A Low-Cost, 3D-Printed Simulator for Basic Arthroscopic Skills: A Validation Study

Abstract The purpose of this study was to validate our simulator using the comprehensive Messick validation framework. We hypothesized that the simulator will demonstrate strong validity evidence, particularly in internal structure, its ability to distinguish between experience levels, and in promoting measurable performance improvements over time. A prospective, single-center validation study was conducted between January and April 2023. Fourteen orthopaedic surgery residents and attending surgeons participated, and they were divided into novice (n = 7) and expert (n = 7) groups. The participants performed five standardized arthroscopic tasks designed to develop visuospatial and manual dexterity skills. Performance was evaluated using a validated scoring system that combined the completion time and error rates. Messick's framework was applied to assess the validity across five domains: content, response processes, internal structure, relations with other variables, and consequences. Internal consistency was measured using Cronbach's α and interrater reliability using the intraclass correlation coefficient (ICC). Content validity was established through expert consensus. Standardized instructions and blinded video analysis ensured the validity of the response process. Internal consistency across exercises was high (α = 0.953; 95% confidence interval [CI] = 0.949–0.974), and interrater reliability was excellent (ICC = 0.98; 95% CI = 0.984–0.988). Experts achieved significantly higher baseline scores (median 316 vs. 244; p < 0.001), fewer errors (49 vs. 133; p < 0.001), and faster completion times (median 81 vs. 122 seconds; p < 0.001) than novices, supporting validity related to other variables. Performance improved significantly in both groups over repeated sessions (experts: median +30 points, IQR = 14.2–60.8; p < 0.001; novices: median +69 points, IQR = 45.2–152; p < 0.001), demonstrating the consequences of testing. This low-cost 3D-printed arthroscopic simulator showed satisfactory evidence from multiple sources of validity, establishing it as an effective, reliable, and reproducible educational tool. Its affordability, portability, and ease of use and maintenance could make it a valuable resource for acquiring basic visuomotor skills in arthroscopy through continuous, repetitive, and structured practice in a safe and controlled environment. Prospective comparative validation study, Level II.