Numerical-experimental study of internal fixation system "Dufoo" for vertebral fractures.
BACKGROUND
We describe a numerical experimental study of the stress generated by the internal fixation system "Dufoo" used in the treatment of vertebral fractures with the purpose of validating the numerical model of human lumbar vertebrae under the main physiological loads that the human body is exposed to in this area. The objective is to model and numerically simulate the elements of the musculoskeletal system to collect the stresses generated and other parameters that are difficult to measure experimentally in the thoracic lumbar vertebrae.


METHODS
We used an internal fixator "Dufoo" and vertebrae L2-L3-L4 specimens from pig and human. The system uses a total L3 corpectomy. The fixator acts as a mechanical bridge implant from L2 to L4. Numerical analysis was performed using the finite element method (FEM). For the experimental study, reflective photoelasticity and extensometry were used.


RESULTS
Torsion and combined loads generate the main displacements and stresses in the study system, determining that the internal fixation carries out part of the function of the damaged organ structure when absorbing the stresses presented by applied loads.


CONCLUSIONS
Numerical analysis allows great freedom in the management of the variables involved in the developed models using radiological images. Geometric models are obtained and are entered into FEM programs that allow testing using parameters that, under actual conditions, may not be easily carried out, allowing to comprehensively determine the biomechanical behavior of the coupled system of study.
Unidad Profesional Interdisciplinaria en Ingenierías y Tecnologías Avanzadas, Instituto Politécnico Nacional, Mexico D.F., Mexico. jnietom1@yahoo.com.mx
J Jesús
JJ
Nieto-Miranda
Manuel
M
Faraón-Carbajal Romero
Jons
J
Sánchez-Aguilar
D000818:Animals; D001696:Biomechanical Phenomena; D004867:Equipment Design / Q000706:statistics & numerical data; D005593:Fracture Fixation, Internal / Q000295:instrumentation* / Q000706:statistics & numerical data; D006801:Humans; D066298:In Vitro Techniques; D008159:Lumbar Vertebrae / Q000293:injuries* / Q000601:surgery*; D016103:Spinal Fractures / Q000601:surgery*; D013552:Swine