Treatment of osteoporosis with human parathyroid peptide and observations on effect of sodium fluoride.

OBJECTIVE--To evaluate the need for a randomised study of treatment of spinal osteoporosis with human parathyroid peptide in the secondary prevention of crush fractures; to study the effect of human parathyroid hormone peptide 1-34 plus sex hormones on vertebral body cancellous bone; and, separately, to determine the effect of relatively low doses of sodium fluoride plus calcium on spinal bone mineral density. DESIGN--Open study of patients with primary or postmenopausal osteoporosis. All patients had serial bone densitometry of the spine by quantitative computed tomography and dual photon absorptiometry as well as serial densitometry of the radial midshaft (cortical) and radial distal (trabecular) bone by quantitative computed tomography. Changes in the spinal bone not forming the spongiosa of the vertebral bodies ("cortical" bone) were determined from the difference between the two axial measurements, after correction to the same units of measurement. SETTING--Northwick Park Hospital and Medical Research Council Clinical Research Centre. PATIENTS--24 Patients who fulfilled the conventional criteria for type 1 (vertebral) osteoporosis not secondary to recognised causes other than sex hormone deficiency and with at least one crush or wedge vertebral fracture and a spinal bone density (quantitative computed tomography) less than 80 mg/cm3 or two or more fractures. Twelve patients received human parathyroid peptide and 12 sodium fluoride; they were not randomised. MAIN OUTCOME MEASURES--Trends in axial and peripheral bone mass values determined by linear, time dependent regression analyses. RESULTS--The patients receiving the peptide showed a substantial increase in vertebral spongiosa (mean 25.6 mg/cm2 two years after the start of treatment). No significant changes were seen in spinal cortical or radial bone density. The patients receiving sodium fluoride showed roughly equal increases in cancellous and cortical bone over the same period (mean increase in vertebral spongiosa 16.1 mg/cm3). No significant changes were seen in radial bone. CONCLUSIONS--Treatment of postmenopausal women with human parathyroid peptide selectively increases spinal cancellous bone density by amounts that may prove useful in secondary prevention. Peptide treatment should now be tested in a randomised study in which the important end point is prevention of fractures as the usefulness of sodium fluoride in this context is doubtful.     

Clinical Significance and Pathogenesis of Osteoporosis

The development of osteoporosis with advancing age in man is a widespread if not a universal phenomenon. The average loss between youth and old age amounts to about 15% of the skeleton but involves a much larger proportion of trabecular than of cortical bone.The principal clinical manifestation of osteoporosis is fracture, and three osteoporotic fracture syndromes can be defined: the lower forearm fracture, which predominantly affects women between the ages of 50 and 65; the fracture of the proximal femur, which affects both sexes over the age of 70; and the relatively rare vertebral crush fracture syndrome, which may present at any age but is most common in elderly women.The lower forearm fracture rate is inversely related to the mean normal lower forearm x-ray “density” of the wrist, which falls by about 30% in the 15 years following the menopause. This process, which is associated with corresponding trabecular bone loss elsewhere in the skeleton, is associated with a corresponding rise in the fasting urinary calcium excretion. Some degree of negative calcium balance, and consequent bone resorption, probably occurs in everyone during the later part of the night because calcium absorption is completed within about three to five hours of a meal. In postmenopausal women, however, the sensitivity of the bone to parathyroid hormone appears to be increased, and their nocturnal negative calcium balance therefore comes to exceed the positive balance which can be achieved during the waking hours.Femoral neck fractures in old people reflect the further progression of osteoporosis with advancing age since the fracture rate is inversely correlated with the mean thickness of the metacarpal cortex in the normal population. This progressive osteoporosis is associated with and could well result from a steady decline in calcium absorption which is at least partially attributable to vitamin-D deficiency and reversible on vitamin-D treatment.The vertebral crush fracture syndrome represents a severe degree of spinal osteoporosis which may be associated with relatively normal peripheral bones. It probably results from an accelerated negative calcium balance which mobilizes trabecular bone preferentially. Some of the factors which may contribute to this accelerated negative balance have been identified and include a reduced rate of bone turnover, impaired calcium absorption, and low oestrogen activity as judged by vaginal smears, but there may well be others as yet unidentified.     

Osteoporosis Treatment After Osteoporotic Fractures: Data From a Single Medical Center

ObjectiveMost patients do not receive osteoporosis treatment after osteoporotic fracture. This study reviewed osteoporosis treatment after osteoporotic fractures in a center without a Fracture Liaison Service.MethodsWe identified all patients with hip, vertebral, humeral or radial fractures, evaluated in Meir Medical Center, in 2017. The exclusion criteria were not a Clalit Health Services member, high-energy fracture or 30-day postoperative mortality. The primary endpoint was osteoporosis drugs issued within 12 months of fracture. Secondary endpoints included bone densitometry and 1-year mortality.ResultsFive-hundred-eighty-two patients (average age 78.6 ± 11.1 years, 75.8% women) were included. There were 321 (55.5%) hip, 84 (14.1%) humeral, 33 (5.6%) vertebral, and 144 (24.7%) radial fractures. Osteoporosis drugs were issued to 26.5% of the patients; those with humeral fractures received the least (21.4%) and vertebral, the most (30.3%; P = .51). Bone densitometry was performed in 23.2% of patients. One-year mortality after hip fracture was 12.1%, followed by humeral (3.6%; P < .05). Logistic regression showed that previous treatment (odds ratio [OR] = 7.4; 95% confidence interval [CI] 3.6–15.2), bone densitometry (OR = 4.4; 95% CI 2.6–7.4) and endocrinology visit (OR = 2.6; 95% CI, 1.4–4.6) were the most important factors associated with treatment.ConclusionFewer than one third of patients received pharmacotherapy within 1 year after fracture. Because pharmacotherapy reduces future fractures and mortality, we recommend that medical staff who care for patients with fracture adopt practical and effective strategies to increase treatment rates among patients with osteoporotic fractures.     

单球囊双侧扩张后凸成形术治疗不同程度骨质疏松性椎体压缩骨折的疗效

目的:观察单球囊双侧交替扩张后凸成形术治疗老年骨质疏松性椎体压缩骨折的疗效。方法:选择我院2014年7月-2015年5月收治的老年骨质疏松性椎体压缩骨折患者60例,按照椎体塌陷程度分为重度骨折组和轻度骨折组,每组各30例。两组患者均接受单球囊双侧交替扩张后凸成形术治疗,观察治疗效果和椎体变化等。结果:与轻度骨折组比较,重度骨折组手术时间长、骨水泥注射量少,且椎体前缘高度恢复率、椎体中部高度恢复率、Cobb角矫正度高(P0.05)。治疗后,两组患者VAS评分均优于治疗前(P0.05),但两组间差异无统计学意义(P0.05)。与治疗前比较,两组治疗后椎体前缘高度、椎体中部高度、Cobb角均有所改善(P0.05),轻度骨折组的椎体前缘高度、椎体中部高度明显大于重度骨折组(P0.05),但两组Cobb角比较,差异无统计学意义(P0.05)。结论:单球囊双侧交替扩张后凸成形术治疗老年骨质疏松性椎体压缩骨折具有较好的临床疗效,可以明显纠正椎体塌陷和Cobb角度。     

The prevention and treatment of osteoporosis: a review

Osteoporosis is a disorder characterized by reduced bone strength, diminished bone density, and altered macrogeometry and microscopic architecture. Adult bone mass is the integral measurement of the bone mass level achieved at the peak minus the rate and duration of subsequent bone loss. There is clearly a genetic predisposition to attained peak bone mass, which occurs by a person's mid-20s. Bone loss with age and menopause are universal, but rates vary among individuals. Both peak bone mass and subsequent bone loss can be modified by environmental factors, such as nutrition, physical activity, and concomitant diseases and medications. Osteoporosis prevention requires adequate calcium and vitamin D intake, regular physical activity, and avoiding smoking and excessive alcohol ingestion. Risk of fracture determines whether medication is also warranted. A previous vertebral or hip fracture is the most important predictor of fracture risk. Bone density is the best predictor of fracture risk for those without prior adult fractures. Age, weight, certain medications, and family history also help establish a person's risk for osteoporotic fractures. All women should have a bone density test by the age of 65 or younger (at the time of menopause) if risk factors are present. Guidelines for men are currently in development. Medications include both antiresorptive and anabolic types. Antiresorptive medications--estrogens, selective estrogen receptor modulators (raloxifene), bisphosphonates (alendronate, risedronate, and ibandronate) and calcitonins--work by reducing rates of bone remodeling. Teriparatide (parathyroid hormone) is the only anabolic agent currently approved for osteoporosis in the United States. It stimulates new bone formation, repairing architectural defects and improving bone density. All persons who have had osteoporotic vertebral or hip fractures and those with a bone mineral density diagnostic of osteoporosis should receive treatment. In those with a bone mineral density above the osteoporosis range, treatment may be indicated depending on the number and severity of other risk factors.     

Effect of salcatonin given intranasally on bone mass and fracture rates in established osteoporosis: a dose-response study.

OBJECTIVE--To study the dose related response of salmon calcitonin (salcatonin) given intranasally on bone mass and bone turnover and the effect of salcatonin on rates of fracture in elderly women with moderate osteoporosis. DESIGN--Double blind, placebo controlled, randomised group comparison. SETTING--Outpatient clinic for research into osteoporosis. SUBJECTS--208 healthy women aged 68-72 years who had a bone mineral content of the distal forearm on average 30% below the mean value for healthy premenopausal women. INTERVENTIONS--The 208 women were allocated randomly in blocks of four to two years of treatment with either salcatonin 50 IU, 100 IU, or 200 IU given intranasally or placebo. All groups received a calcium supplement of 500 mg. 32 of the women left the study before its end and 164 women complied with the study criteria throughout. MAIN OUTCOME MEASURES--Bone mineral content of the distal forearm and lumbar spine and rates of vertebral and peripheral fractures after two years of treatment. RESULTS--The average changes in bone mineral content of the spine showed positive outcomes of 1% (95% confidence interval -0.1% to 1.5%) in the group treated with calcium (placebo) and 3% (1.8% to 4.2%) in the group treated with salcatonin 200 IU. There was a significant dose related response to salcatonin, manifested by an increase of 1.0%/100 IU (0.2% to 1.7%, p = 0.008). The rate of patients with new fractures was reduced significantly in the women treated with salcatonin to about one third of that in the non-salcatonin treated women (relative risk 0.23 (0.07 to 0.77)). CONCLUSION--The results suggest that, compared with calcium alone, salcatonin given intranasally reduces the rates of fracture by two thirds in elderly women with moderate osteoporosis. Furthermore, it increases spinal bone mass in a dose dependent manner.     

PKP治疗骨质疏松性椎体压缩骨折的预后评价及继发危险因素分析

目的:分析椎弓根入路行椎体后凸成形术(PKP)治疗骨质疏松性椎体压缩骨折的预后评价及继发危险因素分析。方法:选择2016年2月-2018年2月我院收治的骨质疏松性椎体压缩骨折患者85例纳入本次研究,采用随机数表法分为观察组(n=43)和对照组(n=42)。对照组使用经皮椎体成形术进行治疗,观察组采用PKP进行治疗。比较两组患者手术情况、术后情况、椎体前缘高度丢失率、Cobb角、继发性骨折发生情况及分析骨质疏松性椎体压缩骨折患者术后继发骨折的危险因素。结果:观察组手术时间、透视次数、骨水泥注入量、术中出血量均显著低于对照组,差异显著(P0.05);观察组疼痛缓解时间、下地时间及住院时间均显著低于对照组,差异显著(P0.05);治疗前,两组椎体前缘高度丢失率、Cobb角比较,无显著差异;治疗后,两组患者的椎体高度丢失率明显下降,但两组术后7 d、术后6月两组椎体前缘高度丢失率、Cobb角比较无显著差异;观察组术后12月椎体前缘高度丢失率、Cobb角低于对照组,差异显著(P0.05);所有患者均随访12月,其中22例(25.88%)发生继发性椎体骨折,进行单因素分析,结果发现,两组患者性别、骨折部位、局部矢状面后凸角度、骨水泥量、椎体高度恢复、术后抗骨质疏松治疗差异无统计学意义(P0.05);骨质疏松原因、骨水泥椎间隙渗漏、术后支具佩戴、原发骨折类型与骨质疏松性椎体压缩骨折患者术后发生继发骨折相关(P0.05)。多因素Logistic分析显示,骨质疏松原因、骨水泥椎间隙渗漏、术后支具佩戴、原发骨折类型均是骨质疏松性椎体压缩骨折患者术后发生继发骨折的独立危险因素(P0.05)。结论:在骨质疏松性椎体压缩骨折患者中应用PKP可有效改善手术情况,随着时间的延长,PKP更有利于维持患者椎体高度;骨质疏松原因、骨水泥椎间隙渗漏、术后支具佩戴、原发骨折类型是骨质疏松性椎体压缩骨折患者术后发生继发骨折的危险因素,临床上对于具有危险因素的患者引起重视,并采取干预措施。     

Vertebral morphometry in diagnosis of spinal fractures

Vertebral morphometry was performed on lateral thoracic and lumbar radiographs of 153 women with a preliminary diagnosis of spinal osteoporosis. Measurements included anterior and posterior vertebral height, width, area, wedge angle, percent reduction of anterior to posterior height (PRH) and percent difference in anterior height between adjoining vertebrae (PDAH). A vertebral fracture was identified if any of the measurements which control for interindividual variation in vertebral size (wedge angle, PRH, PDAH) were below the normal range.Among individuals with mild osteoporosis (0–2 fractures) PDAH identified 86% of the fractures and 95% of the individuals with fractures. Other measurements identified less than 71% of the fractures and less than 80% of the individuals with fractures. Although the results reflect a relative rather than a true sensilivity it appears that PDAH is the better diagnostic measurement for fractures in the earlier stages of spinal osteoporosis.     

Organization of the <Emphasis Type="Italic">MASP2</Emphasis> locus and its expression profile in mouse and rat

The identification of vertebral fracture in osteoporosis is based mainly on the identification of abnormal variation in vertebral shape, but this can be misleading in the presence of a non-fracture deformity or normal variant of vertebral shape. Qualitative identification of vertebral fracture (Qual) is influenced by the subjectivity of the approach, and although more objective, the semiquantitative method (SQ) can be difficult to apply. In addition, there has been little independent evaluation of SQ in relation to other approaches. We aimed to evaluate a new algorithm-based approach for the qualitative identification of vertebral fracture (ABQ) and to compare it with SQ and Qual. Two radiologists reported spinal radiographs for 372 postmenopausal women using Qual (reader 1), and SQ and ABQ (reader 2). Non-fracture deformities and normal variants were also reported using Qual and ABQ. The prevalence of vertebral fracture by subjects was higher for SQ (24%) than for Qual (11%) and ABQ (7%). Agreement was poor between SQ and the other methods, and moderate between Qual and ABQ. Twenty-two women with vertebral fracture were agreed by all three methods, similar to the total identified by ABQ (25 women). Seventeen women diagnosed with fracture by Qual, had non-fracture deformity or normal variant (but no fracture) according to ABQ. Of the women with SQ fractures, 53% and 70% were identified negative for fracture but positive for non-fracture deformity or normal variant by ABQ and Qual. The main sources of discrepancy between SQ and the other methods were Scheuermanns disease, normal variation, and degenerative change accompanied by short anterior vertebral height. For all methods, bone mineral density (BMD) and BMD Z-scores were lower in women with vertebral fractures than in those with no fractures. Bone mineral density and BMD Z-scores were also lower at the lumbar spine and total body in women with vertebral fractures according to Qual and ABQ than they were for SQ, and were lower in women with SQ fractures agreed by Qual and ABQ, compared with those diagnosed negative for fracture by Qual and ABQ (p<0.01). We conclude that poor agreement between methods arises mainly from difficulties in differentiating true fracture from non-fracture deformity. Our new approach attempts to address this problem but requires further testing in a larger study population.     

Radiation diagnosis of uncomplicated compression spinal fractures in children

Experiments on rabbits compared the X-ray, morphological, and magnetic resonance imaging of compression fractures of the vertebral body. Edema of the bone marrow of the vertebral body was ascertained to be a basic morphological substrate that evokes a modified MR signal. The data on 178 children with suspected compression fracture of the vertebral body were used to consider the potentialities of MRI and X-ray study in this pathology. The MRI semiotics of uncomplicated compression fractures of vertebral bodies is presented. The sensitivities of MRI and spondylography in the diagnosis of compression fractures of vertebral bodies were 100 and 62.5%, respectively.     

Iatrogenic Osteoporosis,Bilateral Hip Osteonecrosis,and Secondary Adrenal Suppression in an Hiv-Infected Man Receiving Inhaled Corticosteroids and Ritonavir-Boosted Highly Active Antiretroviral Therapy

ObjectiveTo report the first case of severe osteoporosis associated with a vertebral pathologic fracture and osteonecrosis of femoral heads in an HIV-infected man receiving inhaled corticosteroids and ritonavir-boosted antiretroviral therapy.MethodsWe describe an HIV-infected man with severe osteoporosis, bilateral hip osteonecrosis, and secondary adrenal suppression, including detailed clinical, laboratory, and radiographic data, and review the related literature.ResultsA 60-year-old man with a 15-year history of HIV infection and a medical history of long-standing bronchiectasis treated with inhaled corticosteroids and hypogonadism treated with testosterone was referred to the endocrinology clinic after experiencing an osteoporotic vertebral fracture. He was taking ritonavir-boosted antiretroviral therapy. Osteonecrosis of both hips was also diagnosed, which required total hip replacement therapy.Laboratory evaluation revealed adrenal insufficiency due to increased effect of exogenous inhaled steroids and no other secondary causes of osteoporosis. A bone densitometry study showed osteoporosis of both hips and the lumbar spine. He was treated with intravenous pamidronate. During treatment, he developed bilateral femoral fractures after minor trauma.ConclusionsGiven the potential for increased serum levels of inhaled corticosteroids in patients taking ritonavirboosted highly active antiretroviral therapy, attention must be paid to the risk of bone loss in HIV-infected patients taking inhaled corticosteroids. Prescribing calcium and vitamin D supplementation and considering early osteoporosis screening are reasonable measures for this patient population. Interaction between inhaled corticosteroids and ritonavir may increase risk of hypothalamus-pituitary-adrenal axis suppression. (Endocr Pract. 2011;17:74-78)     

经皮椎体成形术治疗骨质疏松性椎体压缩骨折的临床疗效及术后邻近椎体骨折的危险因素分析

摘要 目的：观察骨质疏松性椎体压缩骨折（OVCFs）患者以经皮椎体成形术（PVP）治疗后的临床疗效,并分析术后邻近椎体骨折的危险因素。方法：选取我院2018年6月~2020年9月期间收治的OVCFs患者180例,给予PVP治疗,观察其治疗效果、骨水泥渗漏情况、术后邻近椎体骨折发生情况,采用单因素及多因素Logistic回归分析术后邻近椎体骨折的危险因素。结果：OVCFs患者术前~术后6个月功能障碍指数（ODI）、疼痛视觉模拟评分（VAS）、活动能力评分（LAS）均呈降低趋势（P＜0.05）。随访期间,180例患者中,15例（8.33%）出现了骨水泥渗漏,但均不需要进一步处理。32例（17.78%）出现了术后邻近椎体骨折,148例未出现术后邻近椎体骨折,并以此进行分组。再骨折组、未再骨折组在年龄、骨折病史、骨密度、Cobb角、椎体高度恢复、骨水泥渗漏情况、使用抗骨质疏松药物方面对比有明显差异（P<0.05）。年龄>70岁、骨水泥渗漏、骨密度<-2.5SD、未使用抗骨质疏松药物、Cobb角<15°、椎体高度恢复率>87%均是PVP术后邻近椎体骨折的危险因素（P<0.05）。结论：PVP治疗OVCFs疗效较好,可缓解患者疼痛、减轻功能障碍、改善活动能力,术后邻近椎体骨折的发生受年龄、骨密度、Cobb角等多种因素影响,临床可针对这些因素给予对应的干预措施。     

Micro-CT analysis of cancellous bone fragments from the distal radius fracture zone in osteoporosis]

The incidence and prevalence of osteoporosis must be considered to continue to increase significantly due to the expected demographic development and environmental changes. In the diagnosis and staging of osteoporosis the three-dimensional bone structure should be as important as the bone mass or the mineral content of the bone. In this study, microfragments were taken from distal radius fracture zones and investigated in Micro-CT scans. Patients in which osteodensitometry of the lumbal spine had revealed osteoporosis in were found to have significantly reduced bone mass, bone density and trabecular thickness. Trabecular fractures which were found in non-osteoporotic patients even in robust trabeculae were detected by the two-dimensional analysis in thin locations and arborizations. Despite some trabeculae turned out to be very small the differences in the histomorphometry and the quality of trabecular fractures in osteoporotic as well as non-osteoporotic patients could be visualized very good in the Micro-CT analysis.     

Raloxifene: results from the MORE study

Raloxifene is the first Selective Estrogen Receptor Modulator (SERM) approved for the prevention and treatment of osteoporosis in postmenopausal women. Acting as an estrogen agonist in the skeleton and on lipid metabolism, raloxifene maintains bone mineral density (BMD) and prevents new vertebral fractures while improving the lipid profile in postmenopausal women. In an osteoporosis prevention study, 601 women without osteoporosis, aged 45 to 60 years, were assigned to receive a placebo or raloxifene 30, 60, or 150 mg/day. All women received calcium (400 to 600 mg/day). Raloxifene 60 mg increased BMD by 2.4% at both the lumbar spine and hip compared with the placebo at 36 months. More importantly, however, raloxifene significantly reduced the risk of new vertebral fractures in Multiple Outcomes of Raloxifene Evaluation (MORE), a placebo-controlled, double-blind randomized trial of 7705 postmenopausal women with osteoporosis. The women, with a mean age of 66.5 years, and with hip or spine T-score <-2.5 and/or prevalent vertebral fractures, were assigned to receive either a placebo or 60 mg or 120 mg of raloxifene. All women were provided supplemental calcium (500 mg/day) and vitamin D (400 IU/day). After 36 months, raloxifene 60 mg/day and 120 mg/day, reduced the risk of new vertebral fractures by 55% (RR 0.45, 95% CI 0.3, 0.7; p<0.001), and 40% (RR 0.60, CI 0.4, 0.9) in women without prevalent baseline fractures, respectively; and by 31% (RR 0.7, 95% CI 0.6, 0.9; p<0.001), and 49% (RR 0.5, CI 0.4, 0.6) in women with prevalent baseline fractures compared with the placebo. There was no difference in the proportion of women reporting non-traumatic, non - spine fractures among women receiving raloxifene compared to the placebo-treated women. Compared with placebo, BMD increased after 36 months by 2.1 and 2.6% at the femoral neck and spine, respectively, in the 60mg raloxifene group, and by 2.4 and 2.7% at the femoral neck and spine, respectively, in the 120mg raloxifene group. By 40 months of follow-up, there was a higher rate of deep venous thrombosis (38 cases) and pulmonary embolus (17 cases) in the combined raloxifene groups than in the placebo group (5 and 3 cases,), with a relative risk of 3.1, (CI 1.5-6.2). By 40 months, 54 women had a confirmed diagnosis of breast cancer with a relative risk compared to placebo of 0.35, (CI, 0.21-0.58). Raloxifene therapy for 3 years maintains BMD in healthy postmenopausal women and significantly reduces the risk of new vertebral fractures by about half in postmenopausal women with osteoporosis. Raloxifene also reduces the risk of breast cancer by 65% in postmenopausal women with osteoporosis thus providing a new choice for addressing postmenopausal health concerns.     

Ostéoporose postménopausique : le point sur sa prise en charge

The current management of osteoporosis is based on several keypoints. The first critical step is to identify patients at high risk of fragility fracture, especially those who already sustained a first fracture, but still not often treated. Evaluating fracture risk includes not only bone-mineral density measurement and age, which are the two main risk factors, but also other clinical risk factors. Treatment decision is then based on estimated level of absolute fracture risk over 10 years. In fact, the main goal of postmenopausal osteoporosis treatment is to reduce this risk of fragility fracture. Treatment choice is based both on drug properties demonstrated by clinical trials and the specific fracture risks of each patient. In addition, it is important to identify whether patients are at risk of vertebral fractures or else at risk of vertebral and nonvertebral fractures. Duration of treatment is at least four to five years after which individual-fracture risk has to be reevaluated. As in many other chronic disease treatments, adherence to therapy is poor and has to be carefully assessed by all health-care professionals.     

Treatment of Osteoporosis and Prevention of New Fractures: Role of Intravenously Administered Bisphosphonates

ObjectiveTo evaluate the usefulness of intravenously administered bisphosphonates for improving absorption, tolerability, adherence, and outcomes in the treatment and prevention of osteoporosis.MethodsData published from 1996 to 2009 relevant to the treatment of osteoporosis, with emphasis on bisphosphonates, fracture risk, adherence to therapy, frequency of dosing, intravenous treatment, tolerability, cost-effectiveness, and quality of life, were reviewed.ResultsAlthough bisphosphonates are currently the standard of care for treatment of postmenopausal osteoporosis and osteoporosis in men, oral formulations are associated with poor absorption and potential irritation of the upper gastrointestinal tract. These issues necessitate complicated and restrictive dosing regimens, which in turn lead to poor compliance and persistence. Intravenous formulations such as 3 mg of ibandronate given quarterly and 5 mg of zoledronic acid administered once yearly avoid problems relating to absorption and tolerability by bypassing the gastrointestinal tract. Intravenously administered ibandronate is presumed (by virtue of similar or superior improvements in bone mineral density) to have antifracture efficacy similar to that of orally administered ibandronate given daily, which has been shown to produce significant reductions in vertebral fractures during a 3-year period in comparison with placebo. Zoledronic acid, 5 mg once yearly, has been shown to produce a significant reduction in the risk of morphometric vertebral fractures, clinical vertebral fractures, hip fractures, and nonvertebral fractures versus placebo during a 3-year interval in patients with postmenopausal osteoporosis and also to yield a significantly decreased risk for new clinical fractures versus placebo in patients with recent low-trauma hip fracture. Both agents have favorable safety and tolerability profiles.ConclusionIntravenously administered bisphosphonates have the potential to increase compliance and persistence with therapy in patients with osteoporosis and to improve patient outcomes. (Endocr Pract. 2009;15:483-493)     

Trunk Muscle Activity Is Modified in Osteoporotic Vertebral Fracture and Thoracic Kyphosis with Potential Consequences for Vertebral Health

This study explored inter-relationships between vertebral fracture, thoracic kyphosis and trunk muscle control in elderly people with osteoporosis. Osteoporotic vertebral fractures are associated with increased risk of further vertebral fractures; but underlying mechanisms remain unclear. Several factors may explain this association, including changes in postural alignment (thoracic kyphosis) and altered trunk muscle contraction patterns. Both factors may increase risk of further fracture because of increased vertebral loading and impaired balance, which may increase falls risk. This study compared postural adjustments in 24 individuals with osteoporosis with and without vertebral fracture and with varying degrees of thoracic kyphosis. Trunk muscle electromyographic activity (EMG) associated with voluntary arm movements was recorded and compared between individuals with and without vertebral fracture, and between those with low and high thoracic kyphosis. Overall, elderly participants in the study demonstrated co-contraction of the trunk flexor and extensor muscles during forwards arm movements, but those with vertebral fractures demonstrated a more pronounced co-contraction than those without fracture. Individuals with high thoracic kyphosis demonstrated more pronounced alternating flexor and extensor EMG bursts than those with less kyphosis. Co-contraction of trunk flexor and extensor muscles in older individuals contrasts the alternating bursts of antagonist muscle activity in previous studies of young individuals. This may have several consequences, including altered balance efficacy and the potential for increased compressive loads through the spine. Both of these outcomes may have consequences in a population with fragile vertebrae who are susceptible to fracture.     

Effect of vertebral body stiffness before and after vertebroplasty on intradiscal pressure]

Fractures of osteoporotic vertebral bodies are increasingly stabilized with bone cement. The effects of vertebral-body stiffness before and after augmentation with bone cement and of wedge-shaped vertebral body fractures on intradiscal pressure are insufficiently known. In a finite element model of the lumbar spine the elastic modulus of cancellous bone as well as the amount and the elastic modulus of bone cement were varied and the dependency of intradiscal pressure on these parameters was calculated. In addition, a wedge-shaped vertebral-body fracture was simulated. The bulge of the vertebral-body endplate and thus the intradiscal pressure depends strongly on the grade of osteoporosis in the vertebral body. The influence of amount and elastic modulus of bone cement on intradiscal pressure is small. A wedge-shaped vertebral-body fracture causes an anterior shift of upper-body centre of gravity. If this shift is not compensated, it leads to an increased flexion moment that has to be balanced by muscle forces. In addition, this shift leads to a stronger increase of intradiscal pressure than the augmentation of the vertebral body with bone cement.     

Human evolution and osteoporosis-related spinal fractures

The field of evolutionary medicine examines the possibility that some diseases are the result of trade-offs made in human evolution. Spinal fractures are the most common osteoporosis-related fracture in humans, but are not observed in apes, even in cases of severe osteopenia. In humans, the development of osteoporosis is influenced by peak bone mass and strength in early adulthood as well as age-related bone loss. Here, we examine the structural differences in the vertebral bodies (the portion of the vertebra most commonly involved in osteoporosis-related fractures) between humans and apes before age-related bone loss occurs. Vertebrae from young adult humans and chimpanzees, gorillas, orangutans, and gibbons (T8 vertebrae, n = 8–14 per species, male and female, humans: 20–40 years of age) were examined to determine bone strength (using finite element models), bone morphology (external shape), and trabecular microarchitecture (micro-computed tomography). The vertebrae of young adult humans are not as strong as those from apes after accounting for body mass (p<0.01). Human vertebrae are larger in size (volume, cross-sectional area, height) than in apes with a similar body mass. Young adult human vertebrae have significantly lower trabecular bone volume fraction (0.26±0.04 in humans and 0.37±0.07 in apes, mean ± SD, p<0.01) and thinner vertebral shells than apes (after accounting for body mass, p<0.01). Since human vertebrae are more porous and weaker than those in apes in young adulthood (after accounting for bone mass), even modest amounts of age-related bone loss may lead to vertebral fracture in humans, while in apes, larger amounts of bone loss would be required before a vertebral fracture becomes likely. We present arguments that differences in vertebral bone size and shape associated with reduced bone strength in humans is linked to evolutionary adaptations associated with bipedalism.     

MTHFR C677T polymorphism and osteoporotic fractures.

The C677T (rs1801133) polymorphism of MTHFR (methylenetetrahydrofolate reductase) has been associated with the risk of cardiovascular events, and also with osteoporosis in some studies. However, the results are controversial. Our objective was to determine the relationship of the polymorphism with osteoporotic fractures by means of a case-control study. C677T was analyzed in 823 subjects (365 controls, 136 with vertebral fractures and 322 with hip fracture) by using a Taqman assay. The distribution of MTHFR genotypes was similar in patients and controls. In comparison with TC/CC genotypes, the age-adjusted OR for hip fractures of the TT genotype was 1.0 (95% confidence interval 0.6-1.7) in women and 0.7 (0.3-1.8) in men. The OR for vertebral fractures was 0.8 (0.4-1.7) in women and 1.7 (0.4-6.7) in men. A meta-analysis combining these data with previous reports confirmed the lack of association between MTHFR and fractures, with an OR of 1.1 (0.7-1.9, p=0.65) for vertebral fractures and 1.2 (0.7-2.0; p=0.45) for peripheral fractures, but there was significant heterogeneity among the results of individual studies, particularly about peripheral fractures. In conclusion, the C677T polymorphism of the MTHFR gene does not appear to be associated with the overall risk of osteoporotic fractures. However, given the heterogeneity of the results of published studies, further investigations are needed to evaluate its influence in specific population subgroups.