Development and Validation of SCFE Percutaneous Pinning Surgical Simulation

Abstract

Background: In situ screw fixation with a single percutaneously placed femoral screw remains widely accepted for femoral head fixation in adolescent patients with slipped capital femoral epiphysis (SCFE). Given the potential risks involved with this procedure, a simulation whereby surgical skills could be refined before entering the operating room may be of benefit to orthopaedic trainees. Methods: We developed a synthetic model for the simulated treatment of SCFE. Five orthopaedic attendings and twenty trainees were recorded performing an in situ percutaneous fixation on the SCFE model. Time, radiation exposure, and final anteroposterior and lateral radiographs of the SCFE model were recorded. After completion, the attendings and trainees answered a Likert-based questionnaire regarding the realism and utility of the simulation, respectively. Two blinded orthopaedic surgeons rated each participant’s skill level based on previously described assessment tools, including a Global Rating Scale (GRS) of technical proficiency and radiographic grading index for screw placement. Performance metrics and survey responses were evaluated for construct validity, face validity, and interrater reliability. Results: The attendings demonstrated superior technical proficiency compared with trainees in terms of higher GRS scores (27.9±1.9 vs. 14.7±5.0, P<0.001) and better radiographic grading of screw placement on lateral views (P=0.019). Similarly, compared with the trainees, the orthopaedic attendings demonstrated shorter operative times (11.0±4.1 vs. 14.7±6.2 min, P=0.035) and less radiation exposure (3.7±1.7 vs. 9.5±5.7 mGy, P=0.037). The interrater reliability was excellent for both the GRS scoring (intraclass correlation coefficient=0.973) and radiographic grading (weighted κ=1.000). The attendings and trainees rated the realism and teaching utility of the simulation as “very good,” respectively. Conclusion: Our surgical simulation for in situ percutaneous fixation of SCFE represents a valid and reliable measure of technical competency and demonstrates much promise for potential use as a formative educational tool for orthopaedic residency programs. Level of Evidence: Level II.