Relationships between metacarpal morphometry, forearm and vertebral bone density and fractures in post-menopausal women

Sex and External Size Specific Limitations in Assessing Bone Health From Adult Hand Radiographs

Morphological parameters measured for the second metacarpal from hand radiographs are used clinically for assessing bone health during growth and aging. Understanding how these morphological parameters relate to metacarpal strength and strength at other anatomical sites is critical for providing informed decision-making regarding treatment strategies and effectiveness. The goals of this study were to evaluate the extent to which 11 morphological parameters, nine of which were measured from hand radiographs, relate to experimentally measured whole-bone strength assessed at multiple anatomical sites and to test whether these associations differed between men and women. Bone morphology and strength were assessed for the second and third metacarpals, radial diaphysis, femoral diaphysis, and proximal femur for 28 white male donors (18-89 years old) and 35 white female donors (36-89+ years old). The only morphological parameter to show a significant correlation with strength without a sex-specific effect was cortical area. Dimensionless morphological parameters derived from hand radiographs correlated significantly with strength for females, but few did for males. Males and females showed a significant association between the circularity of the metacarpal cross-section and the outer width measured in the mediolateral direction. This cross-sectional shape variation contributed to systematic bias in estimating strength using cortical area and assuming a circular cross-section. This was confirmed by the observation that use of elliptical formulas reduced the systematic bias associated with using circular approximations for morphology. Thus, cortical area was the best predictor of strength without a sex-specific difference in the correlation but was not without limitations owing to out-of-plane shape variations. The dependence of cross-sectional shape on the outer bone width measured from a hand radiograph may provide a way to further improve bone health assessments and informed decision making for optimizing strength-building and fracture-prevention treatment strategies. © 2022 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Preoperative measures of bone mineral density from digital wrist radiographs

Aims

Assessment of bone mineral density (BMD) with dual-energy X-ray absorptiometry (DXA) is a well-established clinical technique, but it is not available in the acute trauma setting. Thus, it cannot provide a preoperative estimation of BMD to help guide the technique of fracture fixation. Alternative methods that have been suggested for assessing BMD include: 1) cortical measures, such as cortical ratios and combined cortical scores; and 2) aluminium grading systems from preoperative digital radiographs. However, limited research has been performed in this area to validate the different methods. The aim of this study was to investigate the evaluation of BMD from digital radiographs by comparing various methods against DXA scanning.

Methods

A total of 54 patients with distal radial fractures were included in the study. Each underwent posteroanterior (PA) and lateral radiographs of the injured wrist with an aluminium step wedge. Overall 27 patients underwent routine DXA scanning of the hip and lumbar spine, with 13 undergoing additional DXA scanning of the uninjured forearm. Analysis of radiographs was performed on ImageJ and Matlab with calculations of cortical measures, cortical indices, combined cortical scores, and aluminium equivalent grading.

Results

Cortical measures showed varying correlations with the forearm DXA results (range: Pearson correlation coefficient (r) = 0.343 (p = 0.251) to r = 0.521 (p = 0.068)), with none showing statistically significant correlations. Aluminium equivalent grading showed statistically significant correlations with the forearm DXA of the corresponding region of interest (p < 0.017).

Conclusion

Cortical measures, cortical indices, and combined cortical scores did not show a statistically significant correlation to forearm DXA measures. Aluminium-equivalent is an easily applicable method for estimation of BMD from digital radiographs in the preoperative setting.

Cite this article: Bone Joint Res 2021;10(12):830–839.

The influence of bone loss on the three adult age markers of the innominate

To evaluate the influence of bone loss on the three adult age markers of the innominate, 30 males and 30 females aged between 16 and 80 years coming from the British Coventry collection were analyzed. The pubic symphysis, auricular surface, and acetabulum age variables were evaluated following the descriptions of Schmitt, Buckberry-Chamberlain, and Rissech, respectively. The second metacarpal cortical index was used to evaluate bone loss. Possible sexual differences in metrical variables were explored by a Student t-test taking into account the entire sample. The possible relationships between the cortical index and the three age methods' stages were assessed by the Kruskall-Wallis test and Spearman's correlation coefficient. There were no sexual differences in the cortical index. In general, we observed no significant differences between the cortical index in the different stages of the pubic symphysis, auricular surface, or acetabulum variables in men and women. Most correlation coefficients are negatives, and their absolute values are between 0.001 and 0.44, indicating an extremely low influence of bone loss on the analyzed variables. Our findings suggest little influence of bone loss in the three ageing methods. However, further research on this topic is necessary. This is the first study to analyze the influence of bone loss in the ageing changes undergone by the variables of the three adult age indicators of the innominate taking into account both sexes.

A new implementation of digital X-ray radiogrammetry and reference curves of four indices of cortical bone for healthy European adults

Digital X-ray radiogrammetry performs measurements on a hand radiograph in digital form. We present an improved implementation of the method and provide reference curves for four indices for the amount of bone. We collected 1662 hand radiographs of healthy subjects of age 9-100 years.

PURPOSE

The digital X-ray radiogrammetry (DXR) method has been shown to be efficient for diagnosis of osteoporosis and for assessment of progression of rheumatoid arthritis. The aim of this work is to present a new DXR implementation and reference curves of four indices of cortical bone and to compare their relative SDs in healthy subjects at fixed age and gender.

MATERIALS AND METHODS

A total of 1662 hand radiographs of healthy subjects of age 9-100 years were collected in Jena in 2001-2005. We also used a longitudinal study of 116 Danish children born in 1952 with on average 11 images taken over the age range 7 to 40 years. The new DXR method reconstructs the whole metacarpal contour so that the metacarpal lengths can be measured and used in two of the indices. The new DXR method automatically validates 97 % of the images and is implemented as a local server for PACS users.

RESULTS

The Danish bone health index (BHI) data are consistent with the Jena data and also with the published BHI reference for healthy children. BHI is found to have smaller relative SD than the other three indices in the Jena cohort over the age range 20-80 years.

CONCLUSION

The new DXR method is an extension of the existing BoneXpert method for children, which allows patients to be followed from childhood into adulthood with the same method. By making all four indices of cortical bone available within the same medical device, it becomes possible to decide which index has the best relation to fracture risk in future studies.

Moving toward a prevention strategy for osteoporosis by giving a voice to a silent disease

A major unmet challenge in developing preventative treatment programs for osteoporosis is that the optimal timing of treatment remains unknown. In this commentary we make the argument that the menopausal transition (MT) is a critical period in a woman's life for bone health, and that efforts aimed at reducing fracture risk later in life may benefit greatly from strategies that treat women earlier with the intent of keeping bones strong as long as possible. Bone strength is an important parameter to monitor during the MT because engineering principles can be applied to differentiate those women that maintain bone strength from those women that lose bone strength and are in need of early treatment. It is critical to understand the underlying mechanistic causes for reduced strength to inform treatment strategies. Combining measures of strength with data on how bone structure changes during the MT may help differentiate whether a woman is losing strength because of excessive bone resorption, insufficient compensatory bone formation, trabeculae loss, or some combination of these factors. Each of these biomechanical mechanisms may require a different treatment strategy to keep bones strong. The technologies that enable physicians to differentially diagnose and treat women in a preventive manner, however, have lagged behind the development of prophylactic treatments for osteoporosis. To take advantage of these treatment options, advances in preventive treatment strategies for osteoporosis may require developing new technologies with imaging resolutions that match the pace by which bone changes during the MT and supplementing a woman's bone mineral density (BMD)-status with information from engineering-based analyses that reveal the structural and material changes responsible for the decline in bone strength during the menopausal transition.

Comparison of radiogrammetrical metacarpal indices in children and reference data from the First Zurich Longitudinal Study

BACKGROUND

A number of radiogrammetrical metacarpal indices are in use, some of which have been adapted for children.

OBJECTIVE

The purpose of this study was to compare four known indices-bone mineral density (BMD), relative cortical area, Exton-Smith index, bending breaking resistance index-and the more recently defined pediatric bone index (PBI) according to the two criteria of minimum height dependence and minimum variability in children of equal bone age.

MATERIALS AND METHODS

A total of 3,121 left-hand radiographs from 231 healthy Caucasian children ranging in age from 3 to 19 years old were analysed using BoneXpert®, a programme for automatic analysis of hand radiographs and assessment of bone age.

RESULTS

Dependence on height for chronological age or bone age and the mean relative standard deviation were lowest in the PBI for both genders pooled. The differences in height dependence were statistically significant and are shown to be clinically relevant. Reference data for PBI are presented.

CONCLUSION

PBI may be a better indicator than BMD for bone health in children; however, verification in a clinical group is needed.

Identification of homogeneous genetic architecture of multiple genetically correlated traits by block clustering of genome-wide associations

Genome-wide association studies (GWAS) using high-density genotyping platforms offer an unbiased strategy to identify new candidate genes for osteoporosis. It is imperative to be able to clearly distinguish signal from noise by focusing on the best phenotype in a genetic study. We performed GWAS of multiple phenotypes associated with fractures [bone mineral density (BMD), bone quantitative ultrasound (QUS), bone geometry, and muscle mass] with approximately 433,000 single-nucleotide polymorphisms (SNPs) and created a database of resulting associations. We performed analysis of GWAS data from 23 phenotypes by a novel modification of a block clustering algorithm followed by gene-set enrichment analysis. A data matrix of standardized regression coefficients was partitioned along both axes--SNPs and phenotypes. Each partition represents a distinct cluster of SNPs that have similar effects over a particular set of phenotypes. Application of this method to our data shows several SNP-phenotype connections. We found a strong cluster of association coefficients of high magnitude for 10 traits (BMD at several skeletal sites, ultrasound measures, cross-sectional bone area, and section modulus of femoral neck and shaft). These clustered traits were highly genetically correlated. Gene-set enrichment analyses indicated the augmentation of genes that cluster with the 10 osteoporosis-related traits in pathways such as aldosterone signaling in epithelial cells, role of osteoblasts, osteoclasts, and chondrocytes in rheumatoid arthritis, and Parkinson signaling. In addition to several known candidate genes, we also identified PRKCH and SCNN1B as potential candidate genes for multiple bone traits. In conclusion, our mining of GWAS results revealed the similarity of association results between bone strength phenotypes that may be attributed to pleiotropic effects of genes. This knowledge may prove helpful in identifying novel genes and pathways that underlie several correlated phenotypes, as well as in deciphering genetic and phenotypic modularity underlying osteoporosis risk.

A paediatric bone index derived by automated radiogrammetry

SUMMARY

Hand radiographs are obtained routinely to determine bone age of children. This paper presents a method that determines a Paediatric Bone Index automatically from such radiographs. The Paediatric Bone Index is designed to have minimal relative standard deviation (7.5%), and the precision is determined to be 1.42%.

INTRODUCTION

We present a computerised method to determine bone mass of children based on hand radiographs, including a reference database for normal Caucasian children.

METHODS

Normal Danish subjects (1,867), of ages 7-17, and 531 normal Dutch subjects of ages 5-19 were included. Historically, three different indices of bone mass have been used in radiogrammetry all based on A = piTW(1 - T/W), where T is the cortical thickness and W the bone width. The indices are the metacarpal index A/W(2), DXR-BMD = A/W, and Exton-Smith's index A/(WL), where L is the length of the bone. These indices are compared with new indices of the form A/(W(a) L(b)), and it is argued that the preferred index has minimal SD relative to the mean value at each bone age and sex. Finally, longitudinal series of X-rays of 20 Japanese children are used to derive the precision of the measurements.

RESULTS

The preferred index is A/(W(1.33) L(0.33)), which is named the Paediatric Bone Index, PBI. It has mean relative SD 7.5% and precision 1.42%.

CONCLUSIONS

As part of the BoneXpert method for automated bone age determination, our method facilitates retrospective research studies involving validation of the proposed index against fracture incidence and adult bone mineral density.

Low metacarpal index predicts hip fracture: a prospective population study of 3,561 subjects with 15 years of follow-up

BACKGROUND

Metacarpal index (MCI), measured from hand radiographs as the ratio between combined cortical thickness and bone diameter, has been suggested for assessment of bone mass and risk of osteoporotic fracture. We studied MCI for its ability to predict hip fractures.

METHODS

Hand radiographs were taken and MCI determined in 3,561 subjects from a representative population sample of 8,000 Finns who were 30 years of age or over in 1978-80. Record linkage to the National Hospital Discharge Register identified 117 subjects who had been hospitalized for primary treatment of hip fracture by the end of 1994.

RESULTS

High age, low body mass index, tall stature and smoking at baseline showed, independently of each other, significant associations with low MCI. Low MCI was a strong predictor of hip fracture. When adjusted for all potential confounding factors, the relative risk of hip fracture per decrement of MCI by one standard deviation (0.1) was 1.5 (95% CI 1.2-1.8).

INTERPRETATION

Low MCI is associated with known risk factors of osteoporosis and predicts hip fracture. Since hand radiographs are easily available at low cost, measurements of MCI can be used as an alternative approach to find osteoporotic individuals with a high risk of hip fracture.

Age-related cortical bone loss in women from a 3rd–4th century AD population from England

Age-dependent cortical bone loss in adult females from a skeletal assemblage from 3rd-4th century AD England was studied using metacarpal radiogrammetry. Results showed reduced peak cortical bone thickness compared with modern subjects, and the magnitude of cortical bone loss in older females compared with their younger counterparts was greater than that documented for a modern reference population. An elevated prevalence of fractures classically associated with osteoporosis was also observed in the over-50-year cohort. The severity of osteoporosis in this group is difficult to explain in terms of extraneous factors relating to 3rd-4th century lifestyles. Given the important genetic component in osteoporosis, the results may indicate some inherent susceptibility in this particular population to the disease, and ways in which this possibility might be further explored are suggested.

Evaluation of bone-mineral density by digital X-ray radiogrammetry (DXR) in pediatric renal transplant recipients

BACKGROUND

Loss of bone mass and increased fracture risk are known complications after renal transplantation in adults. Risk factors include donor source, dialysis status prior to transplantation, aetiology of renal disease, transplant rejection and drug therapy, particularly steroids.

OBJECTIVE

In this preliminary study of quantification of bone loss in children after renal transplantion, we evaluated the applicability of digital X-ray radiogrammetry (DXR) of hand radiographs to estimate cortical bone mineral density (DXR-BMD).

MATERIALS AND METHODS

A total of 23 renal transplant recipients (9 girls, 14 boys; age 6.5-20 years, median 16.3 years) underwent DXR measurements for calculation of DXR-BMD and metacarpal index (DXR-MCI) using radiographs of the non-dominant left hand. The duration between transplantation and the DXR evaluation, the duration of dialysis and medication were considered. The results were compared to a local age-matched and gender-matched reference data base.

RESULTS

Our study revealed a significant decrease in bone mineral density compared to an age-matched and sex-matched normal population (P<0.05). In three patients the DXR-BMD was reduced more than -2.5 SD. In 12 patients the DXR-BMD was between -1 and -2.5 SD, and in 7 patients the DXR-BMD was in the normal range. In one patient, evaluation was not possible. Fractures were documented in three patients following transplantation. Reduced DXR-BMD was not significantly associated with immunosuppressive therapy or the duration of dialysis, and there was no significant correlation between DXR-BMD and the time between transplantation and DXR evaluation.

CONCLUSIONS

Paediatric renal transplant patients show reduced DXR-BMD. In this preliminary study we demonstrated that DXR-BMD seems to be a reliable technique for quantification of demineralisation following renal transplantation in children.

Estudio de la masa ósea en el síndrome de Turner

OBJECTIVES

To evaluate bone mass in patients with Turner syndrome by measuring metacarpal cortical thickness and bone diameter before and after treatment with oxandrolone, growth hormone (GH) and estrogens.

PATIENTS AND METHODS

We studied 42 girls with Turner syndrome divided into the following groups: group I: 31 patients aged between 3 and 15 years who were not treated before the study; group II: 15 patients treated with GH at start ages of between 5.2-14.8 years; group III: 17 patients treated with oxandrolone at start ages of between 5.3 and 15.2 years; group IV: 17 patients treated with estrogens and divided in different subgroups: IVa: seven patients treated with GH and estrogens at start ages of between 6.1 and 12.9 years; IVb: five patients treated with oxandrolone and estrogens at start ages of between 13.4 and 17.4 years, and IVc: five patients treated with oxandrolone, GH and estrogens at start ages of between 10.3 and 16.1 years. Bone mass was evaluated by a radiogrammetric method that measures the cortical thickness and bone diameter of three metacarpal bones with a magnifying glass. The results are expressed in SD according to Spanish longitudinal reference standards (Andrea Prader Center of Growth and Development) from 0.5 to 9 years of age and to Swiss standards from the age of 10 years onwards. Statistical significance was set at p < 0.05.

RESULTS

Group I (spontaneous development): cortical development was below the mean and was significantly diminished at the ages of 9, 13 and 14 years; bone diameter was decreased in relation to controls throughout the study period; group II (impact of GH treatment): cortical thickness showed a nonsignificant increase of 0.6 SD from baseline to years 3-4 of treatment and diameter increased by 0.5 SD from baseline to year 4 of treatment; group III (impact of oxandrolone): cortical thickness increased from -0.8 SD before treatment to 0.0 SD at years 2 and 3 of treatment; bone diameter increased from -1.5 SD at baseline to -1 SD at 3 years of treatment; group IV (impact of treatment with estrogens); IVa: cortical thickness and bone diameter increased; IVb: cortical thickness increased but bone diameter was unchanged; IVc: both cortical thickness and bone diameter increased.

CONCLUSIONS

The results of this study show that cortical thickness and bone diameter are decreased in untreated girls with Turner syndrome; cortical thickness was significantly decreased at the ages of 9, 13 and 14 years, while bone diameter was diminished at all ages, suggesting the presence of osteopenia in these patients. GH treatment produced a nonsignificant increase in cortical thickness and bone diameter. Oxandrolone treatment showed a positive effect on bone mass during the first few years of therapy. Because of the small number of patients, conclusions cannot be reached on the effectiveness of estrogens.

The impact of technical conditions of X-ray imaging on reproducibility and precision of digital computer-assisted X-ray radiogrammetry (DXR)

OBJECTIVE

To evaluate the reproducibility of imaging and analysis for bone mineral density (BMD) determination using digital computer-assisted X-ray radiogrammetry (DXR; Pronosco X-posure, version V.2, Sectra Pronosco, Denmark); to verify potential factors that influence BMD extrapolation such as tube voltage, film-focus distance (FFD), film quality and brand (Kodak T-MAT-Plus, Konika SRH, Agfa Scopix), imaging technology (conventional, digital), imaging system (Kodak, Agfa) and exposure level (mAs); and to clarify whether DXR analysis based on printouts of digital images is comparable to analysis of conventional images.

DESIGN AND PATIENTS

The hand of a cadaver was X-rayed using varied parameters: 4-8 mAs, 40-52 kV, 90-130 cm FFD. Radiographs under standardised conditions were performed 10 times using a conventional machine (Philips Super 80 CP) and the printouts of a digital system (Digital Diagnost Philips Optimus) for the analysis of reproducibility. One image was scanned and analysed 10 times additionally for imaging reproducibility.

RESULTS

Reliability error of the system for the imaging process using conventional radiographs-rays was 0.49% (standard conditions: 6 mAs, 40 kV, 1 m FFD), using printouts of digital images was 2.89% (4 mAs, 42 kV, 1 m FFD) and regarding the analysis process was 0.22%. BMD calculation is not affected by alterations in FFD (precision error 1.21%), mAs (0.83%) or film quality/brand (0.38%), but differs significantly depending on tube voltage (2.70%). The system was not able to analyse conventional images with tube voltages of 49/52 kV.

CONCLUSION

DXR technology is stable with most of the tested parameters. Normative data should exclusively be used for calculations using similar tube voltage or correction factors. All other parameters had no significant influence on the BMD calculation. Reproducibility is high. For technical reasons it is not recommended to use the printouts of digital images for BMD determination.

Potential clinical relevance of digital radiogrammetry for quantification of periarticular bone demineralization in patients suffering from rheumatoid arthritis depending on severity and compared with DXA

The aim of this study was to investigate a new bone densitometric technology based on digital radiogrammetry (DXR) with respect to its ability to measure severity-dependent variations of bone mineralization in patients with rheumatoid arthritis. One hundred six randomly selected patients suffering from verified rheumatoid arthritis underwent digitally performed plain radiographs of the non-dominant hand and measurements of dual-energy X-ray absorptiometry (DXA) regarding total femur and lumbar spine. Using DXR the radiographs were analyzed retrospectively for bone mineral density (BMD) calculation. The severity was classified using Larsen score and Steinbroker stage blinded by two radiologists. A third radiologist reviewed the incongruently scored cases. Mean values of calculated parameters changed as follows from Larsen 1 to Larsen 5: Bone mineral density (DXR-BMD) decreased from 0.55 to 0.44 g/cm2 (p=0.000), DXR-MCI decreased from 0.44 to 0.33 (p=0.001), DXA-BMD (total femur) decreased from 0.92 to 0.78 g/cm2 (p=0.090) and DXA-BMD (lumbar spine) decreased from 0.91 to 0.84 g/cm2 (p=0.595). Similar results were verified for the Steinbroker stage. The relative decrease of BMD measured by DXR between the highest and lowest score was 20% for Steinbroker stage and Larsen score (p<0.05). The relative decrease of BMD using DXA revealed not such a significant result. Similar results were verified for metacarpal index (estimated by DXR). Correlations between BMD determined by DXR and by DXA were all significant (R=0.45 for lumbar spine and R=0.59 for total femur). Consequently, less than 35% of the DXR-BMD value is explainable by corresponding DXA values. The DXR-based BMD calculation seems to be able to distinguish severity and progress of the disease in contrast to those of DXA at lumbar spine and total femur.

Semi-automated evaluation of the cortico-medullar index on radius radiographs: a study in prepubertal girls

The aim of the study was to validate a non-invasive method allowing a semi-automatic cortico-medullar index (CMI) computation from standard radiographs. Fifty-five radiographs of the non-dominant radius of prepubertal girls (aged 10.12+/-1.47 years) were scanned (100 microm scanning resolution) by the same observer. To detect the grey level peaks, we used the Deriche's recursive filter applied to the grey level gradients and we defined the cortical areas by thresholding (iterative contour detection). The CMI was calculated as cortical areas divided by the total bone area. The reproducibility was tested through the analysis of ten radiographs scanned twice, on 5, 10, 15, 20, 30 and 40 lines at each side of a reference line located at the distal third part of the radius. We used the root mean square coefficient of variation (RMS-CV) as verification. Dual-Energy X-ray (DXA) was used for densitometry measurements of the whole body, and non dominant radius (mid-, distal third and ultra distal). The result attaining the best reproducibility concerned the 15-line position (Mean CMI=0.58+/-0.005 with a 1.36% RMS-CV). CMI correlated significantly with Bone Mineral Density (BMD) (r=0.40, 0.33 and 0.50, P<0.01, respectively, at the whole body, mid- and third distal of the radius), Bone Mineral Content (BMC) (r=0.32, 0.36, 0.34 and 0.35, respectively, at the whole body (P=0.01), mid- (P=0.007), third distal (P=0.01) and ultra distal of the radius (P=0.01)) but not with BMD at the ultra distal of the radius (r=-0.01, P=0.9). This semi-automated new method has been easily implemented, reproducible, and therefore, could be useful tool for the bone CMI computation.

Normative values of bone parameters of children and adolescents using digital computer-assisted radiogrammetry (DXR)

PURPOSE

To verify whether estimation of bone mineral density (BMD) using digital X-ray radiogrammetry (DXR) is possible on children and to determine normative values of both such a DXR-BMD estimate and a corresponding metacarpal index (DXR-MCI) on.

PATIENTS AND METHODS

In retrospect, X-rays were selected of the hands of 200 healthy Caucasian children (120 boys and 80 girls, aged 4-18 yr). The involved children were selected among a larger group of children submitted to the surgical department of our institute for evaluation of a suspected fracture after an occurred trauma. All children with a verified fracture or a chronic bone-related disease, including bone age retardation or acceleration, were excluded from the study. Furthermore, only conventional X-rays with the same film and capture parameters were included. The images were scanned and analyzed using the Pronosco X-posure system V.2 (Sectra Pronosco, Denmark). DXR-BMD, DXR-MCI, and a porosity index (DXR-PI) were automatically calculated using the midshafts of the metacarpals II-IV. Mean values of DXR-BMD and DXR-MCI were calculated separately for girls and boys in 2-yr intervals.

RESULTS

In the present study the system has been demonstrated to be capable of calculating DXR-BMD from conventional X-rays of the hand from children down to approx 6 yr of age. This ability depended somewhat on the diameter and the length of the involved metacarpals. The success rate was higher for large bones than for small bones. The system succeeded in analyzing the images of 110 boys and 68 girls. Values of DXR-BMD were observed to increase with age from 0.40 g/cm2 to 0.62 g/cm2 in the male group and from 0.39 g/cm2 to 0.54 g/cm2 in the female group. Girls aged 11-12 yr had a higher DXR-BMD than did boys, corresponding to the earlier entry to puberty of girls. Standard deviations (SDs) reached values of up to 0.05 g/cm2. DXR-MCI increased with age from 0.36 to 0.47 for boys and from 0.34 to 0.49 for girls with a maximum SD of 0.06. The correlation between DXR-BMD and age was r=0.83 and r=0.84 for boys and girls, respectively. The corresponding correlations for DXR-MCI was lower, with observed correlations of r=0.63 (boys) and r=0.68 (girls), respectively, with p<0.01 in all cases. The DXR-PI did not reveal a significant correlation to age (r=-0.31 and r=0.04. respectively) and showed SDs marginally higher than the calculated mean values.

CONCLUSION

The newly available DXR-methodology seems to offer the ability to determine DXR-BMD and DXR-MCI in children starting with a bone age of 6. This possibility may be of special relevance for children suffering from chronic bone diseases that require repeated X-rays of the hand (e.g. to determine bone age). The acquired normative data suggest that the measurements are of clinical value owing to low age-dependent variability (SDs) relative to an observed high increase with age. The clinical value of the porosity index (DXR-PI) remains uncertain and is limited owing to a high inter-individual variability.

A normative reference database study for Pronosco X-posure System

Cortical width from radiographs has been used for more than 40 yr as a means of estimating bone strength. In the last 5-10 yr, increased availability of computers and the development of automated algorithms for image assessment have led to an increased interest in radiogrammetry. In this study, we examined a new radiogrammetry device, the Pronosco X-posure System, which estimates bone mineral density (BMD) from forearm/hand radiographs. We obtained hand and forearm radiographs and performed dual X-ray absorptiometry (DXA) at the wrist and hip on 832 women ages 20-79 at four clinical centers across the United States. We then used the X-posure System to estimate BMD (DXR-BMD). The goal of the study was to establish reference ranges for the method and to compare the measurement to DXA measurements of BMD at the wrist and hip. Using statistical models, we estimated that the peak value for DXR-BMD occurred at age 38 (mean = 0.598 g/cm2, standard deviation = 0.034 g/cm2). The correlation between DXR-BMD and DXA was 0.90 at the wrist and 0.61 at the hip. The relationship of DXR-BMD to reported history of fracture was of similar magnitude to that for DXA at the wrist and hip. The strong correlation of DXR-BMD from the X-posure System with DXA at the wrist from the Hologic machine suggests that the X-posure System may be an alternative to DXA at the wrist for the assessment of osteoporosis.

[Cortical bone mass and risk factors for osteoporosis among postmenopausal women in our environment]

OBJECTIVE

To evaluate the relevance of the so called risk factors for osteoporosis among women.

MATERIALS AND METHODS

A total of 150 consecutive postmenopausal women who had been enrolled in the gynecology outpatient clinics of the Health Areas affiliated to the Alcalá de Henares University Hospital. Bone mass of these women was calculated as index of metacarpal cortical area/total area (CA/TA) (mm2), measured by radiogrammetry.

RESULTS

With the ANOVA test, a late menarchial age and a shorter reproductive life induced a lower bone mass (p < 0.0005 and < 0.05, respectively); also, a history of bone fractures without previous relevant trauma (p < 0.05) was obtained. By correlational studies, there was a negative significance between CA/TA index and chronological age, menarchial age, menopausal age and number of fractures (r = -0.20 to -0.30; p < 0.05 to < 0.0001) and a positive significance with years of reproductive life (r = 0.17; p < 0.05). These values virtually remain unchanged when with partial correlation are weight adjusted, but with the multiple regression model, the CA/TA index is negatively significant only with menopause years (p < 0.005). Taking the average of the metacarpal CA/TA index as value, a sensitivity of 50% and an specificity of 78% were obtained to indicate fractures and a negative predictive value of 92%.

CONCLUSION

These results indicate the greater importance of menarchial age, of reproductive life years and therefore of menopausal years, as determinants of postmenopausal bone mass and show a very acceptable specificity of the CA/TA index as predictive for bone fracture.

Age-dependent cortical bone loss in women from 18th and early 19th century London

Age-dependent cortical bone loss was investigated in an earlier British population. The study sample comprised female skeletons from the 18th/19th century crypt at Christ Church, Spitalfields, London. Bone loss was monitored using metacarpal radiogrammetry. Age at death was known exactly from coffin plates. Results indicated that peak cortical thickness was less than in modern subjects. Continuing periosteal apposition was evident throughout adulthood, and the rate of increase in metacarpal diameter resembled that in modern subjects. Bone loss from the endosteal surface was evident from the fifth decade onwards, and this outstripped the rate of subperiosteal gain so that there was a net loss of cortical bone with age. Cortical bone loss occurred at a similar rate to that in modern subjects. In contrast to modern populations, there was no evidence that loss of cortical bone was associated with increased propensity to fracture. The present results, together with those previously published for a British medieval skeletal assemblage, suggest that patterns of cortical bone loss in women have remained unchanged over at least the last millennium in Britain. Given the great changes in lifestyle which have occurred during this period, this suggests that lifestyle factors may be rather less important than is sometimes asserted in influencing the severity of osteoporosis, at least as far as loss of cortical bone is concerned.

Second metacarpal midshaft geometry in an historic cemetery sample

Study of bone mass at the second metacarpal midshaft has contributed to our understanding of skeletal growth and aging within and between populations and has relied extensively on noninvasive techniques and in particular radiogrammetric data. This study reports age, sex, and side variation in size and shape data acquired from direct measurement of cross-sections obtained from a large (n = 356), homogeneous skeletal sample. Correlation analysis and three-way ANOVA of size-adjusted data confirm general impressions of patterned variation in this element: males have absolutely but not necessarily relatively larger bones than females; the right side is larger than the left, though a larger than expected proportion (approximately 25%) of left metacarpals exhibits greater values than the right; and bone mass but not strength (in males) declines with age. Contrary to the widely accepted assumption of circularity for this location, direct measurement of cross-sectional geometry confirms previous biplanar radiogrammetric conclusions regarding the noncircularity of the second metacarpal midshaft and identifies a significant difference between males and females, with the latter having a more cylindrical diaphysis. Deviation of the axes of maximum and minimum bending strength associated with noncircularity suggests a distribution of bone mass to resist bending moments perpendicular to the distal palmar arch, though this conclusion awaits more robust study of the functional anatomy of the metacarpal diaphysis.

Bias and agreement for radiogrammetric estimates of cortical bone geometry

RATIONALE AND OBJECTIVES

Radiogrammetry of the second metacarpal assumes a circular or elliptical model, which does not conform to reality. This study assesses the degree of bias and limits of agreement (error) resulting from deviations from these assumed models for estimates of bone mass and strength.

METHODS

Forty-six left metacarpals were radiographed in orthogonal posteroanterior and mediolateral views for calculation of algebraic estimations of area and bending moments of area. The bones were then sectioned at midshaft and digitized for determination of actual values of these properties. Bias was determined as the mean difference between methods, and error as +/-2 standard deviation.

RESULTS

Radiogrammetric methods significantly (P < 0.05) overestimate actual values for measures of cortical area and bending strength. Elliptical models are less biased and prone to smaller ranges of error than are uniplanar circular models.

CONCLUSIONS

Radiogrammetric estimation of metacarpal bone mass is subject to considerable method error arising from use of an overly simplistic circular model for its midshaft geometry.

Usefulness of panoramic radiography in the diagnosis of postmenopausal osteoporosis in women. Width and morphology of inferior cortex of the mandible

OBJECTIVES

To evaluate the usefulness of width and morphology of the inferior cortex of the mandible on panoramic radiographs in the diagnosis of postmenopausal osteoporosis.

METHODS

The width and morphology of the mandibular inferior cortex on panoramic radiographs were compared with trabecular bone mineral density (TBMD) of the 3rd lumbar vertebrae (L3) measured by dual energy quantitative computed tomography in 29 premenopausal and 95 postmenopausal women.

RESULTS

There was a significant negative correlation between the width (Kendall's tau = -0.36, p < 0.001) and morphology (Kendall's tau = -0.49, p < 0.001) of the mandibular inferior cortex and the L3 TBMD. Regression analysis showed that significant linear relationships were observed between the L3 TBMD and age (p < 0.001), cortical width (p < 0.05), morphology (p < 0.05), controlling body mass index, number of teeth present and menopausal status (R2 = 0.42).

CONCLUSION

Our results suggest that panoramic radiography could be reliable in screening for osteoporosis.

New evidence that serum beta(2)-microglobulin behaves as a biological marker of bone remodelling in women

Having observed that serum beta(2)-microglobulin concentration correlates with serum tartrate-resistant acid phosphatase (TRAP) concentration in postmenopausal osteoporosis, and that metacarpal endosteal diameter is dependent on bone resorption, we correlated the two biochemical parameters with the radiographic parameter to determine if beta(2)-microglobulin behaves like a biological marker of bone remodelling. In 105 women (mean age 68 +/- 4 years) consisting of 60 normal postmenopausal women and 55 osteoporotic postmenopausal women, there was a significant positive correlation between metacarpal endosteal diameter and these two biochemical values (r = 0.66 with beta(2)-microglobulin and r = 0.68 with TRAP in the osteoporotic postmenopausal women; r = 0.48 with beta(2)-microglobulin and r = 0.56 with TRAP in the normal postmenopausal women; P < 0.001 for all comparisons). All three measurements were significantly higher (P < 0.001) in the osteoporotic postmenopausal women than in the normal postmenopausal women. These findings show that serum beta(2)-microglobulin behaves like a biological marker of remodelling.

Bone mass in Parkinson's disease: a study with three methods

Recent reports suggest the presence of osteopenia in a high percentage of patients with Parkinson's disease (PD). These data contrast with previous reports of our group, perhaps due to the different methods used. We studied bone mass in 52 PD patients (28 males, 24 females) and in 80 age- and sex-matched controls (40 males, 40 females) who had no other disease that could affect bone mass. We measured the totally body bone mineral content (TBBMC) and the ultrasound bone velocity (UBV) of transmission in phalanx, and performed metacarpal radiogrammetry with computerized radiography (CCT). We also measured serum levels of total alkaline phosphatase and tartrate-resistant acid phosphatase, which were significantly increased in PD patients compared with controls (P < 0.0001). TBBMC was significantly lower in males (P < 0.05) and females (P < 0.05) with PD with respect to their controls. CCT did not differ significantly between the study groups. UBV was significantly lower in males with PD (P < 0.005), but similar in female PD and controls. These data suggest that the changes reported in bone mass in PD patients can depend on the sex and the study methods. We only found severe osteopenia in one male (3.6%) and five females (20.8%) with PD according to z-score. Only in women was no relationship found between TBBMC and severity of PD.

Behavior of bone mass measurements. Dual energy x-ray absorptiometry total body bone mineral content, ultrasound bone velocity, and computed metacarpal radiogrammetry, with age, gonadal status, and weight in healthy women

RATIONALE AND OBJECTIVES

Bone mass as measured by dual energy x-ray absorptiometry varies with body weight. The authors studied the behavior of bone mass measurements made by ultrasound bone velocity and metacarpal radiogrammetry in relation to body weight.

METHODS

Eighty healthy women were studied: 40 post-menopausal and 40 premenopausal (mean age 60 +/- 6 and 38 +/- 8 years, respectively). The authors performed in every subject the following studies: a radiograph of the nondominant hand for metacarpal cortical thickness, a study of the 2nd to 5th proximal phalanges for ultrasound bone velocity, and total bone mineral content by dual energy x-ray absorptiometry.

RESULTS

The measurements obtained with the three methods correlated significantly with each other (P < 0.0001). The only parameter related significantly with weight were total bone mineral content (P < 0.0001). In the premenopausal women, age did not correlate with any measurement. In the postmenopausal women, age correlated significantly with the three measured parameters (P < 0.0058 to P < 0.0001).

CONCLUSIONS

Weight did not influence ultrasound bone velocity and metacarpal cortical thickness measurements.

Computed radiographic absorptiometry and morphometry in the assessment of postmenopausal bone loss

The best method for the diagnosis of osteoporosis and assessment of fracture risk is currently considered to be bone densitometry. The most commonly used dual-energy X-ray absorptiometry (DXA) methods may sometimes not predict bone mass accurately in every skeletal site, are expensive and not widely available. The recent development of computed analysis of a plain radiograph of the hand might provide a practical, inexpensive and rapid method for evaluation of bone mineral status. In this study we evaluated 20 healthy premenopausal and 660 postmenopausal women. In 36 of these subjects a second evaluation was carried out after 2 years of therapy with calcium supplements. The internal and external diameters of the second metacarpal and the metacarpal and ultradistal radial bone density were evaluated using a technical device developed in our laboratory and marketed by NIM, Verona, Italy (Osteoradiometer). The radiographic images, captured by a video camera, were digitized and studied by computed analysis. In 150 subjects bone density at the level of the lumbar spine, femur, and ultradistal and proximal radius was also measured by DXA techniques. Both external (D) and internal (d) diameters increase significantly with age and years since menopause (YSM), whereas metacarpal index (D--d/D) and metacarpal and ultradistal radial bone density decrease significantly with age and YSM. The ratio between metacarpal bone mineral content and the cortical area (volumetric metacarpal bone density) did not change with age. Significant correlations were found between radiometric findings and DXA measurements. The best correlation coefficients were between bone density measured at the level of the ultradistal radius by DXA and radiographic absorptiometry. In the 2-year follow-up study, a 4.9% and 6.2% decline in radial metacarpal bone density respectively were observed, but the difference was statistically significant only for the latter. In conclusion, computed radiogrammetry is closely correlated with all DXA measurements and may be useful in screening of large populations, providing a simple, inexpensive and sufficiently precise method for evaluation of bone mineral status. Further studies are warranted for assessing the accuracy of radiogrammetry for longitudinal investigations and its capacity to predict fracture risk.

Effects of age, sex, and heredity on measures of bone mass in baboons (Papio hamadryas)

Bone mass and bone density were estimated in 219 pedigreed baboons (Papio hamadryas) by radiographic morphometry of the left second metacarpal. Compact bone width (total bone width--medullary canal diameter) and bone ratio (compact bone width/total bone width) decreased with increasing age squared in both sexes. The heritability of medullary canal diameter was 0.64 +/- 0.11, of compact bone width was 0.40 +/- 0.15 and of bone ratio was 0.67 +/- 0.13. The results indicate baboons are a useful model for studies of age, sex and genetic effects on bone mass.

Predicting vertebral deformity using bone densitometry at various skeletal sites and calcaneus ultrasound

We investigated the usefulness of bone density measurements from multiple skeletal sites and calcaneus ultrasound for evaluating the probability of vertebral deformation. Bone mineral density (BMD) was measured at the second metacarpal and middle phalanges using radiographic absorptiometry of hand radiographs, and at the lumbar spine using dual-energy x-ray absorptiometry. Distal radius and proximal radius were measured using single-energy x-ray absorptiometry (SXA), expressed as bone mineral content (BMC, grams per centimeter), and as BMD (grams per square centimeter). The calcaneus was measured using both SXA (BMD) and broadband ultrasound attenuation (BUA). Among the women in this study (mean age 74, SD = 5), 84 women developed new vertebral deformations (57 cases with one and 27 cases with two or more deformations), which were identified on serial radiographs during an average of 9 years prior to the measurements of bone density. Logistic regression analysis was used to calculate odds ratios for risk of deformation corresponding to a 1-SD difference in density or ultrasound, adjusted for age. All bone measurements were significantly associated with vertebral deformation, with odds ratios (95% confidence intervals) ranging from 1.40 (1.10, 1.78) for proximal radius BMD to 1.88 (1.45, 2.44) for calcaneus BMD measurements. Measurements of calcaneal BUA, calcaneal BMD, and hand BMD generally remained significant when included simultaneously with another measurement in the same model, suggesting that spine or radius BMD may not provide much additional information about risk of deformation. It appears that all of the measurements of bone density and ultrasound provide useful information regarding the probability of deformation. These findings await confirmation in a prospective study.

Total and regional bone mineral content and fracture rate in postmenopausal osteoporosis treated with salmon calcitonin: a prospective study

Seventy-two postmenopausal osteoporotic women having more than one nontraumatic vertebral crush fracture were studied. Thirty-six of them, aged 68.8 +/- 1.2 years (18 +/- 4 YSM-years since menopause), were treated with 100 IU/day of salmon calcitonin i.m. plus 500 mg of elemental calcium for 10 days each month. The remaining 36 patients, aged 69.6 +/- 1.4 years (19 +/- 3 YSM), were given only 500 mg of elemental calcium for 10 days each month. All patients underwent clinical and analytical evaluation every 3 months. Radiological evaluation, assessment of vertebral deformities, and metacarpal radiogrammetry were done every 6 months. Densitometric measurements of total and regional bone mass were made every 12 months. At 24 months, the calcitonin group showed a 60% reduction in the number of new fractures and the group receiving only calcium had a 45% increase (P < 0.001). The incidence of vertebral fractures was 0.07 per patient-year in the group treated with calcitonin and 0.45 per patient-year in the group treated with calcium (P < 0.001). At 2 years, the calcitonin group showed a 12% increase in cortical bone mass on metacarpal radiogrammetry, a 16% increase in the axial skeleton on trunk densitometry, a 3.5% increase in total body bone mineral content, a 30.7% increase in pelvic bone mineral content, and a 6.2% increase in arm bone mineral content (all P < 0.001). In the group treated with calcium alone there was a loss of bone mass in every region. These findings suggest that salmon calcitonin is effective in the treatment of osteoporosis and show that it acts on cortical and trabecular bone.

Assessment of bone density in the distal radius with computer assisted X-ray densitometry (CXD)

A modified and improved radiographic absorptiometry of the distal radius which enables on-site analysis, called computer assisted X-ray densitometry (CXD), was evaluated from the viewpoint of quality assessment. Its precision and the correlation with dual energy X-ray absorptiometry (DXA) was evaluated in 12 volunteers (mean age 44.7 years). The profile of CXD-measured radial bone mineral density (RBMD) from 142 subjects (75 premenopausal and 67 postmenopausal women, mean ages 44.9 and 50.6 years, respectively) were compared with previous data by other methodologies of bone mineral analysis. The intra-assay coefficient of variation (CV) was 0.617%, the inter-assay CV was 2.064%, and the inter-observer CV was 0.673%. The correlation between CXD-measured RBMD and DXA-measured RBMD was of statistical significance (r2 = 0.733, P < 0.01). The correlation of CXD-measured RBMD with age, height or weight corresponded well with previous reports. CXD-measured RBMD and DXA-measured vertebral bone mineral density (VBMD) also had a significant positive correlation, but their correlation was not so close (r2 = 0.149, P < 0.01). The discriminative ability of osteoporosis by CXD was of acceptable level (odd's ratio = 5.72, P < 0.05), when assessed by comparison with bone dystrophy score (BDS) on the plain vertebral radiogram. Although some problems remain in technical standardization, CXD could be an easy, inexpensive, and widely applicable alternative of non-weight bearing cancellous bone densitometry.

Metacarpal bone mass in normal and osteoporotic Japanese women using computed X-ray densitometry

The metacarpal bone mineral density (BMD) and metacarpal index (MCI) of the second metacarpal bone were measured by computed X-ray densitometry (CXD) (Teijin Ltd., Tokyo), which we have established with the development of microdensitometry of radiographs. In this study, we evaluated the basic attributes of this CXD method and determined the age-related changes in both metacarpal measurements in normal Japanese women. The precision in vivo was measured in eight subjects. The precision errors [coefficient of variation (CV)] were 0.2-1.2% CV for metacarpal BMD and 0.4-2.0% CV for MCI, respectively. We have obtained low precision error and more rapid analysis, within 3 minutes respectively, compared with the previous methods. Age-related changes in the metacarpal measurements were evaluated in 1438 normal women. Both measurements showed the most significant decrease in the sixth decade of life. The rate of decrease in the sixth decade was 1.6%/year for metacarpal BMD and 1.5%/year for MCI. On comparison between metacarpal BMD by CXD and spine BMD using dual energy X-ray absorptiometry (DXA) in 248 normal women with and without menstruation, the two measurements were found to be similarly decreased in the subjects within 5 years after menopause. There was also no significant difference in the Z-score between metacarpal BMD and spine BMD within 5 years after menopause. These results indicate that early postmenopausal bone loss occurs not only in the spine but also in the metacarpal bone.(ABSTRACT TRUNCATED AT 250 WORDS)

Automated computerized radiogrammetry of the second metacarpal and its correlation with absorptiometry of the forearm and spine

The value of a new computerized radiogrammetric method of assessment of the second metacarpal has been evaluated, and its results have been compared with those of single (SPA) and dual photon absorptiometry measurements (forearm and spine) in 74 and 79 postmenopausal women, respectively. Standard hand X-rays were digitized by a video-camera connected to a microcomputer. The combined cortical thickness (CCT) was automatically calculated in a zone of 10 mm around the midpart of the second metacarpal. The intra- and interobserver coefficients of variation were close to 1%. The correlation between CCT and SPA of the proximal and midforearm (with a significant amount of cortical bone) was satisfactory (r = 0.62 and 0.50, respectively; P < 0.001). The correlation between CCT and osteodensitometry of sites comprising more trabecular bone were not so good (0.50 for lumbar and 0.44 for distal forearm bone mineral density, respectively), but still significant (P < 0.001). Radiogrammetry proved unaffected by a change of X-ray apparatus, as measurements of 48 metacarpals radiographed by two different kinds of X-ray apparatus were not significantly different. Radiogrammetry is by no means the best method to evaluate bone mass. Its automation did not improve the correlation with osteodensitometric values. Radiogrammetry is still of interest in mass screening, particularly when other more expensive techniques such as osteodensitometric methods of bone mass measurement are not readily available. Its automation makes it simpler, faster, and more precise, rendering its use easier on a larger scale.

Influence of weight and seasonal changes on radiogrammetry and bone densitometry

We studied the behavior of radiogrammetric and densitometric measurements in relation to season and body weight in a group of 30 healthy premenopausal women. Measurements were made at 6-month intervals, in summer/fall when bone density increases and in winter/spring when bone density declines. Total body bone mineral content (TBBMC) and regional bone mineral content (RBMC) were measured using dual-energy X-ray absorptiometry (DXA). Metacarpal radiogrammetry was carried out with computed radiography. Weight and body mass index increased significantly in winter (P < 0.05) and total body and RBMC decreased (P < 0.001). The opposite occurred in summer: weight and body mass index decreased significantly (P < 0.05) and total body and regional bone mineral content increased (P < 0.001). Differences in TBBMC persisted when the measurement was corrected for weight (TBBMC/W) (P < 0.001), but not for metacarpal cortical thickness corrected for weight. In the first measurement made there were significant relations between weight and both TBBMC (P < 0.001) and metacarpal cortical thickness (P < 0.005). The relation between weight and TBBMC remained significant in later measurements, but the relation between weight and metacarpal cortical thickness ceased to be significant in the second and fourth measurements. Our results show that there is an important seasonal variation in bone mass and that DXA is more sensitive than radiogrammetry in registering these changes.

Metacarpal cortical thickness by computed radiography in osteoporosis

Computed radiography was used to make radiogrammetric measurements of the second metacarpal in 240 women, 180 considered normal and 60 osteoporotic. These measurements had a coefficient of variation for the external diameter of 0.74% in normal women and 0.75% in osteoporotic women, and for the internal diameter of 2.4% and 2.03%, respectively. The group of women with osteoporosis was divided according to external diameter and internal diameter into a group with osteoporosis due to increased bone resorption (61.1%, normal external diameter and increased internal diameter), and osteoporosis due to deficient bone formation (26.1%, decreased external diameter and normal internal diameter). In the remaining subjects (12.8%), osteoporosis was attributed to both mechanisms. There was a significant linear regression between internal diameter and tartrate-resistant acid phosphatase concentration (p < 0.0001) in the group of increased bone resorption, which was absent (p = ns) in the group with deficient bone mass formation. No changes were observed in the size of the two groups. The low coefficient of variation of radiogrammetric measurements with computed radiography validate it as an accurate technique for bone mass studies. Moreover, it has the additional advantage of permitting determination of the proportion of women with osteoporosis due to increased bone resorption and/or deficient bone mass formation.