Transdermal fentanyl for the treatment of back pain caused by vertebral osteoporosis

Pain relief for patients with osteoporosis is important to maintain mobility and facilitate physical therapy. Transdermal fentanyl may be useful but has not been studied systematically. Patients with at least one osteoporotic vertebral fracture requiring strong opioids were enrolled and received transdermal fentanyl. Treatment history, pain, ease of physical therapy, and quality of life were recorded at baseline and after 4 weeks. Of 64 patients enrolled, 49 completed the study; 12 withdrew because of adverse events, most commonly nausea, vomiting, or dizziness. Pain at rest and on movement decreased significantly from baseline to final assessment (mean scores 7.84 and 8.55, respectively, at baseline, falling to 3.56 and 4.50 after 4 weeks). Quality of life improved significantly, and 61% of patients were satisfied with the treatment. Ability to undergo physical therapy improved significantly. Transdermal fentanyl is useful for the treatment of severe back pain caused by osteoporosis.

Is the predictive power of previous fractures for new spine and non-spine fractures associated with biochemical evidence of altered bone remodelling? The EPOS study. European Prospective Osteoporosis Study

BACKGROUND

In the European Prospective Osteoporosis Study (EPOS), a past spine fracture increased risk of an incident fracture 3.6 - 12-fold even after adjusting for BMD. We examined the possibility that biochemical marker levels were associated with this unexplained BMD-independent element of fracture risk.

METHODS

Each of 182 cases in EPOS of spine or non-spine fracture that occurred in 3.8 years of follow-up was matched by age, sex and study centre with two randomly assigned never-fractured controls and one case of past fracture. Analytes measured blind were: osteocalcin, bone-specific alkaline phosphatase, total alkaline phosphatase, serum creatinine, calcium, phosphate and albumin, together with the collagen cross-links degradation products serum CTS and urine CTX. Most subjects also had bone density measured by DXA.

RESULTS

Cases who had recent fractures did not differ in marker levels from cases who had their last fracture more than 3 years previously. No statistically significant effect of recent fracture was found for any marker except osteocalcin, which was 17.6% lower in recent peripheral cases compared to unfractured controls (p<0.05) and this was independent of BMD.

CONCLUSION

Past fracture as a risk indicator for future fracture is not strongly mediated through increased bone turnover.

Oxygen uptake in whole-body vibration exercise: influence of vibration frequency, amplitude, and external load

Vibration exercise (VbX) is a new type of physical training to increase muscle power. The present study was designed to assess the influence of whole-body VbX on metabolic power. Specific oxygen uptake (sVO(2)) was assessed, testing the hypotheses that sVO(2) increases with the frequency of vibration (tested in 10 males) and with the amplitude (tested in 8 males), and that the VbX-related increase in sVO(2) is enhanced by increased muscle force (tested in 8 males). With a vibration amplitude of 5 mm, a linear increase in sVO(2) was found from frequencies 18 to 34 Hz (p < 0.01). Each vibration cycle evoked an oxygen consumption of approximately 2.5 micro l x kg(-1). At a vibration frequency of 26 Hz, sVO(2) increased more than proportionally with amplitudes from 2.5 to 7.5 mm. With an additional load of 40 % of the lean body mass attached to the waist, sVO(2) likewise increased significantly. A further increase was observed when the load was applied to the shoulders. The present findings indicate that metabolic power in whole-body VbX can be parametrically controlled by frequency and amplitude, and by application of additional loads. These results further substantiate the view that VbX enhances muscular metabolic power, and thus muscle activity.

Discordance between the degree of osteopenia and the prevalence of spontaneous vertebral fractures in Crohn's disease

BACKGROUND

A high prevalence of osteoporosis has been noted in Crohn's disease, but data about fractures are scarce.

METHODS

The relationship between low bone mineral density and the prevalence of vertebral fractures was studied in 271 patients with ileo-caecal Crohn's disease in a large European/Israeli study. One hundred and eighty-one currently steroid-free patients with active Crohn's disease (98 completely steroid-naive) and 90 steroid-dependent patients with inactive or quiescent Crohn's disease were investigated by dual X-ray absorptiometry scan of the lumbar spine, a standardized posterior/anterior and lateral X-ray of the thoracic and lumbar spine, and an assessment of potential risk factors for osteoporosis.

RESULTS

Thirty-nine asymptomatic fractures were seen in 25 of 179 steroid-free patients (14.0%; 27 wedge, 12 concavity), and 17 fractures were seen in 13 of 89 steroid-dependent patients (14.6%; 14 wedge, three concavity). The prevalence of fractures in steroid-naive patients was 12.4%. The average bone mineral density, expressed as the T-score, of patients with fractures was not significantly different from that of those without fractures (-0.759 vs. -0.837; P=0.73); 55% of patients with fractures had a normal T-score. The bone mineral density was negatively correlated with lifetime steroids, but not with previous bowel resection or current disease activity. The fracture rate was not correlated with the bone mineral density (P=0.73) or lifetime steroid dose (P=0.83); in women, but not in men, the fracture rate was correlated with age (P=0.009).

CONCLUSIONS

The lack of correlation between the prevalence of fractures on the one hand and the bone mineral density and lifetime steroid dose on the other necessitates new hypotheses for the pathogenesis of the former.

Incidence of limb fracture across Europe: results from the European Prospective Osteoporosis Study (EPOS)

The aim of this population-based prospective study was to determine the incidence of limb fracture by site and gender in different regions of Europe. Men and women aged 50-79 years were recruited from population registers in 31 European centers. Subjects were invited to attend for an interviewer-administered questionnaire and lateral spinal radiographs. Subjects were subsequently followed up using an annual postal questionnaire which included questions concerning the occurrence of new fractures. Self-reported fractures were confirmed where possible by radiograph, attending physician or subject interview. There were 6451 men and 6936 women followed for a median of 3.0 years. During this time there were 140 incident limb fractures in men and 391 in women. The age-adjusted incidence of any limb fracture was 7.3/1000 person-years [pyrs] in men and 19 per 1000 pyrs in women, equivalent to a 2.5 times excess in women. Among women, the incidence of hip, humerus and distal forearm fracture, though not 'other' limb fracture, increased with age, while in men only the incidence of hip and humerus fracture increased with age. Among women, there was evidence of significant variation in the occurrence of hip, distal forearm and humerus fractures across Europe, with incidence rates higher in Scandinavia than in other European regions, though for distal forearm fracture the incidence in east Europe was similar to that observed in Scandinavia. Among men, there was no evidence of significant geographic variation in the occurrence of these fractures. This is the first large population-based study to characterize the incidence of limb fracture in men and women over 50 years of age across Europe. There are substantial differences in the descriptive epidemiology of limb fracture by region and gender.

Incidence of vertebral fracture in europe: results from the European Prospective Osteoporosis Study (EPOS)

Vertebral fracture is one of the major adverse clinical consequences of osteoporosis; however, there are few data concerning the incidence of vertebral fracture in population samples of men and women. The aim of this study was to determine the incidence of vertebral fracture in European men and women. A total of 14,011 men and women aged 50 years and over were recruited from population-based registers in 29 European centers and had an interviewer-administered questionnaire and lateral spinal radiographs performed. The response rate for participation in the study was approximately 50%. Repeat spinal radiographs were performed a mean of 3.8 years following the baseline film. All films were evaluated morphometrically. The definition of a morphometric fracture was a vertebra in which there was evidence of a 20% (+4 mm) or more reduction in anterior, middle, or posterior vertebral height between films--plus the additional requirement that a vertebra satisfy criteria for a prevalent deformity (using the McCloskey-Kanis method) in the follow-up film. There were 3174 men, mean age 63.1 years, and 3,614 women, mean age 62.2 years, with paired duplicate spinal radiographs (48% of those originally recruited to the baseline survey). The age standardized incidence of morphometric fracture was 10.7/1,000 person years (pyr) in women and 5.7/1,000 pyr in men. The age-standardized incidence of vertebral fracture as assessed qualitatively by the radiologist was broadly similar-12.1/1,000 pyr and 6.8/1,000 pyr, respectively. The incidence increased markedly with age in both men and women. There was some evidence of geographic variation in fracture occurrence; rates were higher in Sweden than elsewhere in Europe. This is the first large population-based study to ascertain the incidence of vertebral fracture in men and women over 50 years of age across Europe. The data confirm the frequent occurrence of the disorder in men as well as in women and the rise in incidence with age.

Oxygen uptake during whole-body vibration exercise: comparison with squatting as a slow voluntary movement

In this study we investigated metabolic power during whole-body vibration exercise (VbX) compared to mild resistance exercise. Specific oxygen consumption (VO2) and subjectively perceived exertion (rating of perceived exertion, RPE; Borg scale) were assessed in 12 young healthy subjects (8 female and 4 male). The outcome parameters were assessed during the last minute of a 3-min exercise bout, which consisted of either (1) simple standing, (2) squatting in cycles of 6 s to 90 degrees knee flexion, and (3) squatting as before with an additional load of 40% of the subject's body weight (35% in females). Exercise types 1-3 were performed with (VbX+) and without (VbX-) platform vibration at a frequency of 26 Hz and an amplitude of 6 mm. Compared to the VbX- condition, the specific VO2 was increased with vibration by 4.5 ml x min(-1) x kg(-1). Likewise, squatting and the additional load were factors that further increased VO2. Corresponding changes were observed in RPE. There was a correlation between VbX- and VbX+ values for exercise types 1-3 (r = 0.90). The correlation coefficient between squat/no-squat values (r = 0.70 without and r = 0.71 with the additional load) was significantly lower than that for VbX-/VbX+. Variation in specific VO2 was significantly higher in the squatting paradigm than with vibration. It is concluded that the increased metabolic power observed in association with VbX is due to muscular activity. It is likely that this muscular activity is easier to control between individuals than is simple squatting.

Bone architecture assessment with measures of complexity

Architectural changes in trabecular bone by osteoporosis were utilized as a model for the changes which probably occur in human bone while exposed to microgravity conditions. Although there are many concerns about microgravity-induced bone loss, little is known about the impact of microgravity on the three-dimensional architecture of the skeleton. 50 (level L3) and 57 (level L4) vertebral bones harvested from human cadavers were investigated by computed tomography (CT) and quantified in terms of bone mineral density (BMD). Based on the symbol-encoded transformed CT-images, five measures of complexity were developed which quantify the structural composition of the trabecular bone. This quantification determines the bone architecture as a whole. Depending on the specific measure of complexity and its relation to BMD, a 5-10% change of BMD is related to a 5-90% change in structural composition. The method requires a non-invasive CT-procedure of the lumbar spine resulting in a radiation exposure of about 30 microSv effective dose. The technique is useful for the evaluation of the bone status of space-flying, personnel as well as for patients on ground. Grant numbers: BMH1-CT92-0296.

Osteoporosis changes the amount of vertebral trabecular bone at risk of fracture but not the vertebral load distribution

STUDY DESIGN

A finite-element study to investigate the amount of trabecular bone at risk of fracture and the distribution of load between trabecular core and cortical shell, for healthy, osteopenic, and osteoporotic vertebrae.

OBJECTIVES

To determine differences between healthy, osteopenic, and osteoporotic vertebrae with regard to the risk of fracture and the load distribution.

SUMMARY OF BACKGROUND DATA

The literature contains no reports on the effects of osteopenia and osteoporosis on load distribution in vertebral bodies, nor any reports on the amount of trabecular bone at risk of fracture.

METHODS

Computed tomography data of vertebral bodies were used to construct patient-specific finite-element models. These models were then used in finite-element analyses to determine the physiologic stresses and strains in the vertebrae.

RESULTS

For all three classes of vertebrae the contribution of the trabecular core to the total load transfer decreased from about 70% near the endplates to about 50% in the midtransverse region. The amount of trabecular bone that is at risk of fracture was about 1% for healthy vertebrae, about 3% for osteopenic vertebrae, and about 16% for osteoporotic vertebrae.

CONCLUSIONS

Our finite-element models indicated that neither osteopenia nor osteoporosis had any effect on the contribution of the trabecular core to the total load placed on the vertebra. The trabecular core carried about half the load. Our finite-element models indicated that osteoporosis had a significant effect on the amount of trabecular bone at risk of fracture, which increased from about 1% in healthy vertebrae to about 16% for osteoporotic vertebrae.

Brain atrophy parameters of very old subjects in a population - based sample with and without dementia syndrome

Atrophy parameters of the brain vary with age in healthy subjects. The aim of the study was to determine the range of atrophy parameters in subjects with very old age. Population-based data are especially necessary in order to evaluate atrophy parameters of healthy old persons in clinical settings and for the diagnosis of dementia diseases. 254 subjects in a population-based sample were investigated by a cranial computerized tomography (cCT). Age ranged from 70 to 99, 78 were 80-89 years old and 43 over 90 years of age; 24 demented subjects were diagnosed according to DSM-III-R. A planimetric analysis of the extracerebral CSF-space (ECSF) and relative area of the ventricles (VBR) was performed. VBR and ECSF were used as primary atrophy parameters. The VBR, ECSF and other structural brain parameters for subjects of very old age are described after exclusion of dementia cases according to clinical diagnosis. A statistically significant age effect could be demonstrated as well as a dementia effect for the younger age groups (70-89). No difference in the atrophy parameters between the diagnostic groups, however, were found for the oldest groups (90 and older); for the very old subjects the scores of demented and non-demented participants were entirely within the same range. The age effect on atrophy parameters in non-demented subjects in very old age reaches the range of atrophy parameters, which is found in dementia. The question remains wheather the reason for this is a benign senescent brain atrophy or whether the amount of atrophic changes in very old age may explain the enhanced vulnerability for the development of dementia syndromes in very old age and the steeply increasing incidence of dementia or whether there is an incipient brain atrophy in more or less all very old subject and they will develop dementia if they do not die before-hand.

Prediction of osteoporotic fractures by bone densitometry and COLIA1 genotyping: a prospective, population-based study in men and women

Osteoporosis is a common disease with a strong genetic component, characterized by reduced bone mineral density and increased fracture risk. Although the genetic basis of osteoporosis is incompletely understood, previous studies have identified a polymorphism affecting an Sp1 binding site in the COLIA1 gene that predicts bone mineral density and osteoporotic fractures in several populations. Here we investigated the role of COLIA1 genotyping and bone densitometry in the prediction of osteoporotic fractures in a prospective, population-based study of men (n = 156) and women (n = 185) who were followed up for a mean (+/- SEM) of 4.88+/-0.03 years. There was no significant difference in bone density, rate of bone loss, body weight, height, or years since menopause between the genotype groups but women with the 'ss' genotype were significantly older than the other genotype groups (p = 0.03). Thirty-nine individuals sustained 54 fractures during follow-up and these predominantly occurred in women (45 fractures in 30 individuals). Fractures were significantly more common in females who carried the COLIA1 's' allele (p = 0.001), although there was no significant association between COLIA1 genotype and the occurrence of fractures in men. Logistic regression analysis showed that carriage of the COLIA1 's' allele was an independent predictor of fracture in women with an odds ratio (OR) [95% CI] of 2.59 [1.23-5.45], along with spine bone mineral density (OR = 1.57 [1.04-2.37] per Z-score unit) and body weight (OR = 1.05 [1.01-1.10] per kilogram). Moreover, bone densitometry and COLIA1 genotyping interacted significantly to enhance fracture prediction in women (p = 0.01), such that the incidence of fractures was 45 times higher in those with low BMD who carried the 's' allele (24.3 fractures/100 patient-years) compared with those with high BMD who were 'SS' homozygotes (0.54 fracture/100 patient-years). We conclude that in our population, COLIA1 genotyping predicts fractures independently of bone mass and interacts with bone densitometry to help identify women who are at high and low risk of sustaining osteoporotic fractures.

Prevalent vertebral deformity predicts incident hip though not distal forearm fracture: results from the European Prospective Osteoporosis Study

The presence of a vertebral deformity increases the risk of subsequent spinal deformities. The aim of this analysis was to determine whether the presence of vertebral deformity predicts incident hip and other limb fractures. Six thousand three hundred and forty-four men and 6788 women aged 50 years and over were recruited from population registers in 31 European centers and followed prospectively for a median of 3 years. All subjects had radiographs performed at baseline and the presence of vertebral deformity was assessed using established morphometric methods. Incident limb fractures which occurred during the follow- up period were ascertained by annual postal questionnaire and confirmed by radiographs, review of medical records and personal interview. During a total of 40348 person-years of follow-up, 138 men and 391 women sustained a limb fracture. Amongst the women, after adjustment for age, prevalent vertebral deformity was a strong predictor of incident hip fracture, (rate ratio (RR) = 4.5; 95% CI 2.1-9.4) and a weak predictor of 'other' limb fractures (RR = 1.6; 95% CI 1.1-2.4), though not distal forearm fracture (RR = 1.0; 95% CI 0.6-1.6). The predictive risk increased with increasing number of prevalent deformities, particularly for subsequent hip fracture: for two or more deformities, RR = 7.2 (95% CI 3.0-17.3). Amongst men, vertebral deformity was not associated with an increased risk of incident limb fracture though there was a nonsignificant trend toward an increased risk of hip fracture with increasing number of deformities. In summary, prevalent radiographic vertebral deformities in women are a strong predictor of hip fracture, and to a lesser extent humerus and 'other' limb fractures; however, they do not predict distal forearm fractures.

The effects of lifestyle, dietary dairy intake and diabetes on bone density and vertebral deformity prevalence: the EVOS study

The risk of low and moderate energy fracture is related to bone mineral density (BMD). Yet it is uncertain whether the epidemiologic determinants of fracture risk are the same as for low bone density. The European Vertebral Osteoporosis Study was a population-based prevalence study of vertebral deformity in 36 age-stratified population samples aged 50-80 years. In nearly 4000 subjects (13 centers), BMD measurements were also made at the spine, femoral neck and femoral trochanter. To investigate whether effects of reported physical activity on spine deformity risk were mediated through BMD, we modeled these and other risk factor data with BMD as the dependent variate after adjusting for age, center, sex and body mass index (BMI). The significant determinants of vertebral deformity risk were also entered into logistic models of deformity risk that included BMD measurements as covariates. Both current and lifetime physical activity were positively associated with BMD. This effect was stronger with hip BMD than with spine BMD. Lifetime smoking exposure was associated with reduced BMD. Type 2 diabetes mellitus was associated with increased BMD. Weak positive associations were found between consumption of dairy products and BMD at the three measured sites and these were strengthened by an interaction with measures of physical activity in men. Physical activity in women had the largest beneficial effect in lean women and in women exposed to hormone replacement therapy. When fracture risk was modeled with BMD as a covariate, the lifestyle and dietary determinants became less strongly related to vertebral deformity risk, suggesting that BMD may have acted as an intermediary variable. However, heavy physical activity in men still increased spine deformity risk after adjusting for BMD. It is concluded that physical activity in both genders and milk consumption in young women might protect against vertebral deformities in later life through their effects on bone density. The adverse effect of smoking on BMD was confirmed. Heavy physical activity in men might increase spine deformity risk even when BMD is normal.

A statistical method to minimize magnification errors in serial vertebral radiographs

Incident vertebral deformities are commonly defined by observed changes in height between measurements on two consecutive radiographs. However, conventional radiographs are subject to magnification, and this magnification may differ between films, leading to artifactual changes in height. In order to minimize this effect, it is common practice to record the spine-film and film-focus distances, and from this to calculate a magnification factor for each film. We present a simple statistical method for correcting for differences in magnification between two films if the spine-film and film-focus distances are unknown. This method is shown to reduce the variance of the magnification differences in vertebral heights by 14%, considerably more than is possible using the spine-film distance. Using the statistical method, the number of vertebrae that showed not only a reduction in one or more height of 15%, but were also judged clinically to be free from any incident deformity by an expert radiologist, was reduced from 100 to 46. The number showing a reduction of 20% that were judged fracture-free was reduced from 15 to 9. In the subset of subjects for whom the spine-film distance was known, the reduction in false positives was similar, whichever method was used to correct for magnification. There was no difference in the number of confirmed incident fractures detected when magnification correction by either method was employed. It is concluded that correcting for magnification differences using the statistical method outlined here reduces the number of false positive deformities very substantially and by a similar extent as correcting the magnification using reliable, measured spine-film and film-focus distances. A further advantage of this method is that it can be used retrospectively.

Three-year follow-up of the use of transdermal 17beta-estradiol matrix patches for the prevention of bone loss in early postmenopausal women

OBJECTIVE

A total of 325 of 569 postmenopausal women who were initially recruited into two 2-year, double-blind, placebo-controlled, dose-ranging studies of a matrix transdermal formulation of 17beta-estradiol (Menorest) participated in open-label extensions for a third year.

STUDY DESIGN

Those patients originally randomly assigned to receive 17beta-estradiol continued active treatment with dosages of 25, 50, 75, or 100 microg/d, whereas those originally randomly assigned to receive a placebo patch were switched to an active patch of identical size that delivered 17beta-estradiol at 25, 50, 75, or 100 microg/d. Follow-up was conducted, and bone density and other parameters were compared.

RESULTS

Overall, gains in bone mass were maintained in patients who received 3 years of active treatment. In patients originally randomly assigned to receive placebo, initial losses in bone mass during the first 2 years were reversed and replaced with marked increases after the switch to active treatment. All patients who had initially received placebo showed significant, dose-related, clinically relevant increases (2.77% +/- 0.99%; P =.0048; to 7.36% +/- 0.74%; P =.0001) in lumbar spine bone mineral density relative to the end of the second year of the original study; smaller final-year increases were noted among the patients who had been actively treated for all 3 years. Similar trends were reported for femoral, trochanter, and total hip bone mineral densities. Mean total body bone mineral density either increased or remained unchanged in all dosage groups. These results were accompanied by parallel changes in levels of serum and urinary markers of bone turnover, with all markers approaching or returning to premenopausal levels by month 36. The high tolerability of this formulation during years 1 and 2 was maintained during year 3; 5.5% of patients withdrew from treatment because of adverse events in the final year.

CONCLUSION

The Menorest formulation of transdermal 17beta-estradiol maintained bone mineral density gains in postmenopausal women and was well tolerated through a 3-year treatment period. It was also effective in reversing the initial bone loss associated with late commencement of therapy.

Bone-muscle strength indices for the human lower leg

This cross-sectional study is based on images from the lower leg as assessed by peripheral quantitative computer tomography (pQCT). Measurements were performed in 39 female and 38 male control subjects and 15 female professional volleyball players, all between 18 and 30 years of age. The images were obtained at shank levels of 4%, 14%, 33%, and 66% from the distal end. Bone and muscle cross-sectional areas, and the bones' density-weighted area moment of resistance and of inertia were assessed. From these, muscle-bone strength indices (MBSIs) were developed for compression (CI = 100. bone area/muscle area) and bending (BI = 100. bone area moment of resistance/muscle area/tibia length). Significant correlations between muscle cross-sectional area and bone were found at all section levels investigated. The strongest correlation for compression was observed in the sections at 14% (correlation coefficient r = 0.74), where 4.10 +/- 0.46 cm(2) bone, on average, was related to 100 cm(2) muscle. The compression index (CI) at the 14% level was independent of the tibia length. Interestingly, the 15 athletes had significantly greater CIs than the control subjects. This is most probably due to the greater tension development in the athletes. The highest correlation for bending was for anteroposterior bending at 33% of tibia length (r = 0.81), where the area moment of resistance, R, was on, average, 4.21 +/- 0.54 cm(3)/100 cm(2) muscle/m tibia length. Analysis of the bones' area moment of inertia showed that buckling is a possible cause of bending at the 33% and 66% levels, but not at the 14% level. No gender differences in MBSI were found. Likewise, age was without significant effect. The data show that bone architecture depends critically on muscle cross section and tension development. Moreover, bone geometry (e.g., the tibia length) influences the geometrical distribution of bone mineral, as it was found that long bones adapted to the same compressive strength are wider than short ones. We conclude that MBSIs offer a powerful diagnostic tool for bone disorders and may contribute to improving the treatment of bone metabolic and other diseases.

[Osteoporosis in the male]

BACKGROUND

Osteoporotic fractures occur frequently also in men. Epidemiologic data from Germany indicate that more than 900,000 men are affected by osteoporotic fractures. Diagnosis and therapy of male osteoporosis are hampered by a lack of clinical studies.

DIAGNOSIS

Risk factor analysis, conventional spine X-rays, bone densitometry and a limited number of serum and urine analyses contribute to the diagnosis of osteoporosis and the assessment of future fracture risk. Bone densitometry at the femoral neck is superior to measurements at the lumbar spine because of the high prevalence of degenerative changes at the lumbar spine in elderly men. Major risk factors for osteoporosis are hypogonadism, glucocorticoid therapy, hypercalciuria, gastrointestinal disease, and high alcohol consumption. In individual cases, bone histology or additional biochemical studies are needed to establish the cause of osteoporosis.

THERAPY

Calcium and vitamin D deficits should be substituted both in prevention and treatment of male osteoporosis. Testosterone replacement therapy is effective in hypogonadism. In primary osteoporosis and in corticosteroid-induced osteoporosis, bisphosphonates (cyclical etidronate, alendronate) and fluorides are therapeutic options.

CONCLUSION

Important principles in the care of men with osteoporosis are the transfer of knowledge established for postmenopausal osteoporosis and the rigorous search for secondary osteoporosis aiming at treatment of the underlying cause. Large prospective randomized trials aiming at the reduction of fracture rate in male osteoporosis are missing. They are urgently needed.

Acute physiological effects of exhaustive whole-body vibration exercise in man

Vibration exercise (VE) is a new neuromuscular training method which is applied in athletes as well as in prevention and therapy of osteoporosis. The present study explored the physiological mechanisms of fatigue by VE in 37 young healthy subjects. Exercise and cardiovascular data were compared to progressive bicycle ergometry until exhaustion. VE was performed in two sessions, with a 26 Hz vibration on a ground plate, in combination with squatting plus additional load (40% of body weight). After VE, subjectively perceived exertion on Borg's scale was 18, and thus as high as after bicycle ergometry. Heart rate after VE increased to 128 min-1, blood pressure to 132/52 mmHg, and lactate to 3.5 mM. Oxygen uptake in VE was 48.8% of VO2max in bicycle ergometry. After VE, voluntary force in knee extension was reduced by 9.2%, jump height by 9.1%, and the decrease of EMG median frequency during maximal voluntary contraction was attenuated. The reproducibility in the two VE sessions was quite good: for heart rate, oxygen uptake and reduction in jump height, correlation coefficients of values from session 1 and from session 2 were between 0.67 and 0.7. Thus, VE can be well controlled in terms of these parameters. Surprisingly, an itching erythema was found in about half of the individuals, and an increase in cutaneous blood flow. It follows that exhaustive whole-body VE elicits a mild cardiovascular exertion, and that neural as well as muscular mechanisms of fatigue may play a role.

Therapeutic equivalence of alendronate 70 mg once-weekly and alendronate 10 mg daily in the treatment of osteoporosis. Alendronate Once-Weekly Study Group

Dosing convenience is a key element in the effective management of any chronic disease, and is particularly important in the long-term management of osteoporosis. Less frequent dosing with any medication may enhance compliance, thereby maximizing the effectiveness of therapy. Animal data support the rationale that once-weekly dosing with alendronate 70 mg (7 times the daily oral treatment dose) could provide similar efficacy to daily dosing with alendronate 10 mg due to its long duration of effect in bone. In addition, dog studies suggest that the potential for esophageal irritation, observed with daily oral bisphosphonates, may be substantially reduced with once-weekly dosing. This dosing regimen would provide patients with increased convenience and would be likely to enhance patient compliance. We compared the efficacy and safety of treatment with oral once-weekly alendronate 70 mg (N=519), twice-weekly alendronate 35 mg (N=369), and daily alendronate 10 mg (N=370) in a one-year, double-blind, multicenter study of postmenopausal women (ages 42 to 95) with osteoporosis (bone mineral density [BMD] of either lumbar spine or femoral neck at least 2.5 SDs below peak premenopausal mean, or prior vertebral or hip fracture). The primary efficacy endpoint was the comparability of increases in lumbar spine BMD, using strict pre-defined equivalence criteria. Secondary endpoints included changes in BMD at the hip and total body and rate of bone turnover, as assessed by biochemical markers. Both of the new regimens fully satisfied the equivalence criteria relative to daily therapy. Mean increases in lumbar spine BMD at 12 months were: 5.1% (95% CI 4.8, 5.4) in the 70 mg once-weekly group, 5.2% (4.9, 5.6) in the 35 mg twice-weekly group, and 5.4% (5.0, 5.8) in the 10 mg daily treatment group. Increases in BMD at the total hip, femoral neck, trochanter, and total body were similar for the three dosing regimens. All three treatment groups similarly reduced biochemical markers of bone resorption (urinary N-telopeptides of type I collagen) and bone formation (serum bone-specific alkaline phosphatase) into the middle of the premenopausal reference range. All treatment regimens were well tolerated with a similar incidence of upper GI adverse experiences. There were fewer serious upper GI adverse experiences and a trend toward a lower incidence of esophageal events in the once-weekly dosing group compared to the daily dosing group. These data are consistent with preclinical animal models, and suggest that once-weekly dosing has the potential for improved upper GI tolerability. Clinical fractures, captured as adverse experiences, were similar among the groups. We conclude that the alendronate 70 mg once-weekly dosing regimen will provide patients with a more convenient, therapeutically equivalent alternative to daily dosing, and may enhance compliance and long-term persistence with therapy.

Detailed analyses of periarticular osteoporosis in rheumatoid arthritis

Periarticular osteopenia is the earliest radiographic sign of rheumatoid arthritis (RA). Recent studies using dual-energy X-ray absorptiometry (DXA) have indicated that the loss of periarticular BMD can be quantified by whole-hand bone mineral density (BMD) measurements. The aim of this study was to analyze periarticular BMD in more detail by DXA and quantitative ultrasound (QUS). In a cross-sectional study 23 women aged 30-76 years with early RA, mean disease duration 26 +/- 19 months, and 18 men aged 42-69 years, mean disease duration 24 +/- 25 months, were examined. All patients received antirheumatic therapy. The reference population consisted of 103 age-matched controls (68 females, 35 males) and young healthy controls. BMD measurements were performed using a DXA Expert XL densitometer (Lunar). BMD of the whole-hand and two subregions was determined: two subchondral regions of interest (S.CH.) were set within the trabecular bone, distal to the proximal interphalangeal joints of digits II and III excluding the dense subchondral bone of the metacarpophalangeal (MCP) joint and two metacarpal regions of interest (MCP) were set including the entire MCP joint of these fingers. QUS measurements at the proximal phalanges of digits II-V were performed using a DBM Sonic (Igea); amplitude-dependent speed of sound (Ad-SoS) was determined. In comparison with whole-hand BMD measurements, bone loss was pronounced in patients with a disease duration of 18-72 months at the subchondral regions of interest in both genders compared with age-matched controls (women: mean BMD loss S.CH. -23%, p<0.001, whole-hand -16%, p<0.001; men: mean BMD loss S.CH. -19%, p < 0.05, whole-hand -12%, p<0.05). The bone changes were also shown by QUS (women: Ad-SOS values of 1950 +/- 90 m/s in RA vs 2137 +/- 35 m/s in young healthy controls (p <0.005); men AD-SOS 1956 +/- 87 m/s in RA vs 2146 +/- 41 m/s in young healthy controls (p <0.05)). These results show that BMD and Ad-SOS values are significantly lowered in patients with early RA and indicate that periarticular osteoporosis in early RA might possibly be better detected using detailed hand scan analyses.

Sex difference in the validity of vertebral deformities as an index of prevalent vertebral osteoporotic fractures: a population survey of older men and women

Morphometric methods have been developed for standardized assessment of vertebral deformities in clinical and epidemiologic studies of spinal osteoporosis. However, vertebral deformity may be caused by a variety of other conditions. To examine the validity of morphometrically assessed vertebral deformities as an index of osteoporotic vertebral fractures, we developed an algorithm for radiological differential classification (RDC) based on a combination of quantitative and qualitative assessment of lateral spinal radiographs. Radiographs were obtained in a population of 50- to 80-year-old German women (n = 283) and men (n = 297) surveyed in the context of the European Vertebral Osteoporosis Study (EVOS). Morphometric methods (Eastell 3 SD and 4 SD criteria, McCloskey) were validated against RDC and against bone mineral density (BMD) at the femur and the lumbar spine. According to RDC 36 persons (6.2%) had at least one osteoporotic vertebral fracture; among 516 (88.9%) nonosteoporotics 154 had severe spondylosis, 132 had other spinal disease and 219 had normal findings; 14 persons (2.4%) could not be unequivocally classified. The prevalence of morphometrically assessed vertebral deformities ranged from 7.3% to 19.2% in women and from 3.5% to 16.6% in men, depending on the stringency of the morphometric criteria. The agreement between RDC and morphometric methods was poor. In men, 62-86% of cases with vertebral deformities were classified as nonosteoporotic (severe spondylosis or other spinal disease) by RDC, compared with 31-68% in women. Among these, most had wedge deformities of the thoracic spine. On the other hand, up to 80% of osteoporotic vertebral fractures in men and up to 48% in women were missed by morphometry, in particular endplate fractures at the lumbar spine. In the group with osteoporotic vertebral fractures by RDC the proportion of persons with osteoporosis according to the WHO criteria (T-score < -2.5 SD) was 90.0% in women and 86.6% in men, compared with 67.9-85.0% in women and 20.8-50.0% in men with vertebral deformities by various methods. Although vertebral deformities by most definitions were significantly and inversely related to BMD as a continuous variable in both sexes [OR; 95% CI ranged between (1.70; 1.07-2.70) and (3.69; 1.33-10.25)], a much stronger association existed between BMD and osteoporotic fractures defined by RDC [OR; 95% CI between (4.85; 2.30-10.24) and (15.40; 4.65-51.02)]. In the nonosteoporotic group individuals with severe spondylosis had significantly higher BMD values at the femoral neck (p < 0.01) and lumbar spine (p < 0.0004) compared with the normal group. On the basis of internal (RDC) and external (BMD) validation, we conclude that assessment of vertebral osteoporotic fracture by quantitative methods alone will result in considerable misclassification, especially in men. Criteria for differential diagnosis as used within RDC can be helpful for a standardized subclassification of vertebral deformities in studies of spinal osteoporosis.

Measurement imprecision in vertebral morphometry of spinal radiographs obtained in the European Prospective Osteoporosis Study: consequences for the identification of prevalent and incident deformities

Several algorithms are currently in use for evaluating vertebral deformities from plain lateral radiographs of the lumbar and thoracic spine. However, the effects of measurement imprecision as well as uncertainties over image magnification on the correct identification of prevalent and incident vertebral deformities with these algorithms has been little studied. In a pilot study for the European Prospective Osteoporosis Study (EPOS), plain radiographs were submitted to a single central evaluating centre for measurement of vertebral height from T4 to L4. The thoracic and lumbar spines were imaged on separate films, and we have assessed the precision of measurement of vertebral heights and height ratios. The standard deviation of the differences between films of each of three height measurements ranged from 1.1 to 1.2 mm. A two-stage strategy for identifying incident deformities was devised. This required that the vertebra be a prevalent deformity at the time of the second radiograph and also that at least one of the vertebral ratios should have changed significantly since the first radiograph. The second stage removed all but two of the 18 vertebrae flagged positive in the first stage but not considered to be certain incident fractures by clinical reading of the radiographs.

Alendronate increases bone density and bone strength at the distal radius in postmenopausal women

In addition to the alendronate Osteoporosis Intervention Trial (FOSIT) core protocol 901-0A of 1908 enrolled patients, the use of peripheral quantitative computed tomography (pQCT) was explored for the assessment of response to therapy. Bone mineral and strength related parameters at two different sites at the distal radius were explored in a subset of the multicenter core study. One hundred and three patients were entered into the substudy and given either a daily dose of 10 mg of alendronate or placebo for 1 year. Measurements were done at months 0, 3, 6, and 12. Inclusion criteria were bone mineral density (BMD) measurements at the lumbar spine of -2 SD. The response to therapy was assessed by dual-energy X-ray absorptiometry in the lumbar spine and the hip, and by pQCT in the ultradistal and the shaft sites of the radius. In line with the FOSIT core study, alendronate increased BMD at the lumbar spine and the hip, and it decreased the serum biochemical markers of bone turnover. The substudy showed differences between the therapy and placebo group in trabecular bone density (8.4%, p = 0.095), in total density (6.8%, p = 0.009), and in the bone strength index (BSI) (15. 6 mm3, p = 0.037) at the ultradistal site due to treatment and no changes at the radius shaft. A significant correlation was observed between percentage changes from baseline in BMD of the lumbar spine, and in total density and bone strength at the ultradistal radius site in the treatment group, but not in the placebo group. Thus, the ultradistal radius site did respond to alendronate therapy. The increased bone density accompanied a significant gain in the BSI at the ultradistal site, a finding that might help explain the reduced wrist fractures in the alendronate Fracture Intervention Trial.

Muscle and bone-aging and space

One of the major concerns of aging, but also during and after spaceflight, is loss of muscle and bone mass. In aging, this is associated with an increasing risk of fractures. Recently, the possibility of aged and aging astronauts has been arisen. Thus considering the perspectives of aging and space we want to discuss, in how far the adaptations during spaceflight and during aging interfere. In other words: does spaceflight push the astronauts along the irreversible axis of aging? And which of the spaceflight effects will be reversible? Bones adapt to their mechanical function. For convenience, a simple model has been proposed: Bone, as a 'mechanostat', keeps the strains within certain thresholds, namely one threshold for modeling, i.e. formation of new bone, and one for remodeling, i.e. repair and removal. These thresholds are usually expressed as strains. A crucial role in physiological strain detection is obviously played by the osteocytes. The largest forces in the musculo-skeletal systems arise from muscle contractions. The reason for this are the poor levers, against which the muscles pull. For example: during a one-leg vertical jump, a young subject (body weight 70 kg) exerts a vertical ground reaction force of 2500 N. Due to the lever ratio of os calcis and forefoot around the tibio-talar joint, the calf muscles must exert a force 3 times greater, so that together with the body weight the bones of the lower leg are loaded with 10000 N, i.e. 14 times the body weight. Accordingly, good correlations can be observed between muscle strength and bone strength, or muscle mass and bone mass. It is therefore reasonable to discuss the accumulated knowledge about loss of muscle and bone in a combined approach. In this respect, two points must be considered: (i) for structural adaptation of bone, the muscular variable of interest arc force and rate of force development, but not power, and (ii) women before menopause have a greater bone to muscle ratio than men.

A dose-ranging trial of a matrix transdermal 17beta-estradiol for the prevention of bone loss in early postmenopausal women. International Study Group

This international, randomized, double-blind, placebo-controlled, parallel group, dose-ranging trial was designed to determine the efficacy of 2 years of therapy with a new matrix transdermal 17beta-estradiol (Menorest) in preventing bone loss in early postmenopausal women, and to identify an appropriate dose. Two hundred ninety-two ambulatory women with natural or surgical menopause for 1-6 years were randomized to receive patches delivering 17beta-estradiol 50, 75, or 100 microg/day twice weekly for 25 days per 28 day cycle (with dydrogesterone 10 mg twice daily from days 11 to 24) or placebo, for 24 months. The primary outcome measure was the percentage change from baseline in lumbar spine bone mineral density (BMD) at 2 years. Secondary endpoints were percentage changes from baseline in three sites of proximal femur BMD and total body BMD, and in biochemical bone turnover markers. At 2 years, the difference from placebo in percentage change from baseline of L1-4 spine BMD was 6.2%, 7.6%, and 7.8% in the 50, 75, and 100 microg/day groups, respectively. Lumbar spine bone increased in 65.5%, 76.8%, and 81.0% of patients in the respective active treatment groups, compared with 4.9% on placebo. BMD increased significantly relative to placebo in the femoral neck, trochanter, total hip, and total body. Serum osteocalcin, bone alkaline phosphatase and urinary type I collagen C-telopeptide decreased significantly and dose dependently in 17beta-estradiol patients vs. placebo. For example, at 2 years, the difference between placebo and the 50 microg/day group, expressed in percentage change from baseline, was 3.25% at the femoral neck, 3.92% at the trochanter, 3.52% for total hip, and 2.40% for the total body. Breast pain and skin reactions were more common in the actively treated groups, but tolerability was generally good. Therefore, after 2 years, 17beta-estradiol was well-tolerated and highly effective at doses of between 50 and 100 microg/day in preventing bone loss and reducing bone turnover in early postmenopausal women. The dose of 50 microg/day, the lowest dose tested, is a suitable dose. There was little clinical benefit of increasing the dosage from 75 to 100 microg/day.

Serum leptin levels, body fat deposition, and weight in females with anorexia or bulimia nervosa

The objective of this retrospective study was to investigate the relation between serum leptin level and fat deposition in patients with eating disorders. 40 female inpatients with anorexia (n=24) or bulimia nervosa (n=16) were assessed for leptin level, body mass index (BMI), and percentage body fat by dual-energy X-ray absorbometry (DXA). The results show that percentage body fat is a better predictor for leptin level and clinical findings in eating disordered patients than BMI. We discuss the necessity for DXA measurements in anorectic patients for prognostic and research purposes.

Improved in vitro stability of serum osteocalcin by using a new commercially available antiproteolytic compound

The effect of a commercially available antiproteolytic compound (OSCAstabil) on the degradation in vitro of serum osteocalcin (Oc) was investigated in serum samples stored at 22, 4 or -30 degrees C (n = 20) or subjected to repeated freeze-thaw cycles (n = 8). The addition of the stabilizing agent immediately after serum preparation increased the Oc stability from < 3 to 6 h at 22 degrees C, from < 3 h to 3 days at 4 degrees C and from 1 day to more than 3 days at -30 degrees C. Up to three freeze-thaw cycles had no influence on the Oc stability, either with or without the stabilizer. The obviously prolonged Oc stability at 22 and 4 degrees C offers a more convenient and reliable Oc estimation procedure for clinical practice. The use of this antiproteolytic agent can be recommended in order to retard the in vitro degradation of serum Oc, not only for clinical routine, but also for studies on metabolic bone diseases.

Bone density reduction in various measurement sites in men and women with osteoporotic fractures of spine and hip: the European quantitation of osteoporosis study

We have measured bone mineral density (BMD) using dual X-ray absorptiometry (DXA) of the spine and hip, spinal quantitative computed tomography (QCTspi), and peripheral radial quantitative computed tomography (pQCTrad) in 334 spine and 51 hip fracture patients. The standardized hip and spine BMD for each patient was calculated and compared with the combined reference ranges published previously, each densitometer having been cross-calibrated with the prototype European Spine Phantom (ESPp) or the European Forearm Phantom (EFP). Male and female fracture cases had similar BMD values after adjusting for body size, where appropriate. This suggests that the relationship between bone density (mass per unit volume) and fracture risk is similar between men and women. However, compared with age-matched controls, mean decreases in BMD ranged from 0.78 SD units (women with hip fracture, DXAspi) to 2.57 SD units (men with spine fractures, QCTspi). The proportion of spine and hip fracture patients falling below the cutoff for osteoporosis (T-score <-2.5 SD) proposed by the World Health Organization (WHO) study group varied according to different BMD measurement procedures (range 18-94%). This finding suggests that the WHO definition requires different thresholds when used with non-DXA BMD measurement techniques. Receiver operator characteristic (ROC) analysis was used to compare measurement techniques for their ability to discriminate between cases and controls. Among DXA sites, the proximal femur was preferred when evaluating generalized bone loss, particularly in elderly people. An additional spinal BMD measurement may add clinical value if spine fracture risk assessment has a high priority. Both axial and peripheral QCT techniques performed comparably to DXA in spinal osteoporosis, so investigators and clinicians may use any of the three technologies with similar degrees of confidence for the diagnosis of generalized or site-specific bone loss providing straightforward clinical guidelines are followed.

Comments on the hypotheses underlying fracture risk assessment in osteoporosis as proposed by the World Health Organization

It was shown in a recent multivariate analysis of lumbar vertebral (L1-L3) CT scans of 171 women without fractures and 57 fractures somewhere in their skeletons, that regional assessment of the spinal mineral distribution can result in the discrimination of the above patient groups with an accuracy of about 90%. This level of discrimination was possible even in those cases with bone densities below the fracture threshold, where the overlap of patients with and without fractures is the greatest and clinically the most significant. In this region this new analytical technique could also identify a subgroup of patients who not yet had a fracture, but for whom all three lumbar vertebrae were classified as osteoporotic. From these results it follows that the osteoporosis model proposed by the World Health Organization (WHO), which assumes that fragility depends only on a single mean value of bone mineral density (BMD) for a patient, is overly simplistic and requires upgrading to include indices representing the distribution of bone mineral.

[Bone densitometry by dual energy methods]

Osteoporosis is mainly diagnosed by means of bone densitometry. Dual X-ray absorptiometry examinations represent the basis for a highly reproducible and correct measurement. At present, densitometry is the only method at our disposal capable of assessing material-related fracture risk. The calculation of general fracture risk is dependent on a number of varios factors and is, therefore, not to be deduced from bone density values only. Reference values are necessary in order to estimate bone strength. The most sensible way to achieve this is to compare measured values with a normal, healthy population (T score). Material-related fracture risk increases with the decrease of bone density.

[Normal values of vertebral heights in a representative population survey in Hungary]

The authors' aim was to derive Hungarian normal vertebral heights, height ratios and threshold values. The mean -3 SD of these ratios give them the threshold values for defining normal vertebraes. They examined the standardized vertebral morphometric measurements obtained in a cross-sectional population survey. Radiographs were taken according to standardized protocol and morphomeric measurements of anterior, central and posterior heights from thoracic 4 to lumbar 4 were made with a semiautomatic technique. The anterior, central, posterior I and posterior II height ratios were calculated for each vertebra. The mean and standard deviation of these ratios for each sex were derived using a statistical procedure to normalize the distribution. From the normally distributed vertebral height ratios the mean and standard deviation give us the threshold values for defining normal vertebraes. Anterior and central vertebral height ratios were smaller in males than females. The authors compared the ratios and threshold values in different European centers using the same method. The data confirm that vertebral height ratios vary between and within populations and the authors suggest that normal values for vertebral height ratios should be derived separately for males and females at each vertebral level. Having the normal values the knowledge of the Hungarian normal vertebral height ratios gives the possibility to carry on multicentre clinical, therapeutic and epidemiologic studies of vertebral deformity in Hungary. The authors suggest the widespread use of morphometry to evaluate vertebral osteoporosis because it can be done in every radiology unit, it is a cheap and easy method for measuring the bone mineral content.

Fractal analysis of proximal femur radiographs: correlation with biomechanical properties and bone mineral density

Conventional radiography and fractal analysis were used to quantify trabecular texture patterns in human femur specimens and these measures were used in conjunction with bone mineral density (BMD) to predict bone strength. Radiographs were obtained from 51 human femur specimens (25 male, 26 female). The radiographs were analyzed using three different fractal geometry based techniques, namely semi-variance, surface area and Fourier analysis. Maximum compressive strength (MCS) and shear stress (MSS) were determined with a material testing machine: BMD was measured using quantitative computed tomography (QCT). MCS and MSS both correlated significantly with BMD (MCS: R = 0.49-0.54; MSS: R = 0.69-0.72). Fractal dimension also correlated significantly with both biomechanical properties (MCS: R = 0.49-0.56; MSS: R = 0.47-0.54). Using multivariate regression analysis, the fractal dimension in addition to BMD improved correlations versus biomechanical properties. Both BMD and fractal dimension showed statistically significant correlation with bone strength. The fractal dimension provided additional information beyond BMD in correlating with biomechanical properties.

Multinational, placebo-controlled, randomized trial of the effects of alendronate on bone density and fracture risk in postmenopausal women with low bone mass: results of the FOSIT study. Fosamax International Trial Study Group

This randomized, double-masked, placebo-controlled trial evaluated the safety, tolerability and effects on bone mineral density (BMD) of alendronate in a large, multinational population of postmenopausal women with low bone mass. At 153 centers in 34 countries, 1908 otherwise healthy, postmenopausal women with lumbar spine BMD 2 standard deviations or more below the premenopausal adult mean were randomly assigned to receive oral alendronate 10 mg (n = 950) or placebo (n = 958) once daily for 1 year. All patients received 500 mg elemental calcium daily. Baseline characteristics of patients in the two treatment groups were similar. At 12 months, mean increases in BMD were significantly (p</=0.001) greater in the alendronate than the placebo group by 4.9% (95% confidence interval 4.6% to 5.2%) at the lumbar spine, 2.4% (2.0% to 2.8%) at the femoral neck, 3.6% (3.2% to 4.1%) at the trochanter and 3.0% (2.6% to 3.4%) for the total hip. The incidence of nonvertebral fractures was significantly lower in the alendronate than the placebo group (19 vs 37 patients with fractures), representing a 47% risk reduction for nonvertebral fracture for alendronate-treated patients (95% confidence interval 10% to 70%; p = 0.021). Incidences of adverse events, including upper gastrointestinal adverse events, were similar in the two groups. Therefore, for postmenopausal women with low bone mass, alendronate is well tolerated and produces significant, progressive increases in BMD at the lumbar spine and hip in addition to significant reduction in the risk of nonvertebral fracture.

Number and type of vertebral deformities: epidemiological characteristics and relation to back pain and height loss. European Vertebral Osteoporosis Study Group

Vertebral deformity is the classical hallmark of osteoporosis. Three types of vertebral deformity are usually described: crush, wedge and biconcave deformities. However, there are few data concerning the descriptive epidemiology of the individual deformity types, and differences in their underlying pathogenesis and clinical impact remain uncertain. The aim of this study was to compare the epidemiological characteristics of the three types of vertebral deformity and to explore the relationships of the number and type of deformity with back pain and height loss. Age-stratified random samples of men and women aged 50 years and over were recruited from population registers in 30 European centers (EVOS study). Subjects were invited to attend for an interviewer-administered questionnaire and lateral spinal radiographs. The presence, type and number of vertebral deformities was determined using the McCloskey-Kanis algorithm. A total of 13,562 men and women were studied; mean age in men was 64.4 years (SD 8.5), and in women 63.8 years (SD 8.5 years). There was evidence of variation in the occurrence of wedge, crush and biconcave deformity by age, sex and vertebral level. Wedge deformities were the most frequent deformity and tended to cluster at the mid-thoracic and thoraco-lumbar regions of the spine in both men and women. Similar predilection for these sites was observed for crush and to a lesser extent biconcave deformities though this was much less marked than for wedge deformities. In both sexes the frequency of biconcave deformities was higher in the lumbar than the thoracic spine and unlike the other deformity types it did not decline in frequency at lower lumbar vertebral levels. The prevalence of all three types of vertebral deformity increased with age and was more marked in women. There were no important differences in the effect of age on the different deformity types. All types of deformity were associated with height loss, which was greatest for individuals with crush deformity. Back pain was also associated with all types of deformity. Overall, these results do not suggest important differences in pathophysiology between the three deformity types. Biomechanical factors appear to be important in determining their distribution within the spine. All deformity types are linked with adverse outcomes, though crush deformities showed greater height loss than the other deformity types.

Age and dementia effect on neuropsychological test performance in very old age--influence of risk factors for dementia

In old age a large part of the variance in cognitive performance in population samples is explained by normal aging; in addition many subjects over 80 years are demented and therefore dementia also explains a part of cognitive variability. The question is whether the different factors for dementia (such as ApoE4, external atrophy parameter of the cranial computer tomography [cCT], education, sex or serum zinc level) influence the relation between age or dementia and Mini Mental State (MMSE) performance. In an epidemiological study data were analyzed of N = 239 subjects for the above factors. Most statistically significant variables of the MMSE do not change the amount of the partial correlation coefficient between the parameters age or dementia and MMSE. The external atrophy, however, diminishes the magnitude of the partial correlation between age and MMSE. In contrast the dementia-MMSE relation is unchanged. This points to a generally similar factor structure of cognitive aging and dementia in old age, but differences exist with respect to the importance of the external atrophy parameter of the brain. Most factors investigated explain separate parts of variance of cognitive performance in old age.

Measures of complexity for cancellous bone

The problem of quantifying the structure of cancellous bone has been addressed in the past by histomorphometry and more recently by imaging techniques using X-ray attenuation. The current approaches compute and describe parts of the construction of the trabecular net. We developed a new technique which quantifies cancellous bone of human lumbar vertebrae as a whole. The interactions, transactions, and interrelationships of all parts of the structural composition of the trabeculae are accounted for and quantified. The method is based on the concept of structural complexity within the framework of nonlinear dynamics. The methodology was developed by using axial high resolution computed tomography images. The technique was transferred to quantitative computed tomography images and is based on the non-invasive assessment of 50 human L3 specimens. The value of Houndsfield units per pixel representing trabecular bone of the vertebrae was transformed into color-encoded and alphabet-encoded symbols. The procedure of transformation of the X-ray attenuation pixels into symbols was necessary as a basis on which measures of complexity were introduced to assess the composition of symbols within the images. The development of a generalization of symbolic dynamics, a mathematical method, to work with two-dimensional images was a prerequisite. The results of this study demonstrate that the structural composition of cancellous bone declines more rapidly than bone mineral density during the loss of bone. This outcome strongly suggests an exponential relationship between bone mineral density and the architectural composition of cancellous bone. Normal trabecular bone has a complex ordered structure. The structural composition during the osteopenic phase of bone loss is characterized by lower structural complexity and a significantly higher level of architectural disorder. A high grade of osteoporosis leads again to an ordered structure, although its structural complexity is minimal.

Placebo-controlled multicenter study of oral alendronate in postmenopausal osteoporotic women. FOSIT-Study-Group. Fosamax International Trial

OBJECTIVES

To evaluate effects on bone mineral density (BMD), safety, and tolerability of a single daily dose of alendronate (10 mg), administered for 1 year to postmenopausal women with osteoporosis.

METHODS

This interim analysis includes the first approximately 20% of patients to complete treatment in a large, placebo-controlled study (the Fosamax International Trial (Fosit)), which enrolled 1908 patients from 34 countries. Patients < or = 85-year-old with osteoporosis (lumbar spinal BMD > or = 2 S.D. below mean for mature premenopausal Caucasian women) were randomly assigned to treatment with alendronate or placebo once daily in the morning; all patients received supplemental calcium (500 mg/day). Dual-Energy X-ray Absorptiometry (DXA) was used to measure BMD in spine and proximal femur.

RESULTS

A total of 297 patients had BMD data available for analysis. Patients treated with alendronate showed progressive increase of BMD during treatment. At 12 months, mean BMD had increased significantly (P < 0.001) at the lumbar spine (5.6%), trochanter (3.6%), and femoral neck (2.6%) in the alendronate group. Increases in BMD were significantly (P < 0.001) greater than in the placebo group at all sites. Among 442 patients assessed for safety, there were no statistically or clinically significant differences between treatment groups in the incidence of adverse events, including upper gastrointestinal adverse events, or laboratory abnormalities.

CONCLUSIONS

Results of this multinational study show that oral alendronate, administered as 10 mg once daily for 1 year, is generally well tolerated and produces significant, progressive increases in BMD at the lumbar spine and proximal femur of postmenopausal women with osteoporosis.

An anthropomorphic phantom study on the effect of midvertebral slice placement and region-of-interest positioning on the reproducibility of single-energy quantitative CT (QCT) of the spine

PURPOSE

The purpose of our study was to develop an anthropomorphic phantom with a 3D external reference system capable of geometrically describing the region of interest (ROI) of single-energy quantitative CT (QCT) scans and to study the reproducibility of ROI placement (volume) and bone mineral density (BMD) after operator-defined and algorithm-supported midvertebral slice (MVS) placement.

METHOD

In three vertebrae (L1-3) of 10 human cadaveric spines placed in a water phantom, MVSs were defined by an operator and an algorithm-supported technique on lateral digital CT radiographs, and QCT scans were performed accordingly. The measurements were repeated once after repositioning the phantom on the CT table. ROIs of the trabecular bone were determined with a standard technique. The percentage of bone volume was calculated for one ROI not covered by the repetition (volume mismatch percent).

RESULTS

Reproducibility with algorithm-supported MVS placement was superior to that of operator-defined positioning with regard to volume mismatch (mean +/- SD): 10.6+/-8.4 vs. 7.9+/-5.3%; and mean of paired BMDs (mean of three vertebral bodies): 2.7 vs. 1.5% (p < 0.05).

CONCLUSION

The ROI volume mismatch of repeated QCT scans, which is approximately 10% of ROI volume, can be quantified with an external reference system. Automated placement is superior to the manual technique and should be used in clinical practice.

Linearity and accuracy errors in bone densitometry

This investigation was undertaken to quantify accuracy errors and identify possible linearity errors in dual energy X-ray absorptiometry (DXA) of bone, based on studies of commercially available bone densitometers for planar densitometry. The following was found in a combination of in vitro phantom studies and in vivo investigations of human volunteers: (1) Pronounced differences between the instruments when measuring vertebral size and contours of the projected bone regions. (2) Falsely low bone mineral content (BMC in terms of g) in cases of low nominal bone mass, due to the fact that edge regions were omitted by the calculation software of some devices. (3) An increase in the projected bone area secondary to an increase in nominal bone mass with some instruments. (4) Clinically and statistically significant errors of accuracy of BMC and to a lesser extent bone mineral density (BMD). (5) Substantial linearity errors with some osteodensitometers for BMC, a phenomenon that reduces the usefulness of this parameter. It is concluded that DXA devices are affected by a combination of accuracy errors and linearity errors, some more than others, and that linearity errors influence their ability to monitor change in BMC and to a lesser extent in BMD, making system intercomparison difficult.

Effects of menstrual history and use of medications on bone mineral density: the EVOS Study

We have previously shown considerable between-center variation in bone mineral density (BMD) in the 13 EVOS centers that performed bone densitometry on their sex- and age-stratified population samples, after adjusting for weight and age. We have now investigated whether part of the between-center variability may be attributed to between-center variations in the use of medications. Information was collected from 2088 women and 1908 men at baseline on whether the subjects had ever been prescribed calcium, calcitonin, anabolic steroids, fluoride, vitamin D, or glucocorticoids and, for the women, whether they had ever used the oral contraceptive pill (OCP) or hormone replacement therapy (HRT). Each of these variables was fitted into a regression model adjusted for age, height, weight, and center. Only OCP and HRT significantly affected BMD. Those who had ever used OCPs had spinal BMD 0.029 g/cm2 greater than those who had never used them. Users of HRT had higher BMD than nonusers: 0. 037 g/cm2 at the spine, 0.018 g/cm2 at the trochanter, and 0.018 g/cm2 at the femoral neck. As expected, there was a great variation between centers in the use of OCP and HRT, but there were no significant correlations between mean BMD at any site in a given center and the prevalence of OCP or HRT use in that center. The between-center variance in BMD at all three sites remained highly significant after adjusting for treatment (P < 0.001). We conclude that HRT and OCP use are associated with moderate increases in BMD. The geographical variability of BMD in Europe was not explained by treatment with pharmaceuticals.

Bone densitometry: applications in sports-medicine

Physical exercise and sports increase muscular mass and the remodelling process of bones. The increment of bone depends on the type and the quality of sport. Short-term high-performance activities such as sprint, tennis, fencing lead to increased bone mineral density as well as weight lifting or heavy athletics. Swimming, bicycling, walking are associated with good musculature conditioning without an increase of bone mass. The effects on the bone by performing endurance activities are controversially discussed. Excessive sport leads to an increase of fatigue fractures. Low bone mass may result from hormonal disregulation in female athletes.

Measurements of vertebral shape by radiographic morphometry: sex differences and relationships with vertebral level and lumbar lordosis

OBJECTIVE

To examine sex-related and vertebral-level-specific differences in vertebral shape and to investigate the relationships between the lumbar lordosis angle and vertebral morphology.

DESIGN AND PATIENTS

Lateral thoracic and lumbar spine radiographs were obtained with a standardized protocol in 142 healthy men and 198 healthy women over 50 years old. Anterior (Ha), central (Hc) and posterior (Hp) heights of each vertebra from T4 to L4 were measured using a digitizing technique, and the Ha/Hp and Hc/Hp ratios were calculated. The lumbar lordosis angle was measured on the lateral lumbar spine radiographs.

RESULTS

Ha/Hp and Hc/Hp ratios were smaller in men than women by 1.8% and 0.7%, respectively, and these ratios varied with vertebral level. Significant correlations were found between vertebral shape and the lumbar lordosis angle.

CONCLUSIONS

These results demonstrate that vertebral shape varies significantly with sex, vertebral level and lumbar lordosis angle. Awareness of these relationships may help prevent misdiagnosis in clinical vertebral morphometry.

Orientation-dependent changes in MR signal intensity of articular cartilage: a manifestation of the "magic angle" effect

OBJECTIVE

To study magnetic resonance (MR) imaging pattern of normal hyaline articular cartilage in the knee joint with regard to the contribution of the "magic angle" effect to the MR signal.

DESIGN

Thirty-two healthy volunteers were imaged in a standard supine position in a 1.5-T unit using spin echo and gradient echo sequences. Nine volunteers were reimaged with the knee flexed. The signal behavior of the hyaline cartilage of the femoral condyles was evaluated qualitatively and quantitatively. The extended and flexed positions of the nine volunteers were compared.

RESULTS

A superficial and a deep hyperintense layer and a hypointense middle cartilage layer were observed. Segments of increased signal intensity were visible along the condyles; a magic angle effect on signal intensity was evident in the hypointense middle layer with both gradient echo and spin echo images.

CONCLUSION

The MR signal behavior of hyaline cartilage is influenced by the alignment of the collagen fibers within the cartilage in relation to the magnetic field. Failure to recognize this effect may lead to inaccurate diagnosis.

Prevalence of vertebral deformities according to the diagnostic method

Vertebral deformities are a major complication of osteoporosis. Although their prevalence is known to increase with age, the absence of reference criteria complicates their radiologic diagnosis. We evaluated variations in the prevalence of vertebral deformities according to the diagnostic method used in 291 men and 262 women older than 50 years included in the European Vertebral Osteoporosis Study. Lateral radiographs of the thoracic and lumbar spine were obtained in all subjects using standardized parameters. Six morphometric and quantitative methods were used to detect vertebral deformities. The prevalence of vertebral deformities, the number of vertebral deformities per 100 subjects and the prevalence of deformities for each vertebra varied according to the method used. With most methods, the percentage of subjects with vertebral deformities and the number of vertebral deformities were similar among the men and among the women. In the women, the prevalence and the number of vertebral deformities increased with age; beyond 70 years of age, however, the prevalence remained stable with advancing age, although the number of deformities per patient increased. In men, the prevalence of vertebral deformities remained stable with advancing age, suggesting that osteoporosis was not the only cause of vertebral deformity in this group. In conclusion, the prevalence of vertebral deformities varies according to the diagnostic method used. In men, none of the six methods evaluated in this study adequately differentiates osteoporotic deformities from deformities due to other causes.