title: Development and kinematic verification of a finite element model for the lumbar spine: application to disc degeneration.
abstract: The knowledge of the lumbar spine biomechanics is essential for clinical applications. Due to the difficulties to experiment on living people and the irregular results published, simulation based on finite elements (FE) has been developed, making it possible to adequately reproduce the biomechanics of the lumbar spine. A 3D FE model of the complete lumbar spine (vertebrae, discs, and ligaments) has been developed. To verify the model, radiological images (X-rays) were taken over a group of 25 healthy, male individuals with average age of 27.4 and average weight of 78.6 kg with the corresponding informed consent. A maximum angle of 34.40° is achieved in flexion and of 35.58° in extension with a flexion-extension angle of 69.98°. The radiological measurements were 33.94 ± 4.91°, 38.73 ± 4.29°, and 72.67°, respectively. In lateral bending, the maximum angles were 19.33° and 23.40 ± 2.39, respectively. In rotation a maximum angle of 9.96° was obtained. The model incorporates a precise geometrical characterization of several elements (vertebrae, discs, and ligaments), respecting anatomical features and being capable of reproducing a wide range of physiological movements. Application to disc degeneration (L5-S1) allows predicting the affection in the mobility of the different lumbar segments, by means of parametric studies for different ranges of degeneration.
authors.affiliation: Department of Mechanical Engineering, University of Zaragoza, 50018 Zaragoza, Spain.
authors.forename: Elena
authors.initials: E
authors.lastname: Ibarz
authors.forename: Antonio
authors.initials: A
authors.lastname: Herrera
authors.forename: Yolanda
authors.initials: Y
authors.lastname: Más
authors.forename: Javier
authors.initials: J
authors.lastname: Rodríguez-Vela
authors.forename: José
authors.initials: J
authors.lastname: Cegoñino
authors.forename: Sergio
authors.initials: S
authors.lastname: Puértolas
authors.forename: Luis
authors.initials: L
authors.lastname: Gracia
mesh_terms: D000328:Adult; D001696:Biomechanical Phenomena; D003198:Computer Simulation; D004548:Elasticity; D020342:Finite Element Analysis; D006801:Humans; D007403:Intervertebral Disc / Q000000981:diagnostic imaging / Q000503:physiopathology; D055959:Intervertebral Disc Degeneration / Q000000981:diagnostic imaging* / Q000503:physiopathology; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging* / Q000502:physiology*; D008297:Male; D008953:Models, Anatomic; D011312:Pressure; D011859:Radiography; D016059:Range of Motion, Articular / Q000502:physiology; D016474:Weight-Bearing / Q000502:physiology; D014965:X-Rays