CASE STUDY Investigating Spinal Implants 3D Image-Based Methods for Assessing Performance of Additive Manufactured Spinal Implants “ We’ve seen quite a bit of interest in assessing differences between as-designed and as- manufactured parts. It’s now possible to scan a manufactured item, create a model with Simpleware, and compare it to the original design. We simulate the behavior of the manufactured product and assess whether it will function as originally intended. If it doesn’t, engineers can make corrections to the manufacturing process or adjust the design so the final product meets all expectations. ~Mahesh Kailasam, Advisor at Thornton Tomasetti • Workflow bridges CT, image processing, and FE simulation Spinal fixation is a standard of care for patients who suffer from traumatic and chronic injuries that affect mobility and cause increased pain. Additive manufacturing (AM) provides one solution for patient-specific orthopaedic devices, enabling a wider set of inputs and design choices than traditional production. However, there are still questions about workflow efficiency, quality assurance and the validation of parts. • Analysis of as-manufactured implants reveals deviations from as-designed part • Simulation in SIMULIATM Abaqus enables minimization of functional differences in parts • Proof-of-concept closes design loop from original models to actual parts for clinical applications • Methods effective at handling complex anatomical and CAD data AM particularly creates questions over accuracy, quality, strength, and part reliability, requiring comparison of original designs and as-manufactured parts. 3D imaging technologies like industrial computed tomography (CT) are useful here for allowing comparative evaluation and reverse engineering of parts as computational models to study factors such as porosity and dimensional deviations. These methods were brought together by a range of companies to use Simpleware software and other tools to analyze design deviations in a spinal implant.

3D Image Data Acquisition and Image Processing Finite Element Mesh Generation and Simulation Results 4WEB Medical have developed an FDA-cleared, proprietary Truss Implant TechnologyTM that leverages mechanobiologic mechanisms through a truss design, stimulating an osteogenic response to facilitate spinal fusion and improved joint stability. To do so, a spine implant was manufactured by 4WEB Medical’s 3D printing technology and scanned using a Nikon XT H 225 ST CT system. The 3D voxel data was prepared in Nikon CT Pro 3D software, before being imported to Simpleware software for comprehensive...