IntroductionOsteoporosis is a serious problem in the United States, affecting as many as 13-18% of women and 3-6% of men [49, 55,64,68,89]. If untreated, it is estimated that more than half of all Caucasian white women will sustain an osteoporotic fracture during their lifetime [16,89]. Approximately one-half of these fractures are related to the vertebral bodies, with two-thirds being silent and one-third symptomatic. Epidemiological studies have demonstrated that multiple vertebral fractures increase morbidity [67,69], and the presence and increasing numbers of fractures significantly increase mortality rates [11, 23, 41, 48]. Despite the recognition that osteoporotic fractures increase the risk for additional vertebral fractures as well as hip fractures, the majority of individuals with these fractures remain undiagnosed and untreated [28, 31,74].Over the last ten years, great strides have been made in understanding the pathophysiology of osteoporotic vertebral fractures. Radiographic methods have been enhanced to aid in the diagnosis of osteoporosis. New therapeutics have been developed that may decrease the fragility fracture rate by up to 50% compared with controls treated only with calcium [7, 24, 40,70,79]. During the same time period, two minimally invasive procedures have been developed to rapidly address painful vertebral fractures -vertebroplasty and kyphoplasty. Details regarding these procedures are the subject of separate articles within this issue.
Fracture etiology: factor of riskVertebral bodies sustain fractures under two different mechanical environments: repetitive loading that fatigues the cancellous bone and leads to the accumulation of microfractures, or single traumatic events may overload the vertebral body and lead to fracture [58]. To understand the etiology of vertebral fracture, information about the loads imposed onto the vertebral body and the load-bearing capacity of the vertebrae at the time of risk need to be quantified. This concept has been defined as the factor of risk, and represents the ratio of the load applied to the bone over the load necessary to cause a fracture [42]. The load Abstract Osteoporosis results in low-energy fractures of the spine. The load necessary to cause a vertebral fracture is determined by the characteristics related to the vertebral body structure, mineral content, and quality of bone. Radiographic techniques centered on dual X-ray absorptiometry (DXA) permit a determination of bone mass and fracture risk. Current medical therapies principally using bisphosphonate and pulsatile PTH profoundly decrease the risk of fracture (50+%). Fall prevention strategies can further decrease the possibility of fracture. A comprehensive approach to osteoporosis can favorably alter the disease.