Cadaver training module for teaching thoracic pedicle screw placement to residents

Image Guided Interpedicular Screw Placement Simulation System for Training and Skill Evaluation. Proof of Concept

BACKGROUND

The SpineST-01 system is an image-guided vertebrae cannulation training system. During task execution, the computer calculates performance-based metrics displaying different visual perspectives (lateral view, axial view, anteroposterior view) with the position of the instrument inside the vertebra. Finally, a report with the metrics is generated as performance feedback.

METHODS

A training box holds a 3D printed spine section. The computer works with 2 orthogonally disposed cameras, tracking passive markers placed on the instrument. Eight metrics were proposed to evaluate the execution of the surgical task. A preliminary study with 25 participants divided into 3 groups (12 novices, 10 intermediates, and 3 expert) was conducted to determine the feasibility of the system and to evaluate and assess the performance differences of each group using Kruskal-Wallis analysis and Mann-Whitney U analysis. In both analyses, a P value ≤ 0.05 was considered statistically significant.

RESULTS

When comparing experts versus novices and all 3 groups, statistical analysis showed significant differences in 6 of the 8 metrics: axial angle error (°), lateral angle error (°), average speed (mm/second), progress between shots (mm), Time (seconds), and shots. The metrics that did not show any statistically significant difference were time between shots (seconds), and speed between shots (mm/second). Also, the average result comparison placed the experts as the best performance group.

CONCLUSIONS

Initial testing of the SpineST-01 demonstrated potential for the system to practice image-guided cannulation tasks on lumbar vertebrae. Results showed objective differences between experts, intermediates, and novices in the proposed metrics, making this system a feasible option for developing basic navigation system skills without the risk of radiation exposure and objectively evaluating task performance.

Resident Training in Spine Surgery: A Systematic Review of Simulation-Based Educational Models

OBJECTIVE

With the increasing prevalence of spine surgery, ensuring effective resident training is becoming of increasing importance. Training safe, competent surgeons relies heavily on effective teaching of surgical indications and adequate practice to achieve a minimum level of technical proficiency before independent practice. American Council of Graduate Medical Education work-hour restrictions have complicated the latter, forcing programs to identify novel methods of surgical resident training. Simulation-based training is one such method that can be used to complement traditional training. The present review aims to evaluate the educational success of simulation-based models in the spine surgical training of residents.

METHODS

Using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, the PubMed, Web of Science, and Google Scholar databases were systematically screened for English full-text studies examining simulation-based spine training curricula. Studies were categorized based on simulation model class, including animal-cadaveric, human-cadaveric, physical/3-dimensional, and computer-based/virtual reality. Outcomes studied included participant feedback regarding the simulator and competency metrics used to evaluate participant performance.

RESULTS

Seventy-two studies were identified. Simulators displayed high face validity and were useful for spine surgery training. Objective measures used to evaluate procedural performance included implant placement evaluation, procedural time, and technical skill assessment, with numerous simulators demonstrating a learning effect.

CONCLUSIONS

While simulation-based educational models are one potential means of training residents to perform spine surgery, traditional in-person operating room training remains pivotal. To establish the efficacy of simulators, future research should focus on improving study quality by leveraging longitudinal study designs and correlating simulation-based training with clinical outcome measures.

Simulation training to retool practicing orthopedic surgeons is rare

Purpose

Modern surgical practice is continuously changing as technology develops. New techniques are often implemented after a surgeon has made the transition to independent clinical practice. There is therefore a need to 'retool' technical skills. Additionally, practicing surgeons must maintain and develop skills such as leadership, communication, critical thinking, teaching, and mentoring. Our aim was to perform a scoping review to assess the current status of simulation education for practicing Orthopedic Surgeons (OS).

Methods

A 10 year search of PubMed, ERIC, and Web of Science was performed with a medical librarian. Controlled vocabulary Medical Subject Headings terms and natural language were developed with subject matter experts describing simulation, training and OS. Two trained reviewers evaluated all abstracts for inclusion. Exclusion criteria were articles that did not assess simulation education involving practicing OS. Data were extracted from the included full text articles by two reviewers: details of study design, type of participants, type of simulation and role of OS in the educational event.

Results

Initial search identified 1824 articles of which 443 were duplicates, and 1381 articles were further screened. Of these, 1155 were excluded, 226 full text articles were assessed for eligibility and 80 included in analysis. Most were published in the last 6 years and from the United States. The majority (99%) described technical skill simulations (arthroscopy 56%, screw placement 23%, ligament reconstruction 19%). OS were rarely the only learners with 91% studies also having residents participate. OS were the targeted learner in 6% studies. OS provided content validity for 15 (19%) and construct validity in 59 (74%) studies.

Conclusions

Simulation training to educate practicing OS is rare. OS are often used to validate work rather than being the center of an educational endeavor. A refocusing is needed to provide adequate training for practicing surgeons to retool skills as new techniques become available.

Simulation Training in Spine Surgery

Simulated surgery is part of a growing paradigm shift in surgical education as a whole. Various modalities from cadaver models to virtual reality have been developed and studied within the context of surgical education. Simulation training in spine surgery has an immense potential to improve education and ultimately improve patient safety. This is due to the inherent risk of operating the spine and the technical difficulty of modern techniques. Common procedures in the modern orthopaedic armamentarium, such as pedicle screw placement, can be simulated, and proficiency is rapidly achieved before application in patients. Furthermore, complications such as dural tears can be simulated and effectively managed in a safe environment with simulation. New techniques with steeper learning curves, such as minimally invasive techniques, can now be safely simulated. Hence, augmenting surgical education through simulation has great potential to benefit trainees and practicing orthopaedic surgeons in modern spine surgery techniques. Additional work will aim to improve access to such technologies and integrate them into the current orthopaedic training curriculum.

The effect of simulation training on resident proficiency in thoracolumbar pedicle screw placement using computer-assisted navigation

OBJECTIVE

Residency work-hour restrictions necessitate efficient, reproducible training. Simulation training for spinal instrumentation placement shows significant benefit to learners' subjective and objective proficiency. Cadaveric laboratories are most effective but have high cost and low availability. The authors' goal was to create a low-cost, efficient, reproducible spinal instrumentation placement simulation curriculum for neurosurgery and orthopedic surgery residents using synthetic models and 3D computer-assisted navigation, assessing subjective and objective proficiency with placement of thoracolumbar pedicle screws.

METHODS

Fifteen neurosurgery and orthopedic surgery residents participated in a standardized curriculum with lecture followed by two separate sessions of thoracolumbar pedicle screw placement in a synthetic spine model utilizing 3D computer-assisted navigation. Data were collected on premodule experience, time and accuracy of screw placement, and both subjective and objective ratings of proficiency.

RESULTS

Fifteen of 15 residents demonstrated improvement in subjective (Physician Performance Diagnostic Inventory Scale [PPDIS]) and 14 in objective (Objective Structured Assessment of Technical Skills [OSATS]) measures of proficiency in navigated screw placement with utilization of this curriculum (p < 0.001 for both), regardless of the number of cases of previous experience using thoracolumbar spinal instrumentation. Fourteen of 15 residents demonstrated decreased time per screw placement from session 1 to session 2 (p = 0.006). There was no significant difference in pedicle screw accuracy between session 1 and session 2.

CONCLUSIONS

A standardized curriculum using synthetic simulation training for navigated thoracolumbar pedicle screw placement results in significantly improved resident subjective and objective proficiency. Development of a nationwide competency curriculum using simulation training for spinal instrumentation placement should be considered for safe, efficient resident training.

Investigation and Feasibility of Combined 3D Printed Thermoplastic Filament and Polymeric Foam to Simulate the Cortiocancellous Interface of Human Vertebrae

Disorders of the spine are among the most common indications for neurosurgical and orthopedic surgical interventions. Spinal fixation in the form of pedicle screw placement is a common form of instrumentation method in the lower cervical, thoracic, and lumbar spine. A vital principle to understand for the safe and accurate placement of pedicle screws is the palpable difference between the cortical and cancellous bone, both of which have different material properties and compositions. Probing and palpation of the hard cortical bone, also known as the “ventral lamina”, covering the neural elements of the spinal canal during screw placement provides manual feedback to the surgeon, indicating an impending breach if continued directional force is applied. Generally, this practice is learned at the expense of patients in live operating room scenarios. Currently, there is a paucity of human vertebra simulation designs that have been validated based on the in vivo ultrastructure and physical properties of human cortical and cancellous bone. In this study, we examined the feasibility of combining three-dimensionally printed thermoplastic polymers with polymeric foam to replicate both the vertebral corticocancellous interface and surface anatomy for procedural education.

Brunetti's chisels in anterior and posterior rachiotomy

Rachiotomy entails vertebral surgical incision, generally followed by exposure of the spinal cord, and is performed primarily for educational, research, or medicolegal purposes. Over time, several tools have been developed for this procedure, but Lodovico Brunetti designed the first effective prototypes in the mid-nineteenth century. To show the technical details of and the necessary maneuvers to be performed for Brunetti's rachiotomies to succeed, a computer-aided systematic literature review of online databases was performed to identify publications concerning Brunetti's chisels used for rachiotomy. Additional references from the studies and treatises included held in the Historical Section of the Medical Library at the University of Padova were checked manually for pertinent information. The known variants of Brunetti's chisels were reported in detail from the first to the third versions produced and intended for both posterior (first and third prototypes) and anterior (second prototype) vertebral dissection. Further evolution that led to the current commercialized model devoted to posterior use also was described. The models' strengths and weaknesses were assessed, as well as the nature of the changes Brunetti introduced over time and their motivation. In conclusion, these tools could represent an alternative to the use of electric saws, particularly for dissectors who prefer to have greater manual control in incising the vertebrae. Clin. Anat. 33:355-364, 2020. © 2019 Wiley Periodicals, Inc.

Systematic review of the current status of cadaveric simulation for surgical training

Background

There is growing interest in and provision of cadaveric simulation courses for surgical trainees. This is being driven by the need to modernize and improve the efficiency of surgical training within the current challenging training climate. The objective of this systematic review is to describe and evaluate the evidence for cadaveric simulation in postgraduate surgical training.

Methods

A PRISMA‐compliant systematic literature review of studies that prospectively evaluated a cadaveric simulation training intervention for surgical trainees was undertaken. All relevant databases and trial registries were searched to January 2019. Methodological rigour was assessed using the widely validated Medical Education Research Quality Index (MERSQI) tool.

Results

A total of 51 studies were included, involving 2002 surgical trainees across 69 cadaveric training interventions. Of these, 22 assessed the impact of the cadaveric training intervention using only subjective measures, five measured impact by change in learner knowledge, and 23 used objective tools to assess change in learner behaviour after training. Only one study assessed patient outcome and demonstrated transfer of skill from the simulated environment to the workplace. Of the included studies, 67 per cent had weak methodology (MERSQI score less than 10·7).

Conclusion

There is an abundance of relatively low‐quality evidence showing that cadaveric simulation induces short‐term skill acquisition as measured by objective means. There is currently a lack of evidence of skill retention, and of transfer of skills following training into the live operating theatre.

Training in cardiac surgery using human cadavers: Effectiveness of "Silent Teachers"

BACKGROUND

Surgical skills acquisition in cardiac surgery requires consistent and hard practice. Furthermore, training using cadaver is advocated as a means of transferring learned skills to the operating room and recreate surgical situations for trainees to practice and hone their skills. We expose our experience in training for cardiac surgical procedures using human cadavers.

METHODS

From June 2013 to November 2016, we performed 302 cardiac surgical procedures on 50 human cadavers obtained according to the Ivorian laws in force. Cadavers were preserved in 10% formaldehyde and by cryopreservation.

RESULTS

In open heart, cardiac surgical techniques were achieved via sternotomy (n = 24) or via "lid-anterolateral thoracotomy" (n = 2). Pericardotomy (n = 26) and/or pericardiectomy (n = 26) were systematic. Aortic and caval canulations and pulmonary artery control (n = 30) were performed. After cardiotomy and arterial incisions (n = 34), 18 atrial and ventricular septal defects repair, 1 Fontan operation, 1 arterial switch, 11 enlargement procedures of the whole right ventricular outlet and 15 acquired valve heart diseases corrections were performed. In closed-heart surgery, procedures were achieved via sternotomy (n = 7), posterolateral thoracotomy (n = 12), or Marfan retroxiphoid approach (n = 3). Pericardotomy (n = 7) or pericardiectomy (n = 7) were performed. Great vessels dissections and expositions (n = 21) were achieved to perform 4 pulmonary artery bandings, 12 patent ductus arteriosus closures, 3 Waldhausen procedures, 7 Brock Operations, and 2 Blalock-Taussig shunts. In both situations, 29 direct pulmonary arterial, auricular, and ventricular sutures were achieved.

CONCLUSION

Surgical simulation in cadaver models offer an opportunity for trainees to practice their surgical skills before entering operating room.

The Effectiveness of Bioskills Training for Simulated Lumbar Pedicle Screw Placement

STUDY DESIGN

Prospective randomized study.

OBJECTIVES

To define the impact of an inexpensive, user-friendly, and reproducible lumbar pedicle screw instrumentation bioskills training module and evaluation protocol.

METHODS

Participants were randomized to control (n = 9) or intervention (n = 10) groups controlling for level of experience (medical students, junior resident, or senior resident). The intervention group underwent a 20-minute bioskills training module while the control group spent the same time with self-directed study. Pre- and posttest performance was self-reported (Physician Performance Diagnostic Inventory Scale [PPDIS]). Objective outcome scores were obtained from a blinded fellowship-trained attending orthopedic spine surgeon using Objective Structured Assessment of Technical Skills (OSATS) and Objective Pedicle Instrumentation Score metrics. In addition, identification of pedicle breach and breach anatomic location was measured pre- and posttest in lumbar spine models.

RESULTS

The intervention group showed a 30.8% improvement in PPDIS scores, compared with 13.4% for the control group (P = .01). The intervention group demonstrated statistically significant 66% decrease in breaches (P = .001) compared with 28% decrease in the control group (P = .06). Breach identification demonstrated no change in accuracy of the control group (incorrect identification from 32.2% pre- to posttest 35%; P = .71), whereas the intervention group's improvement was statistically significant (42% pre- to posttest 36.5%; P = .0047).

CONCLUSIONS

We conclude that a concise lumbar pedicle screw instrumentation bioskills training session can be a useful educational tool to augment clinical education.

Current Status of Simulation-based Training Tools in Orthopedic Surgery: A Systematic Review

OBJECTIVE

To conduct a systematic review of orthopedic training and assessment simulators with reference to their level of evidence (LoE) and level of recommendation.

DESIGN

Medline and EMBASE library databases were searched for English language articles published between 1980 and 2016, describing orthopedic simulators or validation studies of these models. All studies were assessed for LoE, and each model was subsequently awarded a level of recommendation using a modified Oxford Centre for Evidence-Based Medicine classification, adapted for education.

RESULTS

A total of 76 articles describing orthopedic simulators met the inclusion criteria, 47 of which described at least 1 validation study. The most commonly identified models (n = 34) and validation studies (n = 26) were for knee arthroscopy. Construct validation was the most frequent validation study attempted by authors. In all, 62% (47 of 76) of the simulator studies described arthroscopy simulators, which also contained validation studies with the highest LoE.

CONCLUSIONS

Orthopedic simulators are increasingly being subjected to validation studies, although the LoE of such studies generally remain low. There remains a lack of focus on nontechnical skills and on cost analyses of orthopedic simulators.

A pilot study of the utility of a laboratory-based spinal fixation training program for neurosurgical residents

OBJECTIVE Pedicle and lateral mass screw placement is technically demanding due to complex 3D spinal anatomy that is not easily visualized. Neurosurgical and orthopedic surgery residents must be properly trained in such procedures, which can be associated with significant complications and associated morbidity. Current training in pedicle and lateral mass screw placement involves didactic teaching and supervised placement in the operating room. The objective of this study was to assess whether teaching residents to place pedicle and lateral mass screws using navigation software, combined with practice using cadaveric specimens and Sawbones models, would improve screw placement accuracy. METHODS This was a single-blinded, prospective, randomized pilot study with 8 junior neurosurgical residents and 2 senior medical students with prior neurosurgery exposure. Both the study group and the level of training-matched control group (each group with 4 level of training-matched residents and 1 senior medical student) were exposed to a standardized didactic education regarding spinal anatomy and screw placement techniques. The study group was exposed to an additional pilot program that included a training session using navigation software combined with cadaveric specimens and accessibility to Sawbones models. RESULTS A statistically significant reduction in overall surgical error was observed in the study group compared with the control group (p = 0.04). Analysis by spinal region demonstrated a significant reduction in surgical error in the thoracic and lumbar regions in the study group compared with controls (p = 0.02 and p = 0.04, respectively). The study group also was observed to place screws more optimally in the cervical, thoracic, and lumbar regions (p = 0.02, p = 0.04, and p = 0.04, respectively). CONCLUSIONS Surgical resident education in pedicle and lateral mass screw placement is a priority for training programs. This study demonstrated that compared with a didactic-only training model, using navigation simulation with cadavers and Sawbones models significantly reduced the number of screw placement errors in a laboratory setting.

Surgical training using three-dimensional simulation in placement of cervical lateral mass screws: a blinded randomized control trial

BACKGROUND CONTEXT

The skills and knowledge that residents have to master has increased, yet the amount of hours that the residents are allowed to work has been reduced. There is a strong need to improve training techniques to compensate for these changes. One approach is to use simulation-training methods to shorten the learning curve for surgeons in training.

PURPOSE

To analyze the effect of surgical training using three-dimensional (3D) simulation on the placement of lateral mass screws in the cervical spine on either cadavers or sawbones.

STUDY DESIGN

A blinded randomized control study.

METHODS

Fifteen orthopedic residents, postgraduate year (PGY) 1 to 6, were asked to simulate Magerl lateral mass screw trajectories from C3-C7 on cadavers using a navigated drill guide, but with no feedback as to the actual trajectory within the bone (Baseline 1). This was repeated to determine baseline accuracy (Baseline 2). They were then randomized into three groups: Group 1, control, did not receive any training, whereas Groups 2 and 3 received 3D navigational feedback as to the intended drill trajectory on sawbones and cadavers, respectively. All three groups then performed final simulated drilling (final test). All 3D images were deidentified and reviewed by a blinded single fellowship-trained orthopedic spine surgeon. Each image/screw was measured for the starting site, caudad/cephalad angle, and medial/lateral angle to determine trajectory accuracy.

RESULTS

The aggregate mean difference from a perfect screw was compiled for each session for each group. A negative difference shows improvement, whereas a positive difference shows regression. The difference between final test and Baseline 1 in the control group was 2.4°, suggesting regression. In contrast, the differences for groups sawbone and cadaver were -8.2° and -7.2°, respectively, suggesting improvement. When comparing the difference in aggregate sum angle for the sawbones and cadaver groups with the control group, the difference was statistically significant (p<.0001).

CONCLUSIONS

Training with 3D navigation significantly improved the ability of orthopedic residents to properly drill simulated lateral mass screws. As such, training with 3D navigation may be a useful adjunct in resident surgical education.

Virtual reality spine surgery simulation: an empirical study of its usefulness

OBJECTIVE

This study explores the usefulness of virtual simulation training for learning to place pedicle screws in the lumbar spine.

METHODS

Twenty-six senior medical students anonymously participated and were randomized into two groups (A = no simulation; B = simulation). Both groups were given 15 minutes to place two pedicle screws in a sawbones model. Students in Group A underwent traditional visual/verbal instruction whereas students in Group B underwent training on pedicle screw placement in the ImmersiveTouch simulator. The students in both groups then placed two pedicle screws each in a lumbar sawbones models that underwent triplanar thin slice computerized tomography and subsequent analysis based on coronal entry point, axial and sagittal deviations, length error, and pedicle breach. The average number of errors per screw was calculated for each group. Semi-parametric regression analysis for clustered data was used with generalized estimating equations accommodating a negative binomial distribution to determine any statistical difference of significance.

RESULTS

A total of 52 pedicle screws were analyzed. The reduction in the average number of errors per screw after a single session of simulation training was 53.7% (P  =  0.0067). The average number of errors per screw in the simulation group was 0.96 versus 2.08 in the non-simulation group. The simulation group outperformed the non-simulation group in all variables measured. The three most benefited measured variables were length error (86.7%), coronal error (71.4%), and pedicle breach (66.7%).

CONCLUSIONS

Computer-based simulation appears to be a valuable teaching tool for non-experts in a highly technical procedural task such as pedicle screw placement that involves sequential learning, depth perception, and understanding triplanar anatomy.

The role of simulation in developing surgical skills

Surgical training has followed the master-apprentice model for centuries but is currently undergoing a paradigm shift. The traditional model is inefficient with no guarantee of case mix, quality, or quantity. There is a growing focus on competency-based medical education in response to restrictions on doctors' working hours and the traditional mantra of "see one, do one, teach one" is being increasingly questioned. The medical profession is subject to more scrutiny than ever before and is facing mounting financial, clinical, and political pressures. Simulation may be a means of addressing these challenges. It provides a way for trainees to practice technical tasks in a protected environment without putting patients at risk and helps to shorten the learning curve. The evidence for simulation-based training in orthopedic surgery using synthetic models, cadavers, and virtual reality simulators is constantly developing, though further work is needed to ensure the transfer of skills to the operating theatre.