Experimental animal models in scoliosis research: a review of the literature

BACKGROUND CONTEXT: Many animal species and an overwhelming variety of procedures that produce an experimental scoliosis have been reported in the literature. However, varying results have been reported on identical procedures in different animal species. Furthermore, the relevance of experimental animal models for the understanding of human idiopathic scoliosis remains questionable. PURPOSE: To give an overview of the procedures that have been performed in animals in an attempt to induce experimental scoliosis and discuss the characteristics and significance of various animal models. STUDY DESIGN: Extensive review of the literature on experimental animal models in scoliosis research. METHODS: MEDLINE electronic database was searched, focusing on parameters concerning experimental scoliosis in animal models. The search was limited to the English, French, and German languages. RESULTS: The chicken appeared to be the most frequently used experimental animal followed by the rabbit and rat. Additionally, scoliosis has been induced in primates, goats, sheep, pigs, cows, dogs, and frogs. Procedures widely varied from systemic to local procedures. CONCLUSIONS: Although it has been possible to induce scoliosis-like deformities in many animals through various ways, this always required drastic surgical or systemic interventions, thus making the relation to human idiopathic scoliosis unclear. The basic drawback of all used models remains that no animal resembles the upright biomechanical spinal loading condition of man, with its inherent rotational instability of certain spinal segments. The fundamental question remains what the significance of these animal models is to the understanding of human idiopathic scoliosis. (C) 2011 Elsevier Inc. All rights reserved.