Femoral trabecular-pattern index for evaluation of spinal osteoporosis

Enhancement of Hip X-ray with Convolutional Autoencoder for Increasing Prediction Accuracy of Bone Mineral Density

It is very important to keep track of decreases in the bone mineral density (BMD) of elderly people since it can be correlated with the risk of incidence of major osteoporotic fractures leading to fatal injuries. Even though dual-energy X-ray absorptiometry (DXA) is the one of the most precise measuring techniques used to quantify BMD, most patients have restricted access to this machine due to high cost of DXA equipment, which is also rarely distributed to local clinics. Meanwhile, the conventional X-rays, which are commonly used for visualizing conditions and injuries due to their low cost, combine the absorption of both soft and bone tissues, consequently limiting its ability to measure BMD. Therefore, we have proposed a specialized automated smart system to quantitatively predict BMD based on a conventional X-ray image only by reducing the soft tissue effect supported by the implementation of a convolutional autoencoder, which is trained using proposed synthesized data to generate grayscale values of bone tissue alone. From the enhanced image, multiple features are calculated from the hip X-ray to predict the BMD values. The performance of the proposed method has been validated through comparison with the DXA value, which shows high consistency with correlation coefficient of 0.81 and mean absolute error of 0.069 g/cm2.

A novel approach for evaluating bone mineral density of hips based on Sobel gradient-based map of radiographs utilizing convolutional neural network

Osteoporosis, which is a common disorder associated with low bone mineral density (BMD), is one of the primary reasons for hip fracture. It not only limits mobility, but also makes the patient suffer from pain. Unlike traditional methods, which require both expensive equipment and long scanning times, this study aims to develop a novel technique employing a convolutional neural network (CNN) directly on radiographs of the hips to evaluate BMD. To construct the dataset, X-ray photographs of lower limbs and dual-energy X-ray absorptiometry (DXA) results of the hips of patients were collected. The core of this research is a deep learning-based model that was trained using the pre-processed X-rays images of 510 hips as the input data and the BMD values obtained from DXA as the standard reference. To improve performance quality, the radiographs of the hips were processed with a Sobel algorithm to extract the gradient magnitude maps, and an ensemble artificial neural network which analyses the outputs of CNN models corresponding to three Singh sites and biological parameters was utilized. The superior performance of the proposed method was confirmed by the high correlation coefficient of 0.8075 (p<0.0001) of the BMD measured by DXA in a total of 150 testing cases, with only 0.12 s required for applying the computing configuration to a single X-ray image.

Quantitative imaging techniques for the assessment of osteoporosis and sarcopenia

Bone and muscle are two deeply interconnected organs and a strong relationship between them exists in their development and maintenance. The peak of both bone and muscle mass is achieved in early adulthood, followed by a progressive decline after the age of 40. The increase in life expectancy in developed countries resulted in an increase of degenerative diseases affecting the musculoskeletal system. Osteoporosis and sarcopenia represent a major cause of morbidity and mortality in the elderly population and are associated with a significant increase in healthcare costs. Several imaging techniques are currently available for the non-invasive investigation of bone and muscle mass and quality. Conventional radiology, dual energy X-ray absorptiometry (DXA), computed tomography (CT), magnetic resonance imaging (MRI) and ultrasound often play a complementary role in the study of osteoporosis and sarcopenia, depicting different aspects of the same pathology. This paper presents the different imaging modalities currently used for the investigation of bone and muscle mass and quality in osteoporosis and sarcopenia with special emphasis on the clinical applications and limitations of each technique and with the intent to provide interesting insights into recent advances in the field of conventional imaging, novel high-resolution techniques and fracture risk.

Imaging Findings and Evaluation of Metabolic Bone Disease

Bone is a dynamic organ of the endoskeleton, playing an important role in structural integrity, mineral reservoirs, blood production, coagulation, and immunity. Metabolic bone disease encompasses a broad spectrum of inherited and acquired disorders that disrupt the normal homeostasis of bone formation and resorption. For patients affected by these processes, radiologic imaging plays a central role in diagnosis, monitoring treatment, and risk stratification. Radiologists should be familiar with the diseases, intimately aware of the imaging findings, and possessive of multimodality expertise to wisely guide the best practice of medicine. The purpose of this paper is to review the imaging features and characteristics of the most common types of metabolic bone disease with highlights of clinically relevant information so that readers can better generate appropriate differential diagnoses and recommendations. For this review, a thorough literature search for the most up-to-date information was performed on several key types of metabolic bone disease: osteoporosis, osteomalacia, rickets, scurvy, renal osteodystrophy, hyperparathyroidism, Paget’s disease, osteogenesis imperfecta, acromegaly, and osteopetrosis. Although they all affect the bone, these diseases have both shared characteristic features that can be discerned through imaging.

The relationships between femoral cortex geometry and tissue mechanical properties

Bone tissue and geometry are constantly modified through modeling and remodeling at the periosteal, endosteal and intracortical envelopes. Results from several studies indicate that femoral bone geometry is a predictor of whole bone strength (e.g. femoral neck strength), however, it is not known whether there is a relationship between bone structural and material properties. Bone geometry can be determined from parameters based on plane X-ray radiogrammetry which are used to evaluate femoral bone quality for implant success. If there is a relationship between these parameters and tissue mechanical properties, this would have implications in the interpretation of such parameters for assessment of fracture risk and in further understanding of bone biology. Following measurement of radiogrammetric parameters from antero-posterior and medio-lateral X-rays (cortical thickness, bone diameter, bone area, moment of inertia, cortical index, Singh index), human femurs were machined into standard test specimens for assessment of tensile fracture toughness (GIc) of the tissue. Results indicated that tensile fracture toughness generally increased with increasing bone size. We also found that fracture toughness of the tissue was significantly related to radiogrammetric indices and that some of these indices explained a greater variability in toughness than porosity, age or gender.

Integrated imaging approach to osteoporosis: state-of-the-art review and update

Osteoporosis is the most common of all metabolic bone disorders. It is characterized by low bone mass and microarchitectural deterioration of bone tissue, with a consequent increase in bone fragility and susceptibility to fractures. Because of the increasing aging of the world population, the number of persons affected by osteoporosis is also increasing. Complications related to osteoporosis can create social and economic burdens. For these reasons, the early diagnosis of osteoporosis is crucial. Conventional radiography allows qualitative and semiquantitative evaluation of osteoporosis, whereas other imaging techniques allow quantification of bone loss (eg, dual-energy x-ray absorptiometry and quantitative computed tomography [CT]), assessment for the presence of fractures (morphometry), and the study of bone properties (ultrasonography). In recent years, new imaging modalities such as micro-CT and high-resolution magnetic resonance imaging have been developed in an attempt to help diagnose osteoporosis in its early stages, thereby reducing social and economic costs and preventing patient suffering. The correct diagnosis of osteoporosis results in better management in terms of prevention and adequate pharmacologic or surgical treatment.

Radiology of osteoporosis

Bone densitometric studies have shown that osteoporosis is a result of prolonged, slow bone loss and that the pattern of loss is different for trabecular and cortical bone. Structurally-insufficient osteoporotic bone is predisposed to fractures. Among the clinically manifest osteoporotic fractures, distal radius leads the list, followed by hip, spine, and proximal humerus. This article examines the use of conventional radiography as well as other imaging-based modalities for the evaluation of osteoporosis and associated fractures in the axial and appendicular skeleton.

A displaced stress fracture of the femoral neck in an adolescent female distance runner with female athlete triad: A case report

This report presents a case of a displaced stress fracture of the femoral neck in an adolescent female distance runner with amenorrhea. Both reduction and internal fixation were performed early after the injury. At 24 months postoperatively, magnetic resonance imaging and bone scintigraphy showed no positive signs of femoral head necrosis and bone union was confirmed on plain X-ray. A medical examination for the presence of the signs of the female athlete triad by checking weight, calorie intake and menstrual cycles is most important to prevent such stress fractures. Athletes as well as their coaches or parents therefore need to understand female athlete triad.

Low reoperation rate with the Medoff sliding plate: 1 technical failure in 63 trochanteric hip fractures

The Medoff sliding plate was designed to treat unstable intertrochanteric and subtrochanteric fractures. This plate has a dual sliding capability along both the femoral shaft and neck in order to improve bone coaptation, interfragment compression and hence load-sharing between bone and implant in hip fractures. In a retrospective study of 63 patients (mean age 82 (51-98) years) with intertrochanteric (n 44) and high subtrochanteric fractures (n 19), we assessed the results with the Medoff sliding plate. All patients, except 1 lost to follow-up, were examined clinically and radiographically. 14 patients died within 1 year, and in the other, the mean follow-up was 15 (6-30) months. 1 technical failure occurred, leading to a single reoperation. The low technical failure rate suggests that the Medoff sliding plate with combined compression modus is suitable for treating intertrochanteric and high subtrochanteric fractures.

Imaging of metabolic bone diseases

Osteoporosis is a serious public health problem. The incidence of osteoporotic fractures increases with age. As life expectancy increases, social costs associated with osteoporotic fractures will multiply exponentially. The early diagnosis of osteoporosis, thanks to evermore precise devices, becomes, therefore, fundamental to prevent complications of disease and unnecessary suffering.

Osteoporosis

Effective therapies are available for the patient who has arthritic osteoporosis. The approach is critical to ensure an optimal quality of life in these individuals who suffer with a disease that is clearly treatable.

Osteoporosis

Bone is a complex organ which contains an organic matrix which serves as scaffolding, includes mineral as calcium distributed in a pattern providing structure and serves as an ion reservoir for the body. Throughout life it dynamically changes in response to changes in activity, body mass, and weight bearing. It is important to define patients at risk for bone loss, since accrued bone loss leading to osteoporosis in the older population of both men and women is unacceptable. There are many different therapies including biphosphonates which can decrease loss of bone and decrease fracture risk in patients who already have had sustained a fracture. Newer therapies such as parathyroid hormone may improve the fracture risk even more than biphosphonates over a shorter period of time.

Femoral neck trabecular patterns predict osteoporotic fractures

In this paper we show that texture analysis of femoral neck trabecular patterns can be used to predict osteoporotic fractures. The study is based on a sample of 123 women aged 44-66 years with and without fractures. We analyzed trabecular patterns using the Co-occurrence Matrix texture analysis algorithm and compared the predictive utility of the textural data with densitometry. Logistic regression was used to estimate the predictive utility, exp(B), of clinical and textural data per standard deviation. Reproducibility was also demonstrated using paired films at 1-year intervals (CoV=4.5%). Bone mass estimated by DEXA measurements of the spine and hip were the most predictive of fractures giving a two-fold increase in fractures per s.d. bone mass loss (95% CI: 1.2-3.1, p<0.005). Age was also highly predictive with fracture risk increasing by 1.07-fold per year (95% CI: 1.01-1.14, p<0.02). Trabecular texture was found to give a lower, but significant, prediction of fracture of 1.5-fold per s.d. trabecular pattern loss (95% CI: 0.96-2.31, p<0.05). Combining age, weight, and trabecular texture increased the fracture prediction to 1.78-fold per s.d. (95% CI: 1.19-2.67). Combining trabecular texture with densitometry increased the predictive ability to 2.06-fold per s.d. (95% CI: 1.32-3.22) and combined with age and weight as well increased exp(B) to 2.1-fold per s.d. (95% CI: 1.32-3.35). This shows that osteoporotic trabecular texture changes can be "measured." Moreover, the combination of age, weight, and trabecular texture is more predictive than either alone. We propose therefore that this trabecular texture analysis is both reproducible and clinically meaningful. The application of such methods could be used to improve the estimation of fracture risk in conjunction with other clinical data, or where densitometry data cannot be obtained (e.g., in retrospective studies).

Quantitative assessment of the clavicle radiostructure as a tool for estimation of the osteopathic effect of breast cancer chemotherapy

Radiological structure (trabeculation) of the clavicle was quantitatively evaluated using the chest X-ray images obtained in 36 pre-menopausal women subjected to CMF (cyclophosphamide, methotrexate, fluorouracil) chemotherapy. For comparison, the values of the quantitative radiostructural indices were estimated from the X-ray images obtained in 65 age-matched pre-menopausal healthy women and 19 post-menopausal women with clinically confirmed osteoporosis. For the analyses, the high-quality routine chest P-A films were used in which the central segment of the clavicle was well visualised. Evaluation of the skeletal radiostructure was carried out using the original software developed by K.W. Zieliński which, in addition to standardising the quality of the image, calculated the structural density as well as the arrangement and mean thickness of the trabeculae. The results demonstrate in a reproducible way that structural density and mean thickness of the clavicular trabeculae were significantly (p < 0.01) lower in pre-menopausal, CMF-treated and post-menopausal, osteoporotic patients than in healthy, control women. Likewise, the relative radiological density of the clavicle was reduced in the former two groups of women as compared to their control counterparts and the difference approached statistical significance. When the X-ray films were compared in each breast cancer patient before and after the chemotherapy the values of all the three parameters were decreased in up to 86% of the treated patients. Overall, the obtained results demonstrate the significant osteopathic side effect of the CMF chemotherapy in pre-menopausal breast cancer patients.

Femoral neck fractures

Femoral neck fractures in the geriatric patient continue to represent a therapeutic challenge. Despite advances in surgical techniques and medical care, the risk of nonunion and osteonecrosis after fixation have not changed appreciably in the last 50 years. Considerable debate continues to occur with respect to the relative merits of internal fixation versus arthroplasty. The relative benefits and complications of unipolar and bipolar hemiarthroplasty, as well as total hip replacement, continue to be poorly understood. The next decade will bring advances in the prevention and treatment of osteoporosis that may finally decrease the incidence of these fractures. Advances in the use of bone graft substitutes may finally improve the outcome of internal fixation.

Computerized tomography of proximal femoral trabecular patterns

A comprehensive imaging and pathologic investigation utilizing patients and cadaver material was performed in order to identify the normal trabecular pattern of the proximal femur and to assess alterations in this pattern in various disorders. Patients and specimens were studied with computed tomography (CT), including three-dimensional CT image reconstruction in selected cases and plain film radiography. The CT imaging of the proximal femur provides insight into the dynamic state of bone in this region. Despite limited resolution, three-dimensional CT image reconstruction is capable of portraying the concentration and orientation of major trabeculae in the proximal femur. Increased trabecular spacing occurs in osteoporosis and is well depicted by CT. Proliferation and thickening of the most superior subchondral primary compressive trabeculae is an early sign of osteoarthritis. In the region of the calcar femorale, crossing trabeculae, similar to the appearance of an enchondroma or bone infarct, have been described in osteoporosis and osteoarthritis and probably represent unmasking of normally present reinforcing trabeculae. In ischemic necrosis, CT should be considered a useful modality for detection of early or mild alterations and may be valuable in treatment planning.

Closed pelvic fractures: characteristics and outcomes in older patients admitted to medical and geriatric wards

OBJECTIVE

To investigate the characteristics and outcomes of older patients with pelvic fracture admitted to medical and geriatric wards.

METHODS

All patients admitted to medical and geriatric wards with a pelvic fracture over a four year period were identified using the hospital clinical coding database. Data were collected from casenotes, hospital and Family Health Services Authority databases. Where available, pelvic radiographs were graded according to the Singh index.

RESULTS

The casenotes of 148 patients (126 women) were studied; 83% (n=123) of patients suffered a pelvic fracture in low energy trauma. Mean (SD) length of hospital stay was 21.3 (17.6) days. Single breaks of the pubic rami accounted for 47.2% (n=68) of all fractures. Inpatient mortality was 7.6% and at one year was 27%. There was a marked adverse effect on the mobility of survivors with all patients using at least a walking stick at discharge and 51.1% (n=70) needing assistance for mobility. Although 70.9% (n=83) of patients admitted from home (or warden aided accommodation) were able to return there, 84.3% (n=70) of them required extra community support. Rates of institutionalisation rose from 20.9% (n=31) at admission to 35.8% (49/137) of survivors at discharge. Altogether 93% (n=107) of 115 patients, in whom adequate quality pelvic radiographs were available, were assigned a Singh index grade of 4 or less indicating the presence of osteoporosis.

CONCLUSIONS

Pelvic fractures are often the result of low energy trauma. They are associated with appreciable inpatient and considerable one year mortality. They also have marked negative effects on mobility in the short term. They result in increased levels of dependency in terms of higher levels of community support and rates of institutionalisation. On the evidence of Singh index grading, pelvic fractures are associated with low bone density.

Clinical epidemiology and osteoporosis. Measures and their interpretation

Identifying patients with a high risk of fracture and monitoring a patient's therapeutic response are important. Current methods to evaluate the risk of fracture include the measurement of bone mineral density as well as other risk factors, including those associated with the risk of falling. Several considerations are important in defining the risk for fracture. There is currently no level of bone mineral density at which the risk of fracture is zero, that is, some high-risk women will not have a fracture and some low-risk women will. The monitoring of high-risk individuals for subtle changes in their bone status is not economically feasible at this time. Given the precision of current measurement technology, it is more reasonable to expect to monitor individuals on a 3- to 5-year basis rather than every 6 months to 1 year. There is no single optimal site at which measurement is highly precise and predictive of bone mineral density measurement at other skeletal locations. Currently, measurement of the femoral neck seems to have the most universal applicability. Measurement of bone turnover markers remains more effective as a research tool and is less effective as a method to diagnose or monitor the bone status of individual patients.

Application of computer texture analysis to the Singh Index

The Singh Index, which describes trabecular patterns in the proximal femur, has been used as a predictor for hip fractures and as an indicator of osteopenia. Evidence suggests that its contribution to the assessment of hip fracture risk is in its description of the structural properties of the femur. However, subjectivity in its determination may limit its practical value. In this study, we have used computer texture analysis to characterize the textural changes in trabecular bone which occur in osteoporosis. Texture analysis of the proximal femur was used to rank radiographs of 25 cadaver femora by Singh grading. These rankings were compared with those performed by two experienced radiologists. The computer method performed better than the least consistent individual radiologist, but not as well as the two radiologists in combination. The method required no radiologist's time after the system had been 'trained' from a set of example radiographs. The method has potential for use in large studies in which speed and consistency of measurement are important.

Osteonecrosis of the femoral head in patients with inflammatory arthritis or asthma receiving corticosteroid therapy

The utilization of corticosteroids in the management of acute and chronic inflammatory processes, such as asthma or inflammatory arthritis, has been implicated in the adverse effects of multiple organ systems. One potential area of these negative consequences in the use of corticosteroids is the development of osteonecrosis of the femoral head. A direct time/dosage relationship for treatment with corticosteroids of patients with an established diagnosis of asthma or inflammatory arthritis and femoral osteonecrosis is unknown. A prospective study was undertaken to evaluate the use of corticosteroids and the incidence of osteonecrosis of the femoral head and potentially establish a time/dosage relationship in this patient population. No direct relationship between corticosteroid dosage and the development of femoral head osteonecrosis in 1420 hip-years was demonstrated at 10-year follow up.

Bone mineral density in Chinese elderly women with hip fracture

In order to examine the status of osteoporosis of the patients with hip fracture, we assessed the bone mineral density (BMD) of the contralateral hip of 81 elderly females with hip fracture and compared those with 77 normal Chinese women. The age of fracture subjects was 73.5 +/- 6.6 years (mean +/- SD), and 69.2 +/- 6.9 years for the controls. All of these fractures were caused by minor trauma, such as falls from a standing position or slipping to the ground. The Norland 2600 dual-photon absorptiometer (DPA) was used to evaluate the BMD in the femoral neck, trochanter, and Ward's triangle areas. The BMD for the fracture subjects was significantly lower than those of the controls. By linear regression, the probability of fracture increased exponentially with age and low BMD. The mean BMD for femoral neck of the fracture subjects versus controls was 0.556 versus 0.624 g/cm2; for trochanter: 0.505 versus 0.566 g/cm2; for Ward's triangle: 0.432 versus 0.485 g/cm2. Both negative predictive value (NPV) and positive predictive value (PPV) were acceptable at the prevalence of hip fracture of 5% or 20% and at a cutoff point of 0.65 g/cm2. These data revealed that the degree of relative osteoporosis in the patients with hip fractures was more severe than that of controls.

Prevalence of metacarpal osteopenia in young rheumatoid arthritis patients

The aim of this study was to assess the prevalence of and diagnostic role of metacarpal osteopenia in rheumatoid arthritis (RA) and to evaluate its detectability using receiver operating characteristic (ROC) analysis. Metacarpal bone mineral density was measured in 98 patients with classical RA using a computer-assisted measure of 6 metacarpal diameters (radiogrammetry) in patients aged less than 50 years. Sensitivity and specificity of the technique in discriminating the RA patients from 85 normal controls and osteopenic RA subjects from their normopenic counterparts, was determined by standard statistical techniques. Clinical, laboratory and radiological variables were compared in their ability to explain the variance of metacarpal bone density. The prevalence of metacarpal osteopenia in RA was 55%. Prolonged disease and reduced function significantly differentiated osteopenic from non-osteopenic RA patients. Discriminant analysis of RA and control groups showed that measurement of 6 metacarpals was more accurate than the 2nd metacarpal measurement alone in predicting the RA patients. The sum of 6 metacarpal combined cortical width (CCW) had a sensitivity of 61% and specificity of 68% in discriminating the RA patients from the controls. Receiver operating characteristics curves showed, not surprisingly, that objective measurement of bone diameters was superior to clinical or laboratory measures of disease activity in correctly classifying a randomly chosen RA patient as osteopenic or not. Metacarpal osteopenia is common in RA and it may be a useful measure of the disease in young patients.

Better discrimination of hip fracture using bone density, geometry and architecture

Bone density predicts the risk of hip fracture. Because hip strength is determined by bone geometry and architecture as well as density, we tested which variables in geometry and architecture were independent discriminators of hip fracture and, if combined with density, improved the discrimination of fracture from non-fracture over bone density alone. The design was a case-control study. The subjects were Caucasian women over the age of 60 years who had sustained a hip fracture after the age of 58 years (n = 22), and controls matched for age and weight (n = 43) and unmatched controls (n = 317) with no history of hip fracture. Variables in density, geometry and architecture were obtained from dual-energy X-ray absorptiometry images and from radiographs of the upper end of the femur. In a univariate model, of the measures of bone mass, the best discriminator of hip fracture was bone mineral density of the neck of femur; of the geometric measurements, it was hip axis length; and of the measurements of bone architecture, it was Singh grade. In a multivariate model, these three variables were shown to be independent discriminators of hip fracture. When hip axis length was combined with bone mineral density, there was significant improvement in discrimination of hip fracture (p = 0.014), and when Singh grade was combined with hip axis length and bone mineral density there was a further significant improvement (p = 0.002).(ABSTRACT TRUNCATED AT 250 WORDS)

A population study of the screening potential of assessment of trabecular pattern of the femoral neck (Singh index): the Chingford Study

The trabecular pattern of the femoral neck (Singh index) has been used as a measure of osteopenia and fracture risk but the value of this method is controversial. This study assessed the usefulness of the Singh index (SI) by using dual energy X-ray absorptiometry (DXA) as the "gold standard". 659 Caucasian women (45-70 years) from an age-sex register of a general practice had their femoral neck and lumbar spine bone densities measured by DXA and had antero-posterior hip X-rays performed which were then categorized into six osteopenia grades using the SI method. The intraobserver and interobserver reproducibility of this method was good (kappa = 0.64 and 0.61, respectively). The SI grades correlated significantly with body mass index (r = 0.35) and age (r = 0.17) (p < 0.001). The mean femoral neck and lumbar spine bone densities were significantly higher with increasing SI grade even after adjustment for age and body mass index (p < 0.001). The proportion of subjects below the fracture threshold (2 SD below mean peak bone mass) decreased with increasing SI grade, ranging from 100% in SI grade 2 to 16.8% in SI grade 6. There was, however, wide overlap of bone densities between the grades. Using the criteria "osteoporosis < or = SI grade 4", the sensitivity and specificity of the SI method diagnosing low bone mass was 35.1% and 90.0%, respectively. These data suggest that the SI is a reproducible tool which may detect differences in bone mass between populations or subgroups within populations, although caution should be used in classifying individual patients because of the wide variation in bone density. The method has a low sensitivity but a relatively high specificity in diagnosing low bone mass.

Prediction of hip fractures from pelvic radiographs: the study of osteoporotic fractures. The Study of Osteoporotic Fractures Research Group

To determine whether simple measurements made on conventional radiographs of the hip could predict hip fractures, we obtained pelvic radiographs on 9704 white women age 65 or older. We analyze the radiographs of all 162 women who subsequently suffered a hip fracture and 162 randomly selected women who did not. Adjusting for age, four measurements independently predicted hip fractures: reduced thickness of the femoral shaft cortex (odds ratio 1.7 per standard deviation; 95% confidence interval 1.2, 2.3) and of the femoral neck cortex (1.4 per standard deviation; 1.0, 1.9), reduction in an index of tensile trabeculae (2.0 per unit; 1.4, 2.9), and wider trochanteric region (1.4 per standard deviation; 1.0, 2.0). The combination of these four measurements predicted hip fracture at least as strongly as did measurement of bone density of the femoral neck (areas of the receiver-operating characteristic curve = 0.81 and 0.80, respectively). We conclude that simple measurements made on pelvic radiographs predict hip fractures as well as bone density of the hip.

Linear densitometry and digital image processing of proximal femur radiographs: implications for archaeological and forensic anthropology

Age- and sex-related patterns of proximal femur trabecular bone loss have previously been used to establish radiographic reference standards for estimating age at death for human skeletal remains. Such standards are of interest to both anthropologists and forensic scientists. However, osteopenia as a physiological phenomenon is dependent on numerous genetic, environmental, and cultural factors. Thus, while general age- and sex-related trends can be clearly observed for trabecular bone loss, such patterns also demonstrate marked variation among individuals of both sexes at all ages. Moreover, clinical evidence shows that rates of bone loss are not steady but episodic, and that radiographically "normal" (i.e., young adult) patterns of trabecular bone architecture can also exist in femora of older individuals, particularly within samples of African origin. In this study, adult proximal femur radiographs were used to explore patterns of age- and sex-related proximal femur cancellous bone involution among a sample of 66 African-American individuals from the Terry collection (33 males and 33 females), ranging in age from 19 to 71 years. The proximal femur radiographs of these subjects were analyzed by digital image processing (DIP), and the results were compared to those obtained by laser linear densitometric analyses (LDA) previously performed on the same series (Macchiarelli et al., 1987). Results of LDA and DIP analyses indicate (a) more pronounced bone density decrease in females; (b) sex- and site-specific structural patterns of proximal femur trabecular bone loss; (c) a high level of individual variability, in which predicted age deviated from real age by as much as 22.26 (males) and 30.78 years (females); (d) a moderate linear correlation with age for all the variables analyzed; and (e) an average discrepancy between known age and predicted age (measured by root mean squared residual values) of 10.34 (males) and 12.71 years (females) for the most satisfactory DIP analysis parameter (recorded at the center of the femoral neck in the equalized images). With regard to estimating adult age at death from radiographic images of proximal femora, it is argued that the amount of useful age information reported for this criterion has been overestimated.

Postmenopausal osteoporosis in Saudi women: A pilot screening

One hundred and ten radiographs of calcaneum were reviewed for postmenopausal osteoporosis in Saudi women. These patients had presented to the emergency room with unrelated complaints. The mean (+/- SD) age of this group was 58 (+/-8.9) years with a range of 45 to 80 years. Of these eighty-six (76%) patients had osteoporosis; of these, 42 had mild osteoporosis, 31 had frank osteoporosis, and 11 were diagnosed to have sever osteoporosis. Women with severe osteoporosis were significantly older than those with mild (P=0.0417) as those who were normal (P=0.002). This study indicates a high prevalence of postmenopausal osteoporosis in Saudi women and multicenter, large scale screening should be instituted to determine the incidence of postmenopausal osteoporosis among Saudi women.

Bone remodeling in hip fracture

Hip fracture incidence has shown strong upward secular trends in many societies with wide differences in age adjusted incidence between nations. Falls and reduced physical activity have emerged as the strongest risk factors in epidemiological studies, while clinical investigations have pointed to secondary hyperparathyroidism as an important candidate cause of the loss of femoral cortical bone in old age. Until recently there have been few studies performed directly on the region of interest in the proximal femur. Non-invasive methodology using 85Sr has now been developed by our group for measuring bone formation and (with concurrent serial DXA densitometry) resorption in the femoral neck. Bone turnover averaged about 8% annually in controls. A group of younger cases of femoral fracture showed similar indices of total and regional bone formation to a control group; but their resorption was higher. To further investigate this, a femoral neck bone biopsy technique has been developed which can be applied to fracture cases treated by arthroplasty. Preliminary studies have established that the anatomical asymmetry of the neck in cross-section is considerable and imposes restraints on the interpretation of smaller or incomplete femur biopsies. Prospects are quite good that, in the absence of tetracycline pre-labeling, mineralization can be studied by assessment of alkaline phosphatase-positive surfaces in cryostat sections. Moreover, such sections will permit study of other anatomically localized metabolic activities as well as antigen expression and osteocyte viability. Candidate mechanisms for the regional decline in bone quality as well as bone mass in subjects suffering hip fracture can now be investigated more effectively.

Osteoporosis and increased bone fractures in cerebrotendinous xanthomatosis

Significant osteoporosis determined by skeleton radiography and bone densitometry was found in 15 patients with cerebrotendinous xanthomatosis (CTX) whose mean age was 31 +/- 11 years. In three CTX patients, bone biopsies confirmed osteoporosis. Nine patients also sustained bone fractures following minimal trauma. Serum 25-hydroxyvitamin D ([25-OHD] 14.6 +/- 6.6 ng/mL v [normal] 30.4 +/- 8.0 ng/mL; P < .001) and 24,25-dihydroxyvitamin D ([24,25(OH)2D] 1.2 +/- 0.4 ng/mL v [normal] 2.7 +/- 0.8 ng/mL; P < .001) levels were low. Serum concentrations of 1,25(OH)2D, calcium, inorganic phosphorus, alkaline phosphatase, parathyroid hormone, and calcitonin were normal. Patients showed classic manifestations of CTX, including dementia, pyramidal and cerebellar insufficiency, peripheral neuropathy, cataracts, and tendon xanthomas associated with elevated serum cholestanol concentrations. These results demonstrate that extensive osteoporosis and increased risk of bone fractures are components of this inherited disease.

Metacarpal bone mass in systemic lupus erythematosus

We report the prevalence of metacarpal cortical thinning in systemic lupus erythematosus (SLE). Fifty-eight ambulant female patients attending a lupus clinic (mean age 32.4 years), were found to have significant thinning of metacarpal cortices (p < 0.05) when compared with 63 normal females (mean age 34.1 years). However, metacarpal bone mass was within the normal range. Measurements were made at 6 metacarpals of the 2 hands using a computer-aided technique (digitized radiogrammetry). Femoral cortical width and Singh index at the left femur, as well as the vertebral index at L3 were also recorded. The trabecular indices were in the range of normality, but the SLE group had more patients in the immediately pre-osteopenic range. Metacarpal bone loss was not related to disease duration or corticosteroid therapy. The prevalence of osteopenia in SLE is probably underestimated and the pathogenesis is likely to be multifactorial.

Pattern of bone loss of the proximal femur: a radiologic, densitometric, and histomorphometric study

The pattern of bone loss in the proximal femur was studied in 141 cadaveric femora from 36 women and 39 men ranging from 27 to 89 years of age. Bone mineral density (BMD) of the femoral neck, greater trochanter, Ward's triangle, and tensile and compressive stress regions were measured by dual photon absorptiometry. Radiographs were graded by Singh's method. Histomorphometry of tensile and compressive trabecular areas was performed on ground midsection of the methylmethacrylate-embedded whole proximal femur. Although Singh index had some correlation with BMD of the femoral neck, the various BMD measurements showed that all regions lost bone to the same extent; in particular, no selective bone loss was found at low stress regions (tensile trabeculae or Ward's triangle). Histomorphometry revealed that most of the trabecular bone loss of the proximal femur is attributable to a decrease in thickness of individual trabeculae.

Osteoporosis: diagnosis by plain chest film versus dual photon bone densitometry

Readers of chest radiographs often comment on the presence of osteoporosis. We have hypothesized that diagnoses of osteoporosis from chest films are not reliable even when made by experienced radiologists. To test this hypothesis, we had nine radiologists estimate the degree of bone density seen on 45 lateral chest films. We compared their estimates of bone density to the results of dual photon bone densitometry of the lumbar spine. We found that there was little ability to accurately diagnose osteoporosis by chest film since the group of nine readers achieved accuracies ranging from 0.59 to 0.64. Therefore, we feel it is unjustified to comment upon the presence or absence of osteoporosis on the basis of chest films.

Osteoporosis and fracture patterns. A study of split-compression fractures of the lateral tibial condyle

The initial radiographs of 42 split-compression fractures of the lateral tibial condyle were studied. The breadth of the wedge-shaped fragments, measured at the level of the articular surface, was found to decrease with increasing severity of osteoporosis. Ranks were assigned to the breadths and average ranks to the grades (low ranks for normals). Spearman's rank correlation co-efficient was -0.507, which is significant at the 1% level. The length of the fragments showed a similar decrease with advancing bone loss. Rank correlation with the degree of osteoporosis was -0.393, which is significant at the 5% level. These results support the hypothesis that the fracture pattern depends on the changes in bony architecture which results from osteoporosis.

The effects of walking on the cross-sectional dimensions of the radius in postmenopausal women

This report deals with the analysis of data from a 3-year clinical trial on the effect of walking on postmenopausal bone loss. Two hundred fifty-five women, with an average age of 57 at entry, were randomized into two groups, a walking and a control group. Bone measures in the shaft of the radius were carried out with a CT scanner in search of generalized skeletal effects rather than effects localized to the bones of the leg. Although bone density losses were comparable in the two randomized groups, changes in the cross-sectional area of the radius were significantly greater in the walkers with high grip strength (greater than 25 Kg) than in the controls with comparable high grip strength which corresponded to the upper half range of the grip-strength distribution. It is concluded that the moderate activity of walking exerted systemically positive effects on the radius which, within the protocol of the study, could be substantiated only when synergized with inherent muscle strength.

Fixed-head and bipolar hip endoprostheses. A retrospective clinical and roentgenographic study

A retrospective review of 1,001 hip hemiarthroplasties was performed. The prosthetic designs were grouped into fixed-head types (682 cases) and bipolar types (319 cases) for comparison. The main indications for operation were femoral neck fracture and avascular necrosis of the femoral head. Clinical and roentgenographic data for different follow-up periods were compared between prosthetic types, using multivariate analysis. Roentgenographic loosening of the femoral component was noted in 25.4% of cases but was significantly higher (P less than .05) in the bipolar groups for a follow-up period less than 2 years, regardless of the method of fixation. The acetabular erosion rate was significantly higher (P less than .05) in the fixed head group, but this finding was related to length of follow-up period, bone porosity, and prosthesis/acetabulum fit. The reoperation rate, including revision to total hip arthroplasty, was higher in the fixed-head group (12.5%) than the bipolar group (7.2%). Based on Kaplan-Meier survivorship analysis, 13.7% of the bipolar and 22.9% of the fixed-head hip endoprostheses are expected to be reoperated 8 years after initial implantation. Cement fixation of the femoral component led to a higher prosthesis survival rate, regardless of type. Both prosthetic types are useful in hip surgery, but the bipolar type appears to be indicated in younger and more active patients, whereas the fixed-head design is more suitable for older patients with femoral neck fractures.

Lactose absorption, milk consumption, and fasting blood glucose concentrations in women with idiopathic osteoporosis

Lactose tolerance tests were performed in 33 women with osteoporosis and 33 control women matched for age. A questionnaire was used to elicit any history of milk intolerance and the subjects' daily intake of calcium derived from milk and dairy products. Eleven patients and four controls gave a history of milk intolerance (p less than 0.01); 13 patients had lactose malabsorption compared with four controls (p less than 0.01). The daily intake of calcium derived from milk was significantly lower in patients (125 (SEM 20) mg v 252 (43) mg; p less than 0.05). Curves of blood glucose concentrations during the lactose tolerance test in subjects with lactose malabsorption were significantly flatter in patients than controls (p less than 0.05). The fasting blood glucose concentration was higher (5.44 (0.17) mmol/l (98 (3) mg/100 ml) in the patients than the controls (4.88 (0.11) mmol/l (88 (2) mg/100 ml); p less than 0.05), although body weight was significantly lower (61.6 (2.2) kg v 66.3 (1.6) kg; p less than 0.05). Absorption of lactose is significantly impaired in women with "idiopathic" osteoporosis; this combined with low consumption of milk and a subclinical disorder of glucose metabolism may be a major factor in the development of idiopathic osteoporosis in women.

Radiographic changes in the clavicle and proximal femur and their use in the determination of skeletal age at death

Visually seriated radiographs of the proximal femur, proximal humerus, clavicle, and calcaneus from 130 individuals from the Hamann-Todd collection were examined as indicators of skeletal age at death. The clavicle demonstrated the most consistent relationship to age in both sexes. The same radiographs were also seriated by size-normalized optical density as a means of establishing relative radiolucency. In this context, visual seriation proved superior. The four sites studied showed strong divergence in response to age. Since each was sampling bone response from the same individual, it is concluded that bone loss is highly site specific. This demonstrates the individual character of specific skeletal sites. Visual inspection of clavicular radiographs, seriated on a populational basis, provides age estimates that are comparable to anatomical age indicators and provides independent estimates of skeletal age when included in the summary age method (1985: Am. J. Phys. Anthropol. 68:1-14).

Postmenopausal osteoporosis. A heterogeneous disorder as assessed by histomorphometric analysis of Iliac crest bone from untreated patients

Twenty-six women with untreated postmenopausal osteoporosis underwent iliac crest biopsy following tetracycline-labeling and mineral metabolism studies. Histomorphometric assessment of their bone remodeling rates, including formation determined by the tetracycline-labeling technique, revealed considerable variation. Eight women had no evidence of active bone formation (inactive remodeling osteoporosis), whereas the others showed a spectrum of bone formation rates (active remodeling osteoporosis). Clinical and biochemical studies failed to predict the histomorphometric findings. Postmenopausal osteoporosis is a histologically heterogeneous disorder with morphologic expression in bone that cannot be predicted by single or combined routine clinical and laboratory parameters. Bone biopsy, necessary to identify the histologic lesion and assess skeletal dynamics, may prove to be important for optimal therapy of osteoporosis, as a variety of agents--with different effects on bone remodeling--are available.