B (P<0.05). The postoperative recovery rate of low back pain of group A was faster than group B (P<0.05).

Conclusions

The safety of spinal surgery and implantation accuracy of pedicle screw fixation system could be increased by MR technology.

Robotic Spine Surgery and Augmented Reality Systems: A State of the Art

Instrumented spine procedures have been performed for decades to treat a wide variety of spinal disorders. New technologies have been employed to obtain a high degree of precision, to minimize risks of damage to neurovascular structures and to diminish harmful exposure of patients and the operative team to ionizing radiations. Robotic spine surgery comprehends 3 major categories: telesurgical robotic systems, robotic-assisted navigation (RAN) and virtual augmented reality (AR) systems, including AR and virtual reality. Telesurgical systems encompass devices that can be operated from a remote command station, allowing to perform surgery via instruments being manipulated by the robot. On the other hand, RAN technologies are characterized by the robotic guidance of surgeon-operated instruments based on real-time imaging. Virtual AR systems are able to show images directly on special visors and screens allowing the surgeon to visualize information about the patient and the procedure (i.e., anatomical landmarks, screw direction and inclination, distance from neurological and vascular structures etc.). The aim of this review is to focus on the current state of the art of robotics and AR in spine surgery and perspectives of these emerging technologies that hold promises for future applications.