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Evaluation of the internal vertebral venous plexus, vertebral canal, dural sac, and vertebral body via nonselective computed tomographic venography in the cervical vertebral column in healthy dogs.

OBJECTIVE: To evaluate nonselective computed tomographic (CT) venography for evaluating the cervical internal vertebral venous plexus (IVVP), define the diameter and area dimensions of the IVVP, and determine the relationship between dimensions of the cervical IVVP and other vertebral components in medium-sized dogs. Animals-6 healthy dogs that weighed 18 to 27 kg. Procedure-Helical CT scans were performed from C1 to C7 before and after IV injection of contrast medium (480 mg of iodine/kg) and a continuous infusion (240 mg of iodine/kg). Image data were transferred to a CT workstation, and measurements were performed on displayed transverse images. Diameter and area measurements of the vertebral canal, dural sac, IVVP, and vertebral body were obtained at C3 to C7. RESULTS: Opacification of vertebral venous structures was achieved in all dogs with no adverse reactions. Sagittal diameters of the IVVP for C3 to C7 ranged from 0.6 to 3.2 mm. Transverse diameters ranged from 2.32 to 5.74 mm. The IVVP area represented 12.4% of the mean vertebral canal transverse area and 30.61% of the mean vertebral epidural space area. Area measurements of the IVVP were significantly correlated with vertebral canal area and dural sac area. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that nonselective CT venography is a safe, sensitive method for performing morphometric assessments of the cervical IVVP in dogs. Findings support the theory that there may be a physiologic or developmental relationship between cervical vertebral canal components.

Animals↗

Risk factors for vertebral deformities in men: relationship to number of vertebral deformities. European Vertebral Osteoporosis Study Group.

Recent epidemiological studies suggest a similar overall prevalence of vertebral deformity in men to that in women, though the influence of increasing age on the prevalence of vertebral deformity is less marked in men. However, most affected men have only a single or two vertebral deformities, which may be unrelated to osteoporosis. The aim of this study was to examine the role of risk factors, previously demonstrated to be associated with vertebral osteoporosis in females, in men with single/dual deformities compared to those with multiple deformities. Age stratified random samples of men aged 50 years and over were recruited from population registers in 30 European centers as part of the European Vertebral Osteoporosis Study (EVOS). Subjects had a lateral spinal radiograph and the presence of vertebral deformity was determined using the McCloskey algorithm. Lifestyle and other risk factor data were obtained from an interviewer-administered questionnaire. In all 6937 men with a mean age of 64.4 (SD = 8.5) years were studied of whom 738 (10.6%) subjects had one or two deformities, and 109 (1.6%) subjects had three or more deformities. There was a marked increase in the prevalence of multiple vertebral deformities with increasing age, but only a modest effect of age on the prevalence of single deformities. Associations between various risk factors for osteoporosis and vertebral deformity were analyzed separately in men with single/dual vertebral deformity from those with three or more deformities using logistic regression. After adjustment for age, there were statistically significant associations between the following risk factors and multiple deformities: previous hip fracture (odds ratio [OR] 10.5), lack of regular physical activity (OR 2.9), low body mass (OR 2.5), and previous steroid use (OR 2.3). By contrast, there were only weak associations with these same variables in males with single/dual deformities and, apart from poor self-reported general health, all of the 95% confidence intervals spanned unity. There was no difference in the reporting of very heavy levels of physical activity under the age of 50 years between men with single/dual deformities and those with multiple deformities. In conclusion, men with multiple deformities showed a similar pattern of risk factor association to those seen in women with vertebral deformity, in contrast to men with single/dual deformities.

Aged↗

[Effects of stimulation of the vertebral nerve around the proximal vertebral artery on pupil and the autonomic nervous system--a contribution to pathophysiology of Powers' intermittent vertebral artery compression syndrome].

In order to elucidate the pathophysiology involved in Powers' intermittent vertebral artery compression syndrome, the author investigated sympathetic and parasympathetic changes produced by stimulation of nerves around the proximal vertebral artery (the vertebral nerve) in anesthetized and immobilized cats. These changes were observed mainly through pupillary changes, pulse and blood pressure, evoked potentials in the lateral horn of the upper thoracic cord (centrum ciliospinale), in the cervical sympathetic trunk, and in the short ciliary nerve. Electrical stimulation of vertebral nerve and local application of K ion around the vertebral artery produced stimulus-dependent ipsilateral mydriasis; when stimulation of higher strength was applied pronounced ipsilateral and mild contralateral mydriasis and hypertension occurred. Electrical stimulation of perivascular tissue around the subclavian artery proximal to origin of the vertebral artery showed ipsilateral mydriasis; while on stimulating the distal subclavian, the costcervical, the omocervical and the internal thoracic arteries did not show any pupillary response. Neuronal discharges in the lateral horn of upper thoracic cord and in the cervical sympathetic trunk showed stimulus-dependent increases on stimulating the vertebral nerve; while, inhibitory responses were observed in the short ciliary nerve formed by parasympathetic nerve fibers. From the data available, it seems likely that the stimulation of periarterial neural structure of the vertebral artery produced sympathetic excitatory as well as parasympathetic inhibitory neuronal discharges simultaneously may probably be derived from the integrating autonomic center in the hypothalamus.

Animals↗

The inheritance of vertebral shape in the mouse. II. A study using Fourier analysis to examine the inheritance of patterns of vertebral variation in the cervical and upper thoracic vertebral column.

In this paper we continue an earlier study which examined shape differences between the cervical and upper thoracic vertebrae of 2 inbred strains of mice (CBA, C57BL) and their F1. Our earlier study showed that the amount of shape difference varied between different vertebrae, even from adjacent levels, and that the vertebrae of the F1s showed a degree of resemblance to one or other parental strain which varied from vertebral level to vertebral level. We have suggested that this variation from level to level may have evolutionary significance in that it demonstrates a degree of autonomy in the genetic control of vertebral morphology between successive levels and, as such, allows the possibility of a form of mosaic evolution. In this study we further consider the inheritance of vertebral morphology both in the above-mentioned and in other crosses: this time, however, we focus on the ways in which vertebral morphology changes from level to level and on any differences in patterns of metameric change between inbred strains and their offspring. Our findings indicate that the morphology of vertebrae shows a metameric gradation in shape and that the rates of shape change along the column can vary from region to region. Furthermore, the F1 between 2 inbred strains may follow the pattern of variation characteristic of one parent for several metameric segments at a time. Different crosses between different inbred strains indicate that many genes influence the pattern of metameric variation in the vertebral column and that these genes have different actions along the column.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Estimation of vertebral body strength by dual photon absorptiometry in elderly individuals: comparison between measurements of total vertebral and vertebral body bone mineral.

The aim of the present study was to investigate the predictive value of bone mineral measurements by dual photon absorptiometry (DPA) in vitro for strength and ash weight of lumbar vertebral bodies in elderly, otherwise nonselected individuals. The material comprised 46 individuals: 26 males (43-95 years) and 20 females (63-95 years) without malignant diseases. Spinal segments, including L2, L3, and L4, were removed en bloc at autopsy. Bone mineral content (BMC) measurements imitating the normal DPA procedure were performed on the segments suspended in a water bath. The segments were measured in toto (BMCT) and remeasured after removal of the posterior elements (BMCB). The second lumbar vertebral body (L2) was then dissected and sawed below the endplates to obtain samples with planoparallel ends before compression in a materials testing machine. Finally, the bone specimens were incinerated for ash weight estimations. BMCT showed significant correlations to vertebral body ash weight (r = 0.79), compressive strength (load, r = 0.69), and stress (load per unit area, r = 0.47). The correlations were improved by removing the posterior elements (BMCB-ash weight, r = 0.86, BMCB-load, r = 0.74, BMCB-stress, r = 0.49). Correction of BMC for differences in vertebral body height (BMC/cm) further increased the correlation coefficients (BMCB/cm-ash weight, r = 0.92, BMCB/cm-load, r = 0.78, BMCB/cm-stress, r = 0.55). We conclude that lumbar BMC is predictive for lumbar vertebral body compressive strength in vitro and ash weight. The correlation coefficient is improved by removing the posterior non-weight-bearing element.(ABSTRACT TRUNCATED AT 250 WORDS)

Absorptiometry, Photon↗

A randomized trial of sodium fluoride (60 mg) +/- estrogen in postmenopausal osteoporotic vertebral fractures: increased vertebral fractures and peripheral bone loss with sodium fluoride; concurrent estrogen prevents peripheral loss, but not vertebral fractures.

Postmenopausal Caucasian women aged less than 80 years (n = 99) with one or more atraumatic vertebral fracture and no hip fractures, were treated by cyclical administration of enteric coated sodium fluoride (NaF) or no NaF for 27 months, with precautions to prevent excessive stimulation of bone turnover. In the first study 65 women, unexposed to estrogen (-E study), age 70.8 +/- 0.8 years (mean +/- SEM) were all treated with calcium (Ca) 1.0-1.2 g daily and ergocalciferol (D) 0.25 mg per 25 kg once weekly and were randomly assigned to cyclical NaF (6 months on, 3 months off, initial dose 60 mg/day; group F CaD, n = 34) or no NaF (group CaD, n = 31). In the second study 34 patients, age 65.5 +/- 1.2 years, on hormone replacement therapy (E) at baseline, had this standardized, and were all treated with Ca and D and similarly randomized (FE CaD, n = 17; E CaD, n = 17) (+E study). The patients were stratified according to E status and subsequently assigned randomly to +/- NaF. Seventy-five patients completed the trial. Both groups treated with NaF showed an increase in lumbar spinal density (by DXA) above baseline by 27 months: FE CaD + 16.2% and F CaD +9.3% (both p = 0.0001). In neither group CaD nor E CaD did lumbar spinal density increase. Peripheral bone loss occurred at most sites in the F CaD group at 27 months: tibia/fibula shaft -7.3% (p = 0.005); femoral shaft -7.1% (p = 0.004); distal forearm -4.0% (p=0.004); total hip -4.1% (p = 0.003); and femoral neck -3.5% (p = 0.006). No significant loss occurred in group FE CaD. Differences between the two NaF groups were greatest at the total hip at 27 months but were not significant [p < 0.05; in view of the multiple bone mineral density (BMD) sites, an alpha of 0.01 was employed to denote significance in BMD changes throughout this paper]. Using Cox's proportional hazards model, in the -E study there were significantly more patients with first fresh vertebral fractures in those treated with NaF than in those not so treated (RR = 24.2, p = 0.008, 95% CI 2.3-255). Patients developing first fresh fractures in the first 9 months were markedly different between groups: -23% of F CaD, 0 of CaD, 29% of FE CaD and 0 of E CaD. The incidence of incomplete (stress) fractures was similar in the two NaF-treated groups. Complete nonvertebral fractures did not occur in the two +E groups; there were no differences between groups F CaD and CaD. Baseline BMD (spine and femoral neck) was related to incident vertebral fractures in the control groups (no NaF), but not in the two NaF groups. Our results and a literature review indicate that fluoride salts, if used, should be at low dosage, with pretreatment and co-treatment with a bone resorption inhibitor.

Adult↗

The prevalence of vertebral fracture amongst patients presenting with non-vertebral fractures.

INTRODUCTION: Despite vertebral fracture being a significant risk factor for further fracture, vertebral fractures are often unrecognised. A study was therefore conducted to determine the proportion of patients presenting with a non-vertebral fracture who also have an unrecognised vertebral fracture. METHODS: Prospective study of patients presenting with a non-vertebral fracture in South Glasgow who underwent DXA evaluation with vertebral morphometry (MXA) from DV5/6 to LV4/5. Vertebral deformities (consistent with fracture) were identified by direct visualisation using the Genant semi-quantitative grading scale. RESULTS: Data were available for 337 patients presenting with low trauma non-vertebral fracture; 261 were female. Of all patients, 10.4% were aged 50-64 years, 53.2% were aged 65-74 years and 36.2% were aged 75 years or over. According to WHO definitions, 35.0% of patients had normal lumbar spine BMD (T-score -1 or above), 37.4% were osteopenic (T-score -1.1 to -2.4) and 27.6% osteoporotic (T-score -2.5 or lower). Humerus (n=103, 31%), radius-ulna (n=90, 27%) and hand/foot (n=53, 16%) were the most common fractures. For 72% of patients (n=241) the presenting fracture was the first low trauma fracture to come to clinical attention. The overall prevalence of vertebral deformity established by MXA was 25% (n=83); 45% (n=37) of patients with vertebral deformity had deformities of more than one vertebra. Of the patients with vertebral deformity and readable scans for grading, 72.5% (58/80) had deformities of grade 2 or 3. Patients presenting with hip fracture, or spine T-score <or=-2.5, or low BMI, or with more than one prior non-vertebral fracture were all significantly more likely to have evidence of a prevalent vertebral deformity (p<0.05). However, 19.8% of patients with an osteopenic T-score had a vertebral deformity (48% of which were multiple), and 16.1% of patients with a normal T-score had a vertebral deformity (26.3% of which were multiple). Following non-vertebral fracture, some guidelines suggest that anti-resorptive therapy should be reserved for patients with DXA-proven osteoporosis. However, patients who have one or more prior vertebral fractures (prevalent at the time of their non-vertebral fracture) would also become candidates for anti-resorptive therapy-which would have not been the case had their vertebral fracture status not been known. Overall in this study, 8.9% of patients are likely to have had a change in management by virtue of their underlying vertebral deformity status. In other words, 11 patients who present with a non-vertebral fracture would need to undergo vertebral morphometry in order to identify one patient who ought to be managed differently. CONCLUSIONS: Our results support the recommendation to perform vertebral morphometry in patients who are referred for DXA after experiencing a non-vertebral fracture. Treatment decisions will then better reflect any given patient's future absolute fracture risk. The 'Number Needed to Screen' if vertebral morphometry is used in this way would be seven to identify one patient with vertebral deformity, and 14 to identify one patient with two or more vertebral deformities. Although carrying out MXA will increase radiation exposure for the patient, this increased exposure is significantly less than would be obtained if X-rays of the dorso-lumbar spine were obtained.

Absorptiometry, Photon↗

Severity of prevalent vertebral fractures and the risk of subsequent vertebral and nonvertebral fractures: results from the MORE trial.

Prevalent vertebral fractures and baseline bone mineral density (BMD) predict subsequent fracture risk. The objective of this analysis is to examine whether baseline vertebral fracture severity can predict new vertebral and nonvertebral fracture risk. In the randomized, double-blind 3-year Multiple Outcomes of Raloxifene Evaluation (MORE) trial, 7705 postmenopausal women with osteoporosis (low BMD or prevalent vertebral fractures) were randomly assigned to placebo, raloxifene 60 mg/day, or raloxifene 120 mg/day. Post hoc analyses studied the association between baseline fracture severity and new fracture risk in the placebo group and the effects of placebo, raloxifene 60 mg/day, and raloxifene 120 mg/day on new fracture risk in women with the most severe prevalent vertebral fractures (n = 614). Vertebral fracture severity was visually assessed using semiquantitative analysis of radiographs and categorized by estimated decreases in vertebral heights. Reported new nonvertebral fractures were radiographically confirmed. Baseline vertebral fracture severity predicted vertebral and nonvertebral fracture risk at 3 years. In women without prevalent vertebral fractures, 4.3 and 5.5% had new vertebral and nonvertebral fractures, respectively. In women with mild, moderate, and severe prevalent vertebral fractures, 10.5, 23.6, and 38.1% respectively had new vertebral fractures, whereas 7.2, 7.7, and 13.8% respectively experienced new nonvertebral fractures. Number of prevalent vertebral fractures and baseline BMD also predicted vertebral fracture risk, but the severity of prevalent vertebral fractures was the only predictor of nonvertebral fracture risk and remained a significant predictor after adjustment for baseline characteristics, including baseline BMD. In patients with severe baseline vertebral fractures, raloxifene 60 mg/day decreased the risks of new vertebral [RR 0.74 (95% Cl 0.54, 0.99); P = 0.048] and nonvertebral (clavicle, humerus, wrist, pelvis, hip, and leg) fractures [RH 0.53 (95% CI 0.29, 0.99); P = 0.046] at 3 years. To prevent one new fracture at 3 years in women with severe baseline vertebral fractures with raloxifene 60 mg/day, the number needed to treat (NNT) was 10 for vertebral and 18 for nonvertebral fractures. Similar results were observed in women receiving raloxifene 120 mg/day. In summary, baseline vertebral fracture severity was the best independent predictor for new vertebral and nonvertebral fracture risk. Raloxifene decreased new vertebral and nonvertebral fracture risk in the subgroup of women with severe vertebral fractures at baseline. These fractures may reflect architectural deterioration, independent of BMD, leading to increased skeletal fragility.

Aged↗

Intervertebral disc disorganisation and its relationship to age adjusted vertebral body morphometry and vertebral bone architecture.

Vertebral deformity, intervertebral disc disorganisation, and change to vertebral bone architecture are morphological features that are associated with low back pain. The purpose of this study was to examine the influence of the morphological disorganisation of the intervertebral disc on vertebral body shape indices and vertebral cancellous bone architecture. Lumbar spines, T12-S1, were collected from 27 cadavers. The motion segments T12-L1, L2-L3 and L4-L5 were selected for the study. There were 8 females aged 35-94 years and 19 males aged 20-90 years. An intervertebral disc grade signifying the severity of disc disorganisation was assigned to each disc using the macroscopic disc grading criteria of Hansson and Roos (Spine, 1981; 6:147-153.). Vertebral shape indices and vertebral body bone histomorphometric analyses were performed on the vertebral bodies. Where appropriate, data were age adjusted and the influence of morphological disc disorganisation on vertebral body deformity and cancellous bone architecture analysed. Increased vertebral body axial area and the ratio of vertebral body axial area to sagittal area were associated with an increase in vertebral deformity and disc disorganisation. This suggests that vertebral deformity that remains clinically silent in the general population is influenced by intervertebral disc disorganisation. Vertebral cancellous bone architecture undergoes change associated with increased disc disorganisation, consistent with increased vertebral deformity. Vertebral bodies adjacent to degenerate discs (Grade 4) showed increased BV/TV and Tb.Th and decreased BS/BV. This shows that disc disorganisation may modulate vertebral cancellous bone architecture such that it protects against age-related bone changes. In addition, vertebral body wedging and concavity are associated with smaller vertebral body size and vertebral body compression is associated with larger vertebral body size and compromised cancellous bone architecture.

Adult↗

Ex vivo estimation of thoracolumbar vertebral body compressive strength: the relative contributions of bone densitometry and vertebral morphometry.

The estimation of vertebral fracture risk in individuals with suspected osteopenia is commonly based on measurements of lumbar spine bone density. The efficacy of vertebral size and deformity, as assessed by vertebral morphometry, in the prediction of fractures has been less studied. In an ex vivo investigation the regional relationships between vertebral size, vertebral deformity, bone density and compressive strength throughout the thoracolumbar spine were examined. In 16 vertebral columns (T1-L5) the bone mineral content (BMC) and bone mineral density (BMD) of each segment were measured using lateral projection dual-energy X-ray absorptiometry, and the vertebral cancellous density (VCD) and mid-vertebral cross-sectional area (CSA) measured using quantitative computed tomography. Vertebral body heights were determined from mid-sagittal CT scans, and vertical height ratios calculated for each segment. The failure load and failure stress of the isolated vertebral bodies were determined using a material testing device. Separate analyses were performed for the upper (T1-4), middle (T5-8) and lower (T9-12) thoracic, and lumbar (L1-5) segments. In all regions, failure load was strongly correlated with BMD (r = 0.82-0.86), moderately correlated with VCD (r = 0.60-0.71) and vertebral height (r = 0.22-0.49), and poorly correlated with the height ratios (r = 0.04-0.33). Failure stress was best predicted by BMD (r = 0.73-0.78) and VCD (r = 0.70-0.78) but was poorly correlated with all morphometric variables (r = 0.01-0.33). The segmental correlations between BMD and VCD ranged form r = 0.49 to r = 0.79. For all regions, BMD and VCD were included in the stepwise regression models for predicting failure load and failure stress. Either the mid-vertebral height or CSA were included in all the failure load models, while mid-vertebral height was included in only one of the failure stress models. The results suggest that vertebral deformity and size (as assessed by vertebral morphometry) make only a minor contribution to the prediction of vertebral strength additional to that provided by bone densitometry alone. The consistent regional relationships between variables appear to support the practice of global fracture risk assessment based on lumbar spine densitometry.

Adult↗

Age-related changes in vertebral height ratios and vertebral fracture.

Because no gold standard for the definition of vertebral fracture exists, there has been controversy about whether mild vertebral deformities are truly fractures or simply normal variation in vertebral size and shape. The aim of this study was to assess the associations of mild variations of vertebral height ratios to definite vertebral fractures. In 479 Japanese women (aged 53.9 +/- 9.1 years) who visited our institute for a medical checkup, we performed lateral lumbar radiographs and morphometric parameters were derived by measuring the anterior (Ha), middle (Hm) and posterior (Hp) height of each vertebral body from T12 to L4. Vertebral height ratios, Ha/Hp, Hm/Hp or Hp/Hp' of adjacent vertebrae that were more than 3 SD different from vertebra-specific means of normative data were considered to indicate fractures. Forty-five women were diagnosed with at least one fracture. After excluding the subjects with vertebral fracture, we examined the associations of the variations in vertebral height ratios with age, anthropometric parameters and lumbar bone mineral density (BMD) measured by dual-energy X-ray absorptiometry. Vertebral height ratios, especially Hm/Hp in postmenopausal women, tended to decrease with age and were positively associated with BMD. No significant correlation was observed between anthropometric parameters and vertebral height ratios. Aged-related decrease in vertebral height ratios (Ha/Hp and Hm/Hp, each averaged from T12 to L4) was significant even after the correction for BMD. Mean values of height ratios of non-fractured vertebrae adjusted for age and BMD were significantly lower in postmenopausal women with vertebral fracture than in those without vertebral fracture. Logistic regression analysis showed that BMD and height ratios of non-fractured vertebrae were independent predictors of vertebral fracture risk. The results suggest that older women, and women with at least one obvious (3 SD) fracture, tend to have mild deformities which do not qualify using the 3 SD definition. These mild deformities may represent real consequences of osteoporosis, because they are more pronounced among women with obvious fracture.

Adult↗

Equivalent deficits in bone mass of the vertebral body and posterior processes in women with vertebral fractures: implications regarding the pathogenesis of spinal osteoporosis.

Reduced bone mass of the spine in women with vertebral fractures is attributed to excessive trabecular bone loss from the vertebral body. However, the measurement obtained by posteroanterior (PA) scanning includes the posterior processes and the vertebral body, each comprising about 50% of the total vertebral mass. Thus, the deficit in bone mass by PA scanning may be due to deficits in one or both of these structures. We asked two questions: (1) In healthy women, is the age-related diminution in bone mass of the vertebral body greater than the diminution at the posterior processes? (2) In women with vertebral fractures, is the deficit in bone mass at the vertebral body, the fracture site in spinal osteoporosis, greater than at the posterior processes? Bone mass of the posterior processes and vertebral body of the third lumbar vertebra was measured by lateral scanning using dual-energy X-ray absorptiometry (DXA). Compared with 27 premenopausal women, deficits in 27 postmenopausal women at the posterior processes and vertebral body, respectively, were 35.9 +/- 3.7 and 25.2 +/- 4.1% (p < 0.05); t score, -1.5 +/- 0.2 and -1.1 +/- SD (p = 0.09). Compared with the postmenopausal (age-matched) women, deficits in 21 women with vertebral fractures at the posterior processes and vertebral body, respectively, were 22.6 +/- 4.9 and 24.5 +/- 8.3% (p = NS); Z score, -0.8 +/- 0.2 and -0.8 +/- 0.3 (p = NS). In vivo the bone mass of the vertebral body as a percentage of the whole vertebra was 45.7 +/- 0.1 in premenopausal women, 48.9 +/ 1.9 in postmenopausal women, 51.5 +/- 1.1 in women with low bone mass but no fractures, 52.7 +/- 2.4 in women with vertebral fractures, and 51.9 +/- 2.5% in vitro, based on autopsy specimens from 19 postmenopausal women aged 65 - 95 years. The lower spinal bone density measured using PA scanning in women with spine fractures may not be due to excessive or disproportionate trabecular bone loss from the vertebral body because comparable deficits are found at the posterior processes. Whether these deficits are due to reduced peak bone mass, trabecular bone loss, cortical bone loss, or varying combinations of these mechanisms remains to be established.

Absorptiometry, Photon↗

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.

Aged↗

The degree of osteoporosis in patients with vertebral fracture and patients with hip fracture: relationship to incidence of vertebral fracture.

The most typical fracture that occurs in osteoporotic patients is a vertebral fracture, whereas hip fractures are thought to occur in the most severe osteoporotic patients. The purpose of this study was to compare the degree of osteoporosis between patients with vertebral fractures and patients with hip fracture by examining bone mineral density, biochemical markers of bone metabolism, and the incidence of vertebral fractures. Subjects were 50 female patients with vertebral fractures (VX) and 60 female patients with hip fracture (HX). Bone mineral densities (BMD) of the lumbar spine, femoral neck (Neck), and one-third of the radius were determined by DXA. Total and bone alkaline phosphatase, osteocalcin, N-MID osteocalcin, PICP, free deoxypyridinoline, and CTx were measured. All z-scores of BMD in the three areas of VX and HX patients were negative, meaning those BMDs were lower in VX and HX than a decade-matched normal reference. The z-score of Neck BMD was significantly lower in HX than in VX. Deoxypyridinoline and CTx were significantly higher in HX than in VX. N-MID osteocalcin was significantly lower in HX than in VX. VX and HX patients were divided into four subgroups according to the number of their vertebral fractures: VX, with a single fracture; VX, with multiple fractures; HX, without vertebral fractures: and HX, with vertebral fractures. VX with multiple fractures and HX with vertebral fractures had lower z-scores at all skeletal sites. HX with vertebral fractures had the lowest median z-score at spine and Neck, whereas HX without vertebral fractures had a low z-score only at Neck compared to VX with a single fracture. There was no significant difference in markers among the subgroups. The number of vertebral fractures was negatively correlated with z-scores of BMD at all three sites. We concluded that uncoupling between bone formation and resorption is greater in hip fractures than in vertebral fractures. Vertebral fractures are associated with general osteopenia of the total skeleton. We suggest that there are two types of osteoporosis in patients with hip fractures: one is that the bone mass of the femoral neck is specifically reduced, and the other is a terminal stage of osteoporosis which follows osteoporosis with vertebral fractures.

Aged↗

"Occult" osteoporotic vertebral fractures: vertebral body fractures without radiologic collapse.

STUDY DESIGN: Retrospective observational study. OBJECTIVES: We report our experience with patients who presented with osteoporotic vertebral fractures with no visible deformation of vertebral body. SUMMARY OF BACKGROUND DATA: The diagnosis of osteoporotic vertebral fractures largely relies on the observation of vertebral deformations on plain radiographs, termed vertebral collapses. There are no data on the characteristics, or indeed of the reality, of osteoporotic vertebral fractures with no significant deformation of the vertebral body. METHODS: We retrospectively analyzed cases that presented with acute back pain with no initial deformation of the vertebral body on plain radiographs, and later proved to be fresh osteoporotic vertebral body fractures. All cases met each of the following criteria: 1) The incriminated vertebra appeared normal on initial radiographs (Genant's Grade 0 deformation). 2) The diagnosis of fresh vertebral body fracture was confirmed by MRI. 3) The diagnosis of osteoporosis was made by the combination of established osteoporosis, ruling out of underlying disease, and follow-up. RESULTS: We observed 21 fractures in 16 patients (11 female/5 male; mean age, 72 years). Most of these fractures affected the lumbar spine (14 of 21 occurred at L2-L5). Osteoporosis was known beforehand in 9 patients and newly diagnosed in 7 patients. At follow-up, radiographs were obtained for 19 of 21 fractures: in 15 cases, the vertebral fracture developed a vertebral collapse (Genant's Grade > or = 0.5) in a mean of 12.5 weeks (range, 4-24 weeks); in the 4 remaining cases, the vertebra remained normal. All cases had a clinically favorable outcome. CONCLUSION: Osteoporotic vertebral fractures with no sign of vertebral collapse on initial radiographs do indeed exist. They are analogous to occult stress fractures well known in other skeletal sites. They must not be misdiagnosed as malignant lesions.

Adult↗

Epidemiology of vertebral fractures: implications for vertebral augmentation.

To put vertebral augmentation (eg, vertebroplasty) into perspective, the etiology and outcomes of vertebral fractures are reviewed. There is considerable debate about which criteria should be used to define a vertebral fracture because there is no consistent relation between symptoms and the degree of vertebral deformity. However, it is the more significant vertebral body deformities that are most closely associated with frequent or severe back pain, and the referrals for vertebral augmentation come mainly from this subset of patients. In addition to their vertebral fractures, these patients typically have osteoporosis or elevated bone turnover, and they are at greatly increased risk of subsequent fractures as a result of falling or, more often, excessive spinal loads from activities of everyday living. Additional risk factors for new vertebral fractures include the number and severity of vertebral deformities at baseline. Moreover, new fractures are most likely in nearby vertebrae, and they occur more frequently in the mid-thoracic or thoracolumbar regions of the spine. Interestingly, these are also the characteristics of the subsequent fractures of contiguous vertebrae considered by some to represent a complication of vertebral augmentation, yet they characterize vertebral fracture risk even in untreated patients. Vertebral fractures are very common among older men and postmenopausal women; they are associated with substantial morbidity and mortality; and they may have a devastating impact on the patient's quality of life. Vertebral augmentation may be able to help many of these patients, although opportunities exist to optimize management strategies with respect to the other factors that influence long-term outcomes in this patient population.

Comorbidity↗

Tortuosity of the vertebral artery in patients with cervical spondylotic myelopathy. Risk factor for the vertebral artery injury during anterior cervical decompression.

STUDY DESIGN: The case report presented herein shows tortuosity of the vertebral artery in a patient with cervical myelopathy. This case led the authors to evaluate 22 other patients who also had undergone anterior cervical fusion. They were studied before operation by either magnetic resonance imaging angiography or selective vertebral angiography. OBJECTIVES: To analyze the radiographs, computed tomography, magnetic resonance imaging, and angiography findings to detect any tortuosity of the vertebral artery in patients with cervical myelopathy to show the risk factors of vertebral artery injury during anterior decompression. SUMMARY OF BACKGROUND DATA: Complications of vertebral artery laceration during cervical anterior decompression are rare, so this injury and abnormality in the course of vertebral artery in patients with cervical myelopathy receive little attention. METHODS: The tortuosity of the vertebral artery was assessed by angiography, magnetic resonance imaging, and computed tomography. RESULTS: Mild vertebral artery tortuosity was observed in 10 patients and loop formation in three associated with cervical spondylotic changes. CONCLUSIONS: This study suggests that vertebral artery loop formation is developed associated with cervical spondylotic changes. During the anterior decompression of cervical spondylotic myelopathy or radiculopathy, the looped vertebral artery could be injured by an excessive wide rejection of the bone or disc material. In the case of vertebral artery migration, the looped vertebral artery can even be injured by routine procedures.

Adolescent↗

Association of severe vertebral fractures with reduced quality of life: reduction in the incidence of severe vertebral fractures by teriparatide.

OBJECTIVE: The association between vertebral fracture severity and health-related quality of life (HRQOL) was investigated in a subset of patients in the Fracture Prevention Trial. We sought to determine whether vertebral fracture severity was associated with HRQOL scores, and if so, to determine the effects of teriparatide (recombinant human parathyroid hormone 1-34) on vertebral fracture grades that most strongly impact HRQOL in postmenopausal women with osteoporosis. METHODS: Vertebral fracture severity was assessed by the visual semiquantitative (SQ) method. A subset of 444 patients with a baseline radiograph completed the Osteoporosis Assessment Questionnaire. Baseline HRQOL scores were modeled as a function of maximum baseline vertebral fracture grade, while controlling for age, bone mineral density, body mass index, and back pain. RESULTS: The effect of baseline vertebral fracture grade on baseline HRQOL was statistically significant, while interactions between vertebral fracture grade and the other variables were not statistically significant. SQ grade 3 (SQ3) vertebral fractures were associated with a significantly lower overall HRQOL score and with significantly lower physical function, symptoms, and emotional status dimension scores. After a median of 19 months of therapy, new or worsening SQ3 vertebral fractures occurred in 21 of 448 patients (4.7%) in the placebo group compared with 3 of 444 patients (0.7%) in the 20 mug/day teriparatide group. The risk of developing a new or worsened SQ3 vertebral fracture was reduced by 86% (P < 0.001) in patients treated with 20 mug/day teriparatide. CONCLUSION: Compared with prevalent fractures of lesser severity, SQ3 vertebral fractures were associated with reduced HRQOL. Teriparatide treatment significantly reduced the risk of new or worsening SQ3 vertebral fractures. These findings suggest, but do not directly demonstrate, a benefit of teriparatide on HRQOL.

Aged↗