Development and evaluation of engineered 3D printed foams for scoliotic braces

Purpose Scoliotic braces are of a two-part design with a polymer shell and foam padding to provide cushioning through energy absorption and support. The padding is manually added and relies on the experience level of the orthotist, neither the accuracy nor the timeliness in construction of the padding is guaranteed. The purpose of the study was to show that a 3D printed foam may be accurately manufactured, applied in a timely fashion and customized to the needs of the patient. Design/methodology/approach Using only existing commercial 3D printing methods and materials, finite element models were established that predict the mechanical response of the engineered foam and validated in the laboratory. Multiple samples of varying density were printed and tested in the laboratory. Accuracy in the print and repeatability in the mechanical properties were also obtained. Findings The mechanical properties of the engineered foam were found to be within the desired range for a valid padding material. Also, the new material has higher energy absorption characteristics than traditional foam and relatively low hysteresis loss. Practical implications The new engineered 3D printed foam has the capability of providing new quickly manufactured and accurate, customizable solutions. Furthermore, there is no need for future advancements in material or 3D printing methods. Originality/value This is the first application of 3D printing to create a structure for padding of Scoliotic braces. The key design equations relating mechanical properties were established as a function of the material density. This allows for this new material to be implemented in the construction of scoliotic braces.