A Review of the Occurrence and Mechanisms of Induction of Osteoporosis Following Spinal Cord Injury

Introduction: Spinal cord injury (SCI) causes devastating injuries in patients. The main mechanisms of the pathogenesis of secondary injury include nerve degeneration, gliosis, and inflammation. Spinal cord injury induces a disorder or failure in several organs due to the vital role of the spinal cord in regulating bodily functions. Osteoporosis is a consequence of spinal cord injury that occurs in the vast majority of patients with spinal cord injury. Articles on the related topic were searched in the following databases: Science Direct, Scopus, Springer Science, PubMed and Google scholar to have been used in writing from this review article. A total of 120 related research papers, including quantitatve and qualitative researches in English, from the last 57 years papers (1962- 2019) were included in this study. The review article is written according to 120 articles and the keywords “Spinal cord injury, Osteoporosis, Inflammation, Osteoblast and Osteoclast”. Conclusion: Although weight loss is an important factor in the development of osteoporosis following SCI, inflammation, nerve damage, and hormonal changes also contribute to this process. Hormonal changes mediated by SCI may contribute to postoperative osteoporosis with several mechanisms. These mechanisms included: increased renal excretion and decreased intestinal absorption of calcium, consequently, a negative balance of calcium ions; Vitamin D deficiency; impair the function of the gonads and inhibits the osteoanabolic (ossification) activity of sex steroids; elevated blood leptin; Pituitary suppression of parathyroid hormone, and bone loss following SCI may (at least in part) be caused directly by insulin resistance and insulin-like growth factor.