Background: The Anatomy of Surgical Exposure (ASE) is a cadaver-based operative surgery simulation course that aims to teach techniques and exposures commonly used in open surgical operations. In this study, we used a validated tool to determine efficacy of assessing skills acquisition in the simulated environment. Our aims were to investigate if the ASE course improves the candidates' surgical performance, and to assess if the validated Objective Structured Assessment of Technical Skill (OSATS) template could be a useful tool for assessing technical skills. Methods: Participants (n = 33) undertook supervised assessment of specific procedures at 10 cadaveric stations over a 2-year period; performance was marked using the OSATS template. This template utilizes a seven-item score to assess general and specific surgical techniques and knowledge using a 5-point Likert scale. Experienced tutors assessed each surgery for each participant; individual and comparative data over the 3-day course was used to provide each participant specific feedback at course completion. Results: Average OSATS scores did not improve significantly over the 3-day OSATS course. There was a significant positive correlation observed between surgical trainees and OSATS total scores (P = 0.001, r = 0.747), number of years of post-graduation, and total OSATS scores (P = 0.001, r = 0.527). Conclusions: Our findings indicate that those on the surgical training pathway and those who had graduated earlier, had an overall higher score than those not yet on surgical training. The template was able to provide on-site specific candidate feedback by the end of the course, identifying areas of improvement of technical surgical skills.