Animal Models for Spine Biomechanics

Abstract Animal models are commonly used to investigate different aspects of spine biomechanics, such as failure or degeneration processes, implant testing, and spinal deformities. Animal models are generally used because of their lower variability and cost and because they are significantly more available than human specimens are. However, to ensure that the results from such studies are relevant, a good surrogate for the human spine must be selected, and this selection depends on what is being investigated. For example, studies on the mechanical behavior of the spine and implant testing require a model with similar flexibility and mechanical properties of spinal segments, whereas herniation process studies require a good model of the anatomy and mechanical properties of the annulus fibrosus. On the other hand, when degeneration and healing processes are studied, biological parameters such as cell populations are of key importance. This chapter describes the animal models that are most often used in spine biomechanics from anatomical, mechanical, and biological points of view. A comparison of the presented data with the human data is included to aid in the selection of suitable models for any kind of investigation, with the aim of avoiding less relevant research and favoring comparison among studies.