Banca de DEFESA: JULIO ALMEIDA ALENCAR MATOS DE ARRUDA

Study of the feasibility of manufacturing and applying an orthopedic implant similar to the locked intramedullary nail produced in polylactic acid (PLA), printed with a 3D printer and inserted into the tibiotarsus of domestic chickens (Gallus gallus domesticus – linnaeus 1758) ex-vivo.

Avian orthopedics, locked intramedullary nail, biodegradable orthopedic implants, 3D printing.

As in other classes of animals, birds present orthopedic lesions that require surgical treatment, among them, fractures are very common conditions. Compared to mammals, there are few scientific studies dedicated specifically to avian orthopedics. Intramedullary locking nails are orthopedic implants applied inside the medullary canal of the bones (neutral axis), therefore, they have great mechanical resistance, being able to efficiently neutralize all the forces acting on the fracture site, in addition to being able to be implanted in a minimally invasive fashion, respecting the precepts of biological osteosynthesis and does not require covering the soft tissues over itself. Therefore, as already demonstrated in the literature, its potential for application in birds is vast and still little explored. Due to complications attributed to the composition of orthopedic implants, around 50 years ago, the first studies of biodegradable polymers as possible substitutes for traditional metallic compounds in the production of orthopedic implants were deloveped. The use  of intramedullary nails made from biodegradable polymers in animals had already been successfully reported. An orthopedic implant, similar to a locked intramedullary nail model, already existing and commercially available on the veterinary market in Brazil, therefore compatible with its implantation system, was developed. Through advanced imaging exams (digital radiology and computed tomography) performed on ex-vivo tibio-tarsal bones of domestic chickens (Gallus gallus domesticus) and measurement of specific measurements using surgical planning software and DICOM image manipulation, the appropriate dimensions of the implant were established. With the aid of online and free CAD (computer aided design) programs, modeling and 3D printing were done successfully. The application of implants developed in polylactic acid polymer (PLA) in the bones of the experiment was made out successfully, with excellent results when carried out using fluoroscopy.