Xavier Soong, Alyssa Rothman, Eric Tolo, Maximillian Soong, N George Kasparyan
Finger fractures are common and potentially disabling. Certain complex injuries, particularly with small fragments and/or open wounds, are not manageable with conventional orthopedic hardware. We created 3D-printed finger fracture fixators using polylactic acid (PLA) and polyethylene terephthalate glycol (PETG). We tested flexion stiffness and lateral stiffness, before and after sterilization for surgical use, and compared them against standard 316L surgical stainless-steel (SSS) wires. Because PLA and PETG are compromised at high temperatures, these were sterilized using hydrogen peroxide gas plasma, while the SSS wires were autoclaved. The PLA fixators demonstrated greater flexion stiffness, and equivalent lateral stiffness, to the SSS wires, both before and after sterilization. The PETG fixators demonstrated inferior flexion stiffness and lateral stiffness to the SSS wires, and these properties worsened with sterilization. The PLA fixator was then applied to a cadaveric hand in static and dynamic configurations, and demonstrated excellent radiolucency for visualization of bone alignment and healing. This novel PLA device secures numerous surgical stainless-steel wires, maintains greater flexion stiffness and equivalent lateral stiffness compared to the wires even after sterilization, allows for static and dynamic fixation with compact, lightweight, and modular radiolucent components, and is both low-cost and customizable on demand, which may benefit under-resourced communities.