Treatment of acetabular fractures is challenging, not only because of its complicated anatomy but also because of the lack of fitting plates. Personalized titanium alloy plates can be fabricated by selective laser melting (SLM) but the biocompatibility of these three-dimensional printing (3D-printed) plates remains unknown. Plates were manufactured by SLM and their cytocompatibility was assessed by observing the metabolism of L929 fibroblasts incubated with culture medium extracts using a CCK-8 assay and their morphology by light microscopy. Allergenicity was tested using a guinea pig maximization test. In addition, acute systemic toxicity of the 3D-printed plates was determined by injecting extracts from the implants into the tail veins of mice. Finally, the histocompatibility of the plates was investigated by implanting them into the dorsal muscles of rabbits. The in vitro results suggested that cytocompatibility of the 3D-printed plates was similar to that of conventional plates. The in vivo data also demonstrated histocompatibility that was comparable between the two manufacturing techniques. In conclusion, both in vivo and in vitro experiments suggested favorable biocompatibility of 3D-printed titanium alloy plates, indicating that it is a promising option for treatment of acetabular fractures.

ObjectiveThis study was performed to explore the treatment of central dislocation of the femoral head without involvement of the acetabular columns.MethodsPreoperatively, a three-dimensionally printed model of the patient’s pelvis was manufactured according to the patient’s computed tomography data. An all-locking anatomical plate was designed based on the mirror of the ipsilesional semi-pelvis. The fracture was reduced using reduction forceps and femoral traction via the lateral rectus approach. The customized plate was used as a template for reduction of the quadrilateral plate fracture.ResultsReduction and fixation of this patient’s fracture was achieved with a customized all-locking anatomical plate with a propeller shape via the lateral rectus approach.ConclusionsThis report describes an isolated quadrilateral plate fracture with central dislocation of the femoral head without involvement of the columns, which is a rare injury that has not yet been classified. It was effectively treated using a customized all-locking anatomical plate with propeller shape via the lateral rectus approach.