Spinal Cord Injury and Osteoporosis: Causes, Mechanisms, and Rehabilitation Strategies

Spinal cord injury (SCI) has a huge impact on the individual, society and the economy. Though advances in acute care resulted in greatly reduced co-morbidities, there has been much less progress preventing long-term sequelae of SCI. Among the long-term consequences of SCI is bone loss (osteoporosis) due to the mechanical unloading of the paralyzed limbs and vascular dysfunction below the level of injury. Though osteoporosis may be partially prevented via pharmacologic interventions during the acute post-injury phase, there are no clinical guidelines to treat osteoporosis during the chronic phase. Thus there is need for scientific advances to improve the rehabilitative approaches to SCI-related osteoporosis. Recent advances in application of a new technology, functional electrical stimulation, provide a new and exciting opportunity to improve bone metabolism and to provide mechanical strain to the paralyzed lower limbs sufficient to stimulate new bone formation in individuals with SCI. The purpose of this minireview is to delineate our current understanding of SCI-related osteoporosis and to highlight recent literature towards its prevention and treatment.