Custom software for the 3D printing of patient specific plate bending templates in pelvic fracture repair.

Abstract

The purpose of this work is to reduce the operative time and blood loss incurred during open reduction and internal fixation (ORIF) of traumatic pelvic injuries through the creation of patient specific bending templates for reconstruction plates. These templates are 3D printed in a resin capable of being sterilized and taken into the operating room so that bending may be performed by the surgeon before the patient is opened or by another team member in parallel with the surgeon. A novel software extension was created in 3D modeling software to allow a surgeon to individually position screws on a pelvic model to create a virtual plate. The software constrains the locations of placed screws so that the virtual plate is dimensionally identical to common reconstruction plates. The user is then able to export a bending template that includes the section of the pelvis the virtual plate was located on as well as screw location landmarks. The user can then flash sterilize the template and use it intraoperatively to obtain a plate that is accurately bent to the patient’s anatomy and the surgeon’s specifications. We produced a bending template representative of the most complex plating location on the pelvis, the posterior wall. A surgeon then accurately bent reconstruction plate to match the bending template, proving that the software produced a dimensionally accurate output. Other work has shown that the pre-bending of plates can shorten operative time, reduce blood loss, and allow for less invasive procedures. However, methods currently available for pre-bending patient specific plates involve the lengthy process of printing the patient’s pelvis and then a lengthy sterilization process of the implant itself. Our method allows the template to be printed and processed in as little as 3 hours and sterilized by autoclave in less than 10 minutes. Further work needs to be done to evaluate how the process works when used in a patient case, to statistically prove that our method reduces operative time and blood loss, and show that plates bent using our method are similar between all members of the surgical team