Three-dimensional printing surgical instruments: are we there yet?
BACKGROUND
The applications for rapid prototyping have expanded dramatically over the last 20 y. In recent years, additive manufacturing has been intensely investigated for surgical implants, tissue scaffolds, and organs. There is, however, scant literature to date that has investigated the viability of three-dimensional (3D) printing of surgical instruments.


METHODS
Using a fused deposition modeling printer, an Army/Navy surgical retractor was replicated from polylactic acid (PLA) filament. The retractor was sterilized using standard Food and Drug Administration approved glutaraldehyde protocols, tested for bacteria by polymerase chain reaction, and stressed until fracture to determine if the printed instrument could tolerate force beyond the demands of an operating room (OR).


RESULTS
Printing required roughly 90 min. The instrument tolerated 13.6 kg of tangential force before failure, both before and after exposure to the sterilant. Freshly extruded PLA from the printer was sterile and produced no polymerase chain reaction product. Each instrument weighed 16 g and required only $0.46 of PLA.


CONCLUSIONS
Our estimates place the cost per unit of a 3D-printed retractor to be roughly 1/10th the cost of a stainless steel instrument. The PLA Army/Navy retractor is strong enough for the demands of the OR. Freshly extruded PLA in a clean environment, such as an OR, would produce a sterile ready-to-use instrument. Because of the unprecedented accessibility of 3D printing technology world wide and the cost efficiency of these instruments, there are far reaching implications for surgery in some underserved and less developed parts of the world.
Department of Surgery, University of Arizona, Tucson, Arizona.
Timothy M
TM
Rankin
Department of Surgery, Southern Arizona Limb Salvage Alliance, Tucson, Arizona. Electronic address: ngiovinco@gmail.com.
Nicholas A
NA
Giovinco
Department of Surgery, University of Arizona, Tucson, Arizona.
Daniel J
DJ
Cucher
Department of Surgery, University of Arizona Cancer Center, Tucson, Arizona.
George
G
Watts
Department of Surgery, University of Arizona, Tucson, Arizona; Office of the Senior Vice President of Health Sciences, College of Agriculture and Life Sciences, University of Arizona, Tucson, Arizona.
Bonnie
B
Hurwitz
Department of Surgery, Southern Arizona Limb Salvage Alliance, Tucson, Arizona.
David G
DG
Armstrong
D017076:Computer-Aided Design / Q000639:trends*; D021621:Imaging, Three-Dimensional; D019344:Lactic Acid; D008422:Materials Testing; D011091:Polyesters; D011108:Polymers; D013242:Sterilization; D013525:Surgical Instruments / Q000639:trends*
D011091:Polyesters; D011108:Polymers; D019344:Lactic Acid; C033616:poly(lactide)
3D printing; Additive manufacturing; Instruments; Polylactic acid (PLA); Printing surgical instruments; Surgery