The aging spine: new technologies and therapeutics for the osteoporotic spine

Abstract

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.

Percutaneous vertebroplasty and kyphoplasty for the stand‐alone augmentation of osteoporosis‐induced vertebral compression fractures: Present status and future directions

“…28 The clinical data on the efficacy of calcitonin are controversial and its mechanism of pain relief is unknown; thus, calcitonin is used mainly as a secondary antiresorptive agent. 29 Since teriparatide is newly approved in the US, very little practice experience has been reported. 27 Narcotic analgesics have a significant negative effect on the patient's quality of life by worsening mood and mentation problems.…”

Betulinic acid synergically enhances BMP2-induced bone formation via stimulating Smad 1/5/8 and p38 pathways

“…Additional complications may include infection, delayed time to healing, morbidity to the donor site as well as the high cost of an operation [ 3 ]. In order to address these drawbacks, several families of drugs designed to up-regulate bone formation and increase bone mass have been developed [ 4 ]. In a few of Asian countries such as Korea, China and Japan, herbal medicines have been widely investigated for their clinical potential to treat bone disease [ 5 , 6 ].…”

Deleterious Effects of Intermittent Recombinant Parathyroid Hormone on Cartilage Formation in a Rabbit Microfracture Model: A Preliminary Study

“…Expression of SOX9 is decreased in cartilage defects that failed to heal, highlighting the importance of this transcription factor in healing of cartilage lesions. Similarly, Lane et al [ 20 ] reported increased expression of Wnt 4, 5a, 5b, and 10b in animals treated with intermittent PTH to stimulate fracture healing. Taken together, these studies suggest that exogenous PTH stimulates fracture healing by increasing the activity of genes such as SOX9 and the Wnt family of proteins to increase chondrogenesis and promote cartilage formation.…”