Finite element comparison between the human and the ovine lumbar intervertebral disc

Abstract

Introduction: Nowadays it is still not clear which loading conditions are responsible for lumbar intervertebral disc failure. Many studies have been conducted to investigate the effect of different loading conditions on the herniation processes, and many of them were based on the ovine model. However, the biomechanical similarities between the human and the ovine lumbar disc have been demonstrated in the main planes only, whereas it is not known if they are comparable under complex loading conditions too. The aim of this study was to compare the mechanical response of the ovine and the human lumbar intervetebral disc under complex loading conditions, in order to investigate differences and similarities between the species. The loading scenarios described in a finite element study on a human lumbar segment were applied to a model of the ovine disc, and the results were then compared. It has been shown that combined loads generated highest strains in both the models, and the maximum strains had the same location in the posterior or in the postero-lateral region of the annulus, according to the loading scenario. Conclusion: The ovine disc can be used in spinal research to investigate herniation process under any loading conditions. Level of evidence: V.KEY WORDS: animal model, finite element analysis, anisotropic hyperelastic.

Comparison of biomechanical parameters of two Chinese cervical spine rotation manipulations based on motion capture and finite element analysis

“…Meanwhile, we compared the obtained stresses and strains in each segment of the disc with the literature. Casaroli et al (2017a) reported that in the human disc, the stresses in the disc were up to 0.44 MPa in lateral bending, 0.57 MPa in axial rotation, 0.62 MPa in posterior extension and 0.71 MPa in anterior Casaroli et al (2017b) concluded that an axial stress of 12 MPa would result in disc failure, i.e., yield stress of the disc, while an axial stress of 4 MPa would not produce any damage. Our finite element model obtained disc stress intervals between 0.023-0.064 MPa and 0.069–0.267 MPa for the spin-lift and tilt-plate maneuvers, respectively, which do not reach the threshold of disc damage, and although the stress on the disc for the tilt-plate maneuver is greater than that for the spin-lift maneuver, neither exceeds the threshold of damage and both are safer cervical rotation Both are safe cervical rotation techniques.…”

Skeletal Muscle Fibre Characteristics of the Lumbar Multifidus Muscle in Patients Undergoing Microdiscectomy for Unilateral Lumbar Disc Herniation

“…Nowadays it is not clear which loading conditions are responsible for lumbar intervertebral disc failure. Due to similar mechanical behaviour of the ovine and human intervertebral disc, the ovine model can be used to investigate the mechanical loading on the intervertebral disc itself (4). In a selected group of patients experiencing progressive neurological deficits, red flags, or failure of conservative management, surgery may be required (5).…”