Authors: Karl E. Balsara, MD
George M. Ghobrial, MD
Ashwini D. Sharan, MD FACS
James S. Harrop, MD, FACS
Since the inception of surgical training, the education of surgeons has been passed down directly from master to trainee across an operative field. However, there comes a point in that course of education that the instruments must be handed over. The attending surgeon hopes that the trainee has read, studied and observed enough to be able to safely and competently execute the necessary surgical maneuvers. Yet as anyone who has ever tried to learn to swing a golf club can attest, reading, studying and observing cannot confer mastery on the first swing. But while a poorly taken golf swing might be no more than embarrassing, the danger to the patient in the hands of the learning surgeon is significantly higher.
Given these circumstances, the value of a simulated surgical experience that provides a trainee the opportunity to practice the physical maneuvers of surgery without risking harm to the patient is obvious. However, the challenge of incorporating such an experience into surgical training has always been the degree to which the operative circumstances could be mimicked. Spine surgery, with its particularly complex structure and sensitivity of the neural elements, has been especially difficult to simulate with any meaningful accuracy. Due to recent advances in high resolution scanning, three dimensional printing and rapid prototyping, a new generation of simulators has been developed. Drs. James Harrop and Ashwini Sharan, working together with Stryker Spine (Kalamazoo, Michigan) and its subsidiary, Phacon Corporation (Leipzig, Germany), created a simulator for the posterior cervical spine which not only replicated the three dimensional form, but also preserved its texture and structural relationships (Figure 1). Cortical and cancellous bone formations were individually replicated, and within the spinal canal, a pressure-sensitive spinal cord analog that was able to electrically detect and record impact was placed (Figure 2).
This simulator was first deployed at the 2012 meeting of the Congress of Neurological Surgeons with participants taking a focused pre-test followed by a didactic presentation, hands-on training with the simulator, and then a post test. Results were based on both the pre- and post-test scores, as well as an objective structured assessment of technical skills (OSATS) score based on a 1-5 rating of five individual criteria. Seventy-eight percent of participants demonstrated improvement in their written test scores over the course of the individual session, while all participants improved their technical scores (median nine points), validating the model as a teaching experience.
Now, neurosurgical residents at Thomas Jefferson Hospital are pioneering the next step in this educational paradigm, incorporating this and other simulation labs longitudinally into their training process. Each of the residents across post-graduate years 1 to 7 completed both the didactic and technical components of the posterior cervical decompression simulator in addition to a dural repair simulator: the goal of this effort being to correlate improvement in simulator scores with increased technical proficiency both across the program’s classes as a whole and as a baseline measure to track individual improvement. This course also incorporated the didactic and technical components of all CNS simulation courses. Using the CNS Portal, an Internet-based neurosurgical education platform, allowed the residents the ability to take the pre-test as well as the didactic component before arriving for the technical portion. Thus, when they arrived for the course, more time was dedicated to hands-on teaching and technical skills.
Reaction to the simulator lab was favorable among the resident participants. While the more senior residents took to the challenge competitively, most junior residents raved about their first hands-on exposure to a technical step in a surgery which they had never before performed. “I’ll never make that mistake again” said one junior resident who was too aggressive in his drilling while others carefully absorbed individual technical details as minute as how to hold the instruments or efficiently throw a dural suture.
Further developments in the technology will allow for video recording of participant performance, making inter-observer validation of technical scores possible. With a standardized, validated method of objective structured assessment in place, residents can eventually practice techniques with these simulators individually, or even video-record their work for scoring. Ultimately, one can imagine “a future where you’ll have to demonstrate objective technical proficiency on a simulator before we allow you to move on to the real thing.”