From cadavers to virtual reality: a carbon footprint analysis of surgical simulation for lumbar spine surgery

Simulation plays a fundamental role in lumbar spine surgery training. While many studies focus on the carbon footprint of surgeries, limited information is available on the environmental impact of surgical training. Today, surgical simulators can be categorized into three groups: biological specimens (cadavers and animal models), synthetic physical simulators (bench-top models, 3D-printed, high-fidelity models), and virtual simulators (screen-based and Virtual Reality (VR) simulators). This study analyzed the carbon footprint of the main simulators available for lumbar spine surgery training.

The hypothesis was that biological and high-fidelity simulators would have the highest environmental impact.

Available simulators were identified through an extensive digital search, and categorized based on their features. Environmental data from manufacturers' websites were used, and the simulators with the most available data were selected to represent each category. For missing data, the Life Cycle Assessment (LCA) methodology was used, following the ISO 14040 standard, with OpenLCA® software. In cases of uncertainty, data were cross-checked with the Base Empreinte® database (ADEME, France). The setting of the study was conducted in Paris, France, in January 2025. The carbon footprint of digital simulators was reported relative to the device's lifetime. Cadavers were included as a reference, using an environmental study on cremation in the city of Paris. Results were expressed in kg CO₂e.

Cadavers had the highest carbon footprint (244.0 ± 48.8 kg CO₂e), followed by porcine models (223.0 ± 44.6 kg CO₂e) and high-fidelity simulators (36.6 ± 7.3 kg CO₂e). The carbon footprints of 3D-printed models and bench-top models were similar, at 8.4 ± 1.7 and 10.5 ± 2.1 kg CO₂e respectively. Screen-based and VR simulators had the lowest footprints, with 0.07 ± 0.01 kg CO₂e per simulation. Simulator production and the sterilization of instruments accounted for the majority of emissions.

Low-carbon-footprint simulators should be favored for early learners, especially for basic procedures and repeated simulations. Virtual training is often perceived as less sustainable due to the use of rare earth materials, but is actually more environmentally friendly because of the unlimited number of simulations and the absence of instrument sterilization. 3D printing enables on-demand production of only the required parts, directly on-site. High-fidelity mannequins should be reserved for advanced users, who can better benefit from their realistic features.

III.