The SIGMA3D project, funded by the German Federal Ministry of Education and Research (BMBF) under grant number 16SV8392, ran from 1 March 2020 to 31 August 2023, later extended by six months to accommodate pandemic‑related delays. The consortium brought together experts from orthopaedic technology, clinical medicine, computational modelling, simulation, information technology, materials science, biomechanics, 3‑D scanning and printing, and regulatory testing. The University of Munich’s Klinikum served as the medical partner responsible for clinical oversight, evaluation, and functional validation of the orthoses produced within the project.
The core objective was to create a fully digital value‑creation chain for orthopaedic aids that allows patient‑specific 3‑D modelling, simulation, and additive manufacturing of orthoses. The platform was designed to accept diverse patient data—3‑D scans, photographs, CT images—and to generate CAD/CAM models that could be virtually tested for safety and performance before fabrication. A key innovation was the introduction of an automated safety verification step, where virtual load and functional tests are performed on the digital model to confirm compliance with medical standards. This step had not been available in previous orthopaedic workflows.
During the project, a prototype hand orthosis was developed and subjected to a comprehensive validation programme. The workflow began with patient data acquisition using advanced 3‑D scanning techniques. The University of Munich’s team defined medical requirements for the scanning and measurement procedures and assessed the anatomical accuracy of the resulting patient models. A novel algorithm for scan quality control was developed, enabling comparison of different 3‑D scans and of 3‑D printed models against a reference model. This algorithm can determine whether a printed orthosis meets the required medical standard, providing an objective quality metric that was previously lacking.
The digital process chain was fully documented, covering every step from patient capture to final product. After virtual simulation and safety checks, the orthosis was fabricated using additive manufacturing. The finished device was then evaluated in a gait laboratory, through patient questionnaires, and with mechanical testing. The results confirmed that the digitally designed and manufactured orthosis met clinical performance criteria and was well tolerated by the patient. The project demonstrated that the entire chain—from data acquisition to functional validation—can be performed in a streamlined, patient‑centric manner, offering a safer and more intuitive alternative to conventional orthopaedic production.
The collaboration model emphasized integration of clinical expertise with engineering and computational science. The Klinikum’s role extended beyond clinical testing to shaping the technical requirements and ensuring that the digital platform aligned with existing clinical workflows. The consortium’s interdisciplinary composition enabled rapid iteration of the design and simulation tools, while the BMBF funding supported the development of the platform’s core components and the procurement of necessary hardware and software. The successful creation of a validated digital process chain positions SIGMA3D as a template for future orthopaedic device development, with potential to be offered to orthopaedic hospitals and adapted to other assistive device applications.