Basel, Switzerland — Our ex-vivo biomechanical study has been published in the North American Spine Society Journal (NASSJ), independently confirming what our computational models predicted: patient-specific optimized implants resist subsidence at roughly twice the failure force of off-the-shelf cages.
The study, conducted with human cadaveric specimens in collaboration with ETH Zürich's Laboratory for Orthopaedic Technology, compared OptimalPSI's topology-optimized TLIF implants against standard off-the-shelf cages under controlled mechanical loading. The optimized implants demonstrated approximately two times higher resistance to subsidence, with the difference reaching statistical significance (p = 0.03).
For any computational design technology, the critical question is whether in-silico predictions translate into physical performance. This study answers that question. Together with our 2024 Frontiers in Bioengineering and Biotechnology publication — which showed up to 94% median subsidence risk reduction in computational modeling — the two studies provide converging, peer-reviewed evidence for the optimization approach.
Subsidence disproportionately affects patients with compromised bone quality — the very population that often has the fewest treatment options. A cage that distributes load onto strong bone, away from weak regions, could allow surgeons to confidently offer fusion to patients they might otherwise turn away.
"This publication completes Phase 2 of our validation pathway. The physical data confirms our computational predictions — that is exactly the evidence chain regulators and surgeons need to see."
Dr. Thijs Smit, CEO & Co-Founder
With both validation modules complete, OptimalPSI is advancing toward FDA submission and preparing a limited market release with our early adopter surgeon network. Surgeons interested in clinical collaboration can contact us here.
Reference: Du, X., Smit, T., Rubin, W., Cheruparambil, C., Shah, R., Haschtmann, D., Helgason, B., Ferguson, S. J. (2026). Ex-vivo mechanical evaluation of anatomically and mechanically conforming patient-specific spinal fusion cages designed by full-scale topology optimization. NASSJ, 26, 100890.