Innovating Flexor Tendon Repair Training with a Three-dimensional Printed Model

Background: Flexor tendon repair is a technically demanding procedure, with functional outcome directly proportional to skillful execution. A repair must be strong to manage early mobilization and precise to allow for gliding through the tendon sheath. As a result, junior residents face a steep learning curve that may be mitigated by exposure to surgical simulators. Methods: To facilitate flexor tendon repair training, a surgical training device and accompanying instructional video were developed. Simulation workshops were held for junior orthopedic and plastic surgery residents (n = 11). To objectively assess validity of the curriculum, study participants performed cadaveric flexor tendon repairs before and after the workshop. Anonymous recordings of these repairs were graded by two certified hand surgeons. Additionally, a tensometer was used to measure strength of repair. Results: Model realism, educational utility, and overall usefulness rated high: 4.6 +/- 0.52 95% confidence interval (CI) for realism, 4.9 +/- 0.42 95% CI for device, 4.7 +/- 0.96 95% CI for video, and 4.9 +/- 0.66 95% CI overall. Subjective confidence increased after the training session (73% ranked "moderately" or "extremely"). Likewise, scores given by the surgeons grading the repairs improved for overall quality and time of repair (pre: 2.77 +/- 0.61, post: 4.22 +/- 0.56, P= 0.0002). Strength of repair did not change (P = 0.87). Conclusions: The proposed three-dimensional surgical simulator for flexor tendon repair is realistic and useful, with improved surgical technique and improved confidence demonstrated after use. This design can be three-dimensionally printed en masse and provide value to hand surgery training curriculum.