Bone Loss and the Current Diagnosis of Osteoporosis and Risk of Fragility Fracture in Persons with Spinal Cord Injury

The topics to be discussed in this article include bone loss in the regions of the lower extremity that are most prone to fracture, the risk factors for fracture, the diagnosis of osteoporosis in persons with spinal cord (SCI), the determination of the fracture threshold at the knee, and a brief discussion of future directions. Extensive cross-sectional studies, but a paucity of longitudinal studies, that describe the precipitous bone loss occurs during the acute phase of SCI that likely continues, albeit more gradually, over the lifetime. The distal femur (DF) and proximal tibia (PT) are the regions that are at the highest risk for fracture. The most predictive risk factor for fracture in persons with SCI is low areal bone mineral density (aBMD). Dual energy x-ray absorptiometry (DXA) is the most practical and accurate imaging method to assess DF and PT aBMD but, historically, insufficient standardization of this method has limited its clinical application. The DF and PT regions should be assessed in persons with SCI using recently available DXA acquisition methodology and, once available, applying an appropriate reference dataset at the knee region collected from young, healthy able-bodied individuals.