Surgical Training and Simulation in MISS

54 Surgical Training and Simulation in MISS

Carolin Melcher, Thana Theofanis, Yusef Mosley, Geoffrey Stricsek, Sertac Kirnaz, and James S. Harrop

Summary

This chapter provides an overview of the integration of minimally invasive spine surgery into a trainee’s surgical education and how simulation plays a vital role in making one proficient with the relevant tools and techniques.

Keywords: simulation surgical education cadaver virtual reality

54.1 Introduction

The use of simulation in surgical training has become an essential part of education, particularly in the highly technical and complex fields of neurosurgical and orthopaedic spine procedures. Although nothing can replace time in the operating room alongside master surgeons, simulation allows for trainees to create a uniform foundation upon which they can build upon.1 This is particularly true in minimally invasive spine surgery (MISS), wherein simulation can more closely mirror the actual procedure.

We recently published our procedural metrics for minimally invasive ULBD in combination with a realistic surgical simulator and demonstrated that “simulators” can be used to improve the skills and confidence of trainees. Surgical simulation may offer an important educational complement to traditional methods of skill acquisition and should be explored further with other MIS techniques.²

A basic example of the utility of simulation in spine is from Ghobrial et al, describing a simulated educational model for cerebrospinal fluid (CSF) leak repair for neurosurgery residents, showing this to be a valuable tool for training, synergistically building both a clinical knowledge base and operative technical skill set.² Chitale et al also demonstrated success with a minimally invasive simulation model for pedicle screw placement, showing improvement in trainees after completing the module.³ Thus, simulation allows for effective learning and, most importantly, repetition—so the trainee can rehearse key steps of various clinical scenarios or operative procedures. Leaders in the field have already begun to describe curricula relying on simulation to master core competencies in neurosurgical training.¹^,⁴

Concurrently, external drivers of today’s health care environment, such as patient satisfaction, quality improvement, and cost-effectiveness, have become leading priorities for hospital administration. Thus, the trend toward less invasive surgeries with faster recovery, particularly in spine, will continue due to improved patient satisfaction, deceased hospital length of stay, and other patient-centric outcomes.

Constructivist approaches to human learning have led to the development of a theory called cognitive apprenticeship. This theory holds that masters of a skill often fail to consider the implicit processes involved in carrying out complex skills when they are teaching novices. To ameliorate these tendencies, cognitive apprenticeships “…are designed to bring these tacit processes into the open, where students can observe, enact, and practice them with help from the teacher…”⁵

So how does one become an expert in MISS?

54.2 Methods

Historically, trainees have developed operative skills through the surgical apprenticeship model, following the adage “see one, do one, and teach one.”⁶ This saying oversimplifies the traditional method of teaching trainees. However, it accentuates the observation period of a particular procedure so that one is expected to be capable of performing that procedure. Further, teaching a colleague how to conduct that procedure is also reduced due to the lack of exposure and understanding of the procedure. Thus, trainees are presently expected to accomplish these tasks through exposure to a high volume of cases rather than specifically designed curricula.⁶^,⁷^,⁸

Meanwhile, opportunities for education through interacting with “real” patients diminish after residency due to issues with exposure, time, and resources. Therefore, developing formal education curricula has gained significant interest, specifically designed to teach new surgical skill sets to fully trained surgeons. These formal and defined curriculum are especially relevant for those adopting MISS techniques in their training or clinical practice⁴^,⁹ (Table 54.1). The top three identified limitations to adopting MISS technology are: the technically challenging aspect of the procedures (both for the surgeon and operating rooom staff), lack of mentoring and tutored training opportunities, and the increased radiation exposure and its potential adverse effect on the patient and surgical team.¹⁰

Table 54.1 Table showing general skills. Material is available and can be integrated according to participant’s knowledge

General skills

Using a microscope

Using an enoscope

Using a burr with an endoscope

Using a drill for MISS

Using 2D and 3D navigation and assistive technologies

Managing a dural tear

Bleeding control

Radiation reduction

Placing a tubular retractor (or retractor)

Abbreviation: MISS, minimally invasive spinal surgery.

54.2.1 Learn by Observing an Experienced MISS Surgeon

In spine surgery, particularly MISS procedures, managing and navigating the sequence of steps during an operative procedure require mastery of all the technically complex maneuvers in addition to understanding how to coordinate these numerous individual components such that they ultimately accomplish the goals of the surgery. Education in the operating room is often an intimate, intense, and complex series of didactics and demonstrations. This includes advising, illustrative hand gestures, supportive physical actions, and repositioning of teaching instruments. Education research has shown that there are usually two general categories of teaching behaviors: surgical actions and teaching gestures.

Surgical actions assist the trainee in completing individual surgical steps of the procedure, which include: retracting, using instruments, and manipulating tissues. Gestures are expressed with the teacher’s hands, fingers, and arms to point at an object, or to illustrate the shape of anatomy.11

54.2.2 Fellowships/Grants

There are numerous opportunities to expand one’s knowledge base in MISS techniques since medical industry and spine educational foundation support these surgical procedures by offering fellowship or grants to support training for surgical programs affiliated to MISS. These postresidency experiences in surgical techniques for orthopaedic and neurological surgeons are designed to familiarize younger surgeons with the principles, indications, planning, techniques, and complications of the MISS procedures. Some noteworthy opportunities are listed below:

1.AO Fellowship Program.

2.Eurospine Observership Grant.

3.NASS Fellowship Connect/NASS International Visiting Surgeon Fellowship.

4.Industry-sponsored MISS Fellowships.

54.2.3 Courses

For established spinal surgeons in practice, there is no standard formula for learning and incorporating new surgical techniques into their practice. Currently available educational methods include: traditional continuing medical education (CME) symposia (1-day courses),¹² instructional videos, mentoring, and comprehensive courses that combine lectures and skills laboratories.

Cadaver

Development of MISS skills in cadaver models provides a valuable opportunity to exercise techniques in a controlled environment where the learning curve can be optimized to enhance proficiency.¹³ The value of cadaveric dissection courses in imparting practical and essential knowledge of anatomic structural relationships in the spine has been clearly established. The human cadavers closely emulate intraoperative environments maximizing the technical aspects; but two limiting factors are the time the cadaver is available and the fact that surgical incidents, such as bleeding and CSF leak, cannot be experienced, minimizing the feedback from the model to the trainee.⁸ Furthermore, human cadaveric models may be even less expensive than animal models and have the advantages of the native human anatomy releationships. The basic training techniques have been shown to be of high value not only for research and development but also for the surgeon’s own clinical experience. Many of the scientific meetings and courses provide the opportunity for hands-on cadaveric teaching courses (Fig. 54.1).

a)NASS (North American Spine Society), AANS (American Academy of Neurological Surgeons), CNS (Congress of Neurological Surgeons), AAOS (American Academy of Orthopaedic Surgeons):

1.Specialty Education & Research Center.

b)NYCMISS

c)EUCMISS (European Course for Minimally Invasive Spine Surgery).

d)AO Foundation.

e)Eurospine.

f)National organizations.

g)Industry-sponsored.

Fig. 54.1 Cadaver lab with two participants per table, with the same number of image intensifiers per station.

Animal

Animal models provide high fidelity training with the ability to reproduce the entire operation procedure and associated techniques in order to prepare and avoid complications. However, the use of living animals is problematic due to ethical concerns, high costs, and the need for specialized facilities to perform the procedures. As large animals provide the most similarity to human anatomy, porcine models are commonly used in surgical training of spine procedures.¹⁴^,¹⁵^,¹⁶

Artificial Bone

There is a wide range of artificial bones available throughout industry, from single to multibone models, fractured, intact, or with foam coverings. In the past several years, these models have become more anatomically accurate, particularly in representing the relationship of the pedicles to the anterior and posterior bony elements of the spine. There have been recent advances in the models with the addition of soft tissue and skin on some models. Some examples include:

a)Sawbone.

b)Synbone:

1.Ammolite.

2.SpineStud.

Simulators

A simulator is a device or model used for training individuals by imitating situations and environments that they will encounter in uncontrolled situations.17 Simulation devices have been used in military and aviation training for years, thus providing prospects to exercise technically demanding skills in a safe and controlled environment.¹⁸^,¹⁹ Advances in simulation training models have gone beyond a single procedural skill set to presently incorporating decision-making, problem solving, and judgment in a complex training environment.²⁰ Overall, simulation-based teaching can be divided into five components: Preparation, Exposure, Progression, Feedback, and Repetition.²¹

A critical aspect of a simulation model is the constant feedback accomplished through debriefing and reflection, which is a unique opportunity to reinforce the core assumptions of adult learning, providing external motivation, and stimulating guided reflection.²²^,²³ Understanding how the experience affects future practice is a crucial step to improve performance.²⁴

Virtual Reality

Many of the general surgery disciplines have incorporated simulation through virtual reality (VR) training models into residency training curriculum, allowing trainees to safely develop surgical proficiency and to practice fine motor skills that are directly applicable in live procedures.²⁵^,²⁶ In recent years, the neurosugical and orthopaedic educational programs have have used this approach through MISS procedures. The MISS training has incorporated VR paradigms for simulation and teaching.²⁷^,²⁸^,²⁹^,³⁰^,³¹

RealSpine

RealSpine/Realists is one industry model that utilizes an artificial wetlab training system for lumbar spinal procedures such as discectomies and decompression. This lumbar spine simulator includes all relevant anatomical structures such as the vertebrae, ligamentum flavum, posterior ligamentous complex (PLC), epidural connective tissue, ligaments, intervertebral disc, and dura mater with spinal nerves (Fig. 54.2 and Fig. 54.3). An impressive feature that differentiates it from other simulation models is the ensemble of different materials that closely mimic reality. The simulator can bleed in a controlled and quantifiable way by a two-point bleeding system for diffuse bleeding in the upper part of the simulator and intralaminar osseous bleeding; while drilling the bone and dissecting the tissues, the surgeon feels as if he or she is operating on a real patient. In addition, the model can serve to train on surgical complications management like CSF leaks, if required. The materials for all anatomical structures are made of specially designed synthetics (i.e., polyurethane, epoxy, silicone, gelatine, and latex). This simulator also includes sensors for the feedback of the pressure and the traction on the nerves in the dura and the CSF pressure.²⁷