Virtual Reality in Preoperative Planning of Adolescent Idiopathic Scoliosis Surgery Using Google Cardboard

The Role of Minimally Invasive Surgery in Spinal Trauma: A Review of Techniques, Outcomes, and Limitations

Minimally invasive surgery (MIS) has significantly revolutionized spine surgery by reducing morbidity, minimizing tissue damage, and improving postoperative outcomes compared with traditional open surgeries. Although MIS is well-documented for degenerative spine diseases, its full scope and limitations in spine trauma remains underexplored. Thus, this review aims to address this gap by examining relevant literature on the evolution, current practices, and future directions of MIS applications in spinal trauma care. We conducted a PubMed search with keywords including "MIS," "percutaneous pedicle screw," "lateral corpectomy," "anterior thoracoscopic surgery," and "transpsoas/direct lateral approach," both individually and in combination with "thoracolumbar trauma," "cervical trauma," and "spine trauma." After screening abstracts and full-text manuscript review, articles meeting inclusion/exclusion criteria were reviewed including prospective and retrospective case-control studies, case reports, and reviews. Exclusionary criteria included studies not involving traumatic injuries of the thoracolumbar or cervical spine, lack of clinical follow-up, and studies in foreign languages. Based on a literature review of 85 studies, the following manuscript focuses on the indications, complications, current literature, clinical outcomes, future directions, and limitations of MIS in managing thoracolumbar and cervical spine injuries with particular emphasis on percutaneous pedicle screw fixation, lateral thoracic and lumbar corpectomies, anterior thoracoscopic/endoscopic approaches, and treatment algorithms. Although MIS for spinal trauma offers numerous advantages, continuous research and data collection are crucial to developing clear treatment algorithms and improving clinical outcomes. However, the future of MIS in spine trauma care remains promising, with advancements in technology and surgical techniques anticipated to enhance safety, efficacy, and patient satisfaction.

Open Versus Minimally Invasive Spine Surgery in the Treatment of Single-Level Degenerative Lumbar Spondylolisthesis: An AO Spine Global Cross-Sectional Study

OBJECTIVE

This study aims to assess global trends in the use of open surgery versus minimally invasive surgery (MIS) for the treatment of single-level L4-5 degenerative lumbar spondylolisthesis (DLS).

METHODS

A cross-sectional online survey issued by the AO Spine Knowledge Forum Degenerative was conducted among AO Spine members between July and September 2023. Participants were presented with 3 clinical cases of L4-5 grade 1 DLS, each with varying degrees of stenosis and instability. The survey captured surgeon demographics and preferences for open versus MIS approaches. Statistical analysis, including chi-square tests and logistic regression, was performed to explore associations between surgical choices and surgeon demographics.

RESULTS

A total of 943 surgeons responded, with 479 completing the survey. Open surgery was the preferred approach in all 3 cases (58.8%, 57.3%, and 42.4%, respectively), particularly in cases involving central and bilateral foraminal stenosis. MIS was the second most common choice, particularly for unilateral foraminal stenosis with mild instability (38.8%). Surgeons' preferences varied significantly by region, age, and fellowship training, with younger and fellowship-trained surgeons more likely to prefer MIS.

CONCLUSION

The study highlights the continued predominance of open surgery for DLS, especially in complex cases, despite the growing acceptance of MIS. Significant regional and demographic variations in surgical preferences suggest the need for tailored guidelines and standardized training protocols to optimize patient outcomes. Future research should focus on the long-term efficacy of these approaches and the impact of evolving technologies on surgical decision-making.

Using Immersive Virtual Reality to Classify Pediatric Thoracolumbar Spine Injuries

Objective This study aimed to assess the reliability and reproducibility of the AO Spine Thoracolumbar Injury Classification System by using virtual reality (VR). We hypothesized that VR is a highly reliable and reproducible method to classify traumatic spine injuries. Methods VR 3D models were created from CT scans of 26 pediatric patients with thoracolumbar spine injuries. Seven orthopedic trainees were educated on the VR platform and AO Spine Thoracolumbar Injury Classification System. Classifications were summarized by primary class and subclass for both rater readings performed two weeks apart with image order randomized. Intra-observer reproducibility was quantified by Fleiss's kappa (kF) for primary classifications and Krippendorff's alpha (aK) for subclassifications along with 95% confidence intervals (CIs) for each rater and across all raters. Inter-observer reliability was quantified by kF for primary classifications and aK for subclassifications along with 95% CIs across all raters for the first read, the second read, and all reads combined. The interpretations were as follows: 0-0.2: slight; 0.2-0.4: fair; 0.4-0.6: moderate; 0.6-0.8: substantial; and >0.8: almost perfect agreement. Results A total of 364 classifications were submitted by seven raters. Intra-observer reproducibility ranged from moderate (kF=0.55) to almost perfect (kF=0.94) for primary classifications and from substantial (aK=0.68) to almost perfect (aK=0.91) for subclassifications. Reproducibility was substantial across all raters for the primary class (kF=0.71; 95% CI=0.61-9.82) and subclass (aK=0.79; 95% CI=0.69-0.86). Inter-observer reliability was substantial (kF=0.63; 95% CI=0.57-0.69) for the first read, moderate (kF=0.58; 95% CI=0.52-0.64) for the second read, and substantial (kF=0.61; 95% CI=0.56-0.65) for all reads for primary classifications. For subclassifications, inter-observer reliability was substantial (aK=0.74; 95% CI=0.58-0.83) for the first read, second read (aK=0.70; 95% CI=0.53-0.80), and all reads (aK=0.72; 95% CI=0.60-0.79). Conclusions Based on our findings, VR is a reliable and reproducible method for the classification of pediatric spine trauma, besides its ability to function as an educational tool for trainees. Further research is needed to evaluate its application for other spine conditions.

Integrating Augmented Reality in Spine Surgery: Redefining Precision with New Technologies

INTRODUCTION

The integration of augmented reality (AR) in spine surgery marks a significant advancement, enhancing surgical precision and patient outcomes. AR provides immersive, three-dimensional visualizations of anatomical structures, facilitating meticulous planning and execution of spine surgeries. This technology not only improves spatial understanding and real-time navigation during procedures but also aims to reduce surgical invasiveness and operative times. Despite its potential, challenges such as model accuracy, user interface design, and the learning curve for new technology must be addressed. AR's application extends beyond the operating room, offering valuable tools for medical education and improving patient communication and satisfaction.

MATERIAL AND METHODS

A literature review was conducted by searching PubMed and Scopus databases using keywords related to augmented reality in spine surgery, covering publications from January 2020 to January 2024.

RESULTS

In total, 319 articles were identified through the initial search of the databases. After screening titles and abstracts, 11 articles in total were included in the qualitative synthesis.

CONCLUSION

Augmented reality (AR) is becoming a transformative force in spine surgery, enhancing precision, education, and outcomes despite hurdles like technical limitations and integration challenges. AR's immersive visualizations and educational innovations, coupled with its potential synergy with AI and machine learning, indicate a bright future for surgical care. Despite the existing obstacles, AR's impact on improving surgical accuracy and safety marks a significant leap forward in patient treatment and care.

Virtual, Augmented, and Mixed Reality Applications for Surgical Rehearsal, Operative Execution, and Patient Education in Spine Surgery: A Scoping Review

Background and Objectives: Advances in virtual reality (VR), augmented reality (AR), and mixed reality (MR) technologies have resulted in their increased application across many medical specialties. VR's main application has been for teaching and preparatory roles, while AR has been mostly used as a surgical adjunct. The objective of this study is to discuss the various applications and prospects for VR, AR, and MR specifically as they relate to spine surgery. Materials and Methods: A systematic review was conducted to examine the current applications of VR, AR, and MR with a focus on spine surgery. A literature search of two electronic databases (PubMed and Scopus) was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). The study quality was assessed using the MERSQI score for educational research studies, QUACS for cadaveric studies, and the JBI critical appraisal tools for clinical studies. Results: A total of 228 articles were identified in the primary literature review. Following title/abstract screening and full-text review, 46 articles were included in the review. These articles comprised nine studies performed in artificial models, nine cadaveric studies, four clinical case studies, nineteen clinical case series, one clinical case-control study, and four clinical parallel control studies. Teaching applications utilizing holographic overlays are the most intensively studied aspect of AR/VR; the most simulated surgical procedure is pedicle screw placement. Conclusions: VR provides a reproducible and robust medium for surgical training through surgical simulations and for patient education through various platforms. Existing AR/MR platforms enhance the accuracy and precision of spine surgeries and show promise as a surgical adjunct.

Optimizing Surgical Efficiency in Complex Spine Surgery Using Virtual Reality as a Communication Technology to Promote a Shared Mental Model: A Case Series and Review

BACKGROUND AND OBJECTIVES

Virtual reality (VR) is an emerging technology that can be used to promote a shared mental model among a surgical team. We present a case series demonstrating the use of 3-dimensional (3D) VR models to visually communicate procedural steps to a surgical team to promote a common operating objective. We also review the literature on existing uses of VR for preoperative communication and planning in spine surgery.

METHODS

Narrations of 3 to 4-minute walkthroughs were created in a VR visualization platform, converted, and distributed to team members through text and email the night before surgical intervention. A VR huddle was held immediately before the intervention to refine surgical goals. After the intervention, the participating team members' perceptions on the value of the tool were assessed using a survey that used a 5-point Likert scale. MEDLINE, Google Scholar, and Dimensions AI databases were queried from July 2010 to October 2022 to examine existing literature on preoperative VR use to plan spine surgery.

RESULTS

Three illustrative cases are presented with accompanying video. Postoperative survey results demonstrate a positive experience among surgical team members after reviewing preoperative plans created with patient-specific 3D VR models. Respondents felt that preoperative VR video review was "moderately useful" or more useful in improving their understanding of the operational sequence (71%, 5/7), in enhancing their ability to understand their role (86%, 6/7), and in improving the safety or efficiency of the case (86%, 6/7).

CONCLUSION

We present a proof of concept of a novel preoperative communication tool used to create a shared mental model of a common operating objective for surgical team members using narrated 3D VR models. Initial survey results demonstrate positive feedback among respondents. There is a paucity of literature investigating VR technology as a means for preoperative surgical communication in spine surgery.

ETHICS

Institutional review board approval (IRB-300009785) was obtained before this study.

[Translated article] How do I plan adolescent idiopathic scoliosis surgery? Systematization of a preoperative planning method

Preoperative planning is essential in adolescent idiopathic scoliosis (AIS) surgery to determine the fusion levels and to perform the procedure with greater precision and diligence. However, the protocolized performance of such planning is not as widespread among specialists in training. The aim of this article is to describe in detail the preoperative planning method for AIS used in a specialised paediatric and adolescent spine unit of a referral centre, as well as the logistics and the tactics, supported a free semi-automatic digital measurement and planning software. Three representative cases of different vertebral deformities, treated by posterior spinal fusion after preoperative planning according to the method, are shown. This method is highly suitable for the trainee surgeon as it combines the advantages of traditional and modern methods, and is simple, low-cost, accessible, reproducible and with an educational character.

How do I plan adolescent idiopathic scoliosis surgery? Systematization of a preoperative planning method

Preoperative planning is essential in adolescent idiopathic scoliosis (AIS) surgery to determine the fusion levels and to perform the procedure with greater precision and diligence. However, the protocolized performance of such planning is not as widespread among specialists in training. The aim of this article is to describe in detail the preoperative planning method for AIS used in a specialized pediatric and adolescent spine unit of a referral center, as well as the logistics and the tactics, supported a free semi-automatic digital measurement and planning software. Three representative cases of different vertebral deformities, treated by posterior spinal fusion after preoperative planning according to the method, are shown. This method is highly suitable for the trainee surgeon as it combines the advantages of traditional and modern methods, and is simple, low cost, accessible, reproducible and with an educational character.

The three-dimensional coupling mechanism in scoliosis and its consequences for correction

INTRODUCTION

In idiopathic scoliosis, the anterior spinal column has rotated away from the midline and has become longer through unloading and expansion of the intervertebral discs. Theoretically, extension of the spine in the sagittal plane should provide room for this longer anterior spinal column, allowing it to swing back towards the midline in the coronal and axial plane, thus reducing both the Cobb angle and the apical vertebral rotation.

METHODS

In this prospective experimental study, ten patients with primary thoracic adolescent idiopathic scoliosis (AIS) underwent MRI (BoneMRI and cVISTA sequences) in supine as well as in an extended position by placing a broad bolster, supporting both hemi-thoraces, under the scoliotic apex. Differences in T4-T12 kyphosis angle, coronal Cobb angle, vertebral rotation, as well as shape of the intervertebral disc and shape and position of the nucleus pulposus, were analysed and compared between the two positions.

RESULTS

Extension reduced T4-T12 thoracic kyphosis by 10° (p < 0.001), the coronal Cobb angle decreased by 9° (p < 0.001) and vertebral rotation by 4° (p = 0.036). The coronal wedge shape of the disc significantly normalized and the wedged and lateralized nucleus pulposus partially reduced to a more symmetrical position.

CONCLUSION

Simple extension of the scoliotic spine leads to a reduction of the deformity in the coronal and axial plane. The shape of the disc normalizes and the eccentric nucleus pulposus partially moves back to the midline.

Optimizing Surgical Performance Using Preoperative Virtual Reality Planning: A Systematic Review

BACKGROUND

Surgery is often a complex process that requires detailed 3-dimensional anatomical knowledge and rigorous interplay between team members to attain ideal operational efficiency or "flow." Virtual Reality (VR) represents a technology by which to rehearse complex plans and communicate precise steps to a surgical team prior to entering the operating room. The objective of this study was to evaluate the use of VR for preoperative surgical team planning and interdisciplinary communication across all surgical specialties.

METHODS

A systematic review of the literature was performed examining existing research on VR use for preoperative surgical team planning and interdisciplinary communication across all surgical fields in order to optimize surgical efficiency. MEDLINE, SCOPUS, CINAHL databases were searched from inception to July 31, 2022 using standardized search clauses. A qualitative data synthesis was performed with particular attention to preoperative planning, surgical efficiency optimization, and interdisciplinary collaboration/communication techniques determined a priori. Preferred Reporting Items for Systematic Review and Meta-Analysis guidelines were followed. All included studies were appraised for their quality using the Medical Education Research Study Quality Instrument (MERSQI) tool.

RESULTS

One thousand and ninety-three non-duplicated articles with abstract and full text availability were identified. Thirteen articles that examined preoperative VR-based planning techniques for optimization of surgical efficiency and/or interdisciplinary communication fulfilled inclusion and exclusion criteria. These studies had a low-to-medium methodological quality with a MERSQI mean score of 10.04 out of 18 (standard deviation 3.61).

CONCLUSIONS

This review demonstrates that time spent rehearsing and visualizing patient-specific anatomical relationships in VR may improve operative efficiency and communication across multiple surgical specialties.

Virtual and Augmented Reality in Spine Surgery: A Systematic Review

BACKGROUND

Augmented reality (AR) and virtual reality (VR) implementation in spinal surgery has expanded rapidly over the past decade. This systematic review summarizes the use of AR/VR technology in surgical education, preoperative planning, and intraoperative guidance.

METHODS

A search query for AR/VR technology in spine surgery was conducted through PubMed, Embase, and Scopus. After exclusions, 48 studies were included. Included studies were then grouped into relevant subsections. Categorization into subsections yielded 12 surgical training studies, 5 preoperative planning, 24 intraoperative usage, and 10 radiation exposure.

RESULTS

VR-assisted training significantly reduced penetration rates or increased accuracy rates compared to lecture-based groups in 5 studies. Preoperative VR planning significantly influenced surgical recommendations and reduced radiation exposure, operating time, and estimated blood loss. For 3 patient studies, AR-assisted pedicle screw placement accuracy ranged from 95.77% to 100% using the Gertzbein grading scale. Head-mounted display was the most common interface used intraoperatively followed by AR microscope and projector. AR/VR also had applications in tumor resection, vertebroplasty, bone biopsy, and rod bending. Four studies reported significantly reduced radiation exposure in AR group compared to fluoroscopy group.

CONCLUSIONS

AR/VR technologies have the potential to usher in a paradigm shift in spine surgery. However, the current evidence indicates there is still a need for 1) defined quality and technical requirements for AR/VR devices, 2) more intraoperative studies that explore usage outside of pedicle screw placement, and 3) technological advancements to overcome registration errors via the development of an automatic registration method.

Three-dimensional technologies in presurgical planning of bone surgeries: current evidence and future perspectives

BACKGROUND

The recent development of three-dimensional (3D) technologies introduces a novel set of opportunities to the medical field in general, and specifically to surgery. The preoperative phase has proven to be a critical factor in surgical success. Utilization of 3D technologies has the potential to improve preoperative planning and overall surgical outcomes. In this narrative review article, the authors describe existing clinical data pertaining to the current use of 3D printing, virtual reality, and augmented reality in the preoperative phase of bone surgery.

METHODS

The methodology included keyword-based literature search in PubMed and Google Scholar for original articles published between 2014 and 2022. After excluding studies performed in nonbone surgery disciplines, data from 61 studies of five different surgical disciplines were processed to be included in this narrative review.

RESULTS

Among the mentioned technologies, 3D printing is currently the most advanced in terms of clinical use, predominantly creating anatomical models and patient-specific instruments that provide high-quality operative preparation. Virtual reality allows to set a surgical plan and to further simulate the procedure via a 2D screen or head mounted display. Augmented reality is found to be useful for surgical simulation upon 3D printed anatomical models or virtual phantoms.

CONCLUSIONS

Overall, 3D technologies are gradually becoming an integral part of a surgeon's preoperative toolbox, allowing for increased surgical accuracy and reduction of operation time, mainly in complex and unique surgical cases. This may eventually lead to improved surgical outcomes, thereby optimizing the personalized surgical approach.

The Future of Minimally Invasive Spinal Surgery

Strong forces are pushing minimally invasive spinal surgery (MISS) to the forefront of spine care. Less-invasive surgical techniques have been enabled by a variety of technical advances. Despite the promise of MISS, however, several factors, including few training opportunities, perception of a steep learning curve, and high upfront costs, have limited the adoption of these techniques. The "6 T's" is a framework highlighting key factors that must be accounted for to ensure safe and effective MISS as techniques continually evolve. Further, technological advancement in endoscopy, robotics, and augmented/virtual reality is enhancing minimally invasive surgeries to make them even less invasive and safer for patients. The evolution of these new techniques and technologies is driving the future of MISS.

The Last Touched Vertebra on Supine Radiographs Can Be the Optimal Lower Instrumented Vertebra in Adolescent Idiopathic Scoliosis Patients

Objective

To determine whether the last touched vertebra (LTV) on supine radiographs is suitable for the lower instrumented vertebra (LIV) in adolescent idiopathic scoliosis (AIS) correction surgery.

Methods

In total, 57 patients were included in the study following posterior instrumentation and fusion. The average follow-up period was 2.2 years. Patients were classified into 4 groups according to the relationship of the location of LIV, LTV, and the last substantially touched vertebra (LSTV) on upright radiographs and the LTV on supine radiographs. In group 1, the upright LTV and supine LTV were the same. Group 1 was subdivided into group 1A and group 1B according to whether the LTV and LSTV were different or the same, respectively. In group 2, the upright LTV was selected as the LIV, whereas in group 3, the supine LTV was selected as the LIV. The baseline characteristics and the preoperative and postoperative radiographic/clinical outcomes of the groups were analyzed.

Results

No differences were found in the preoperative clinical and radiographic baseline characteristics of the 4 groups except the LIV-central sacral vertical line distance. The immediate, 6-month, 1-year, and 2-year postoperative outcomes were not significantly different among the 4 groups. One patient (4.3%) in group 1A experienced radiographic adding-on without clinical symptoms. No patients underwent revision surgery.

Conclusion

The group in whom the LIV was selected as the LTV on supine x-rays showed similar postoperative radiographic and clinical results to other groups. The LTV on preoperative supine radiographs is acceptable as the LIV in AIS surgery to maximize motion segments.

New Approach to Accelerated Image Annotation by Leveraging Virtual Reality and Cloud Computing

Three-dimensional imaging is at the core of medical imaging and is becoming a standard in biological research. As a result, there is an increasing need to visualize, analyze and interact with data in a natural three-dimensional context. By combining stereoscopy and motion tracking, commercial virtual reality (VR) headsets provide a solution to this critical visualization challenge by allowing users to view volumetric image stacks in a highly intuitive fashion. While optimizing the visualization and interaction process in VR remains an active topic, one of the most pressing issue is how to utilize VR for annotation and analysis of data. Annotating data is often a required step for training machine learning algorithms. For example, enhancing the ability to annotate complex three-dimensional data in biological research as newly acquired data may come in limited quantities. Similarly, medical data annotation is often time-consuming and requires expert knowledge to identify structures of interest correctly. Moreover, simultaneous data analysis and visualization in VR is computationally demanding. Here, we introduce a new procedure to visualize, interact, annotate and analyze data by combining VR with cloud computing. VR is leveraged to provide natural interactions with volumetric representations of experimental imaging data. In parallel, cloud computing performs costly computations to accelerate the data annotation with minimal input required from the user. We demonstrate multiple proof-of-concept applications of our approach on volumetric fluorescent microscopy images of mouse neurons and tumor or organ annotations in medical images.