Validated measurement of periarticular bone mineral density at the knee joint by dual energy x ray absorptiometry

OBJECTIVE: The association of inflammatory arthritis with loss of periarticular bone mineral density (BMD) has been well established. However, changes in bone density cannot be quantified by conventional radiography. This study aimed at developing a new technique for measurement of periarticular bone density at the knee joint by dual energy x ray absorptiometry (DXA) and assessing the precision of this technique for selected areas around the knee. METHODS: To validate this technique for bone density assessment in both patient and control subjects, knee joints from healthy subjects and patients with inflammatory arthritis were selected for study. Posteroanterior (PA) and lateral scans of both knees were acquired with the Hologic 4500 elite bone densitometer. Each scan was repeated three times, with repositioning between scans. Knee scans were obtained with the forearm software and evaluated by subregion analysis. Seven femoral and seven tibial subregions of interest (ROIs) were selected on PA scans. Six ROIs were selected on lateral scans. Precision was determined for each ROI selected. RESULTS: 14 knee joints were studied in each group. Precision, expressed as percentage coefficient of variation (CV%), varied widely between subregions. PA scans were most appropriate for measurement of femoral bone density (CV% = 1.89-2.64%), whereas the best value obtained for ROIs within the tibia was on the lateral scan, where CV% for measurement of the proximal 5 mm was 2.67% in the patient group. CV% for BMD of the patella was excellent at 0.84% in the patient group. CONCLUSION: This new application of DXA can be used to measure periarticular bone density at the knee joint. Regions within the distal femur and patella have been identified as the optimal areas to study     

Measurement of hand bone mineral density in early rheumatoid arthritis using dual energy X‐ray absorptiometry

Aims: The earliest radiological change in rheumatoid arthritis (RA) is periarticular osteopenia, which occurs prior to the appearance of erosions and clinically apparent deformities. The aim of the study was to measure periarticular bone mineral density (BMD) in the hands of patients with early RA, using dual energy X‐ray absorptiomentry (DEXA) and to correlate this with markers of disease activity and radiological progression. Methods: The study population (n = 50) of patients with RA of < 3 years duration underwent measurement of BMD of the non‐dominant hand, femoral neck and lumbar spine and clinical assessment at baseline, 6 and 12 months. Hand radiographs were performed at baseline and 12 months. Thirty age‐ and sex‐matched controls also underwent measurement of BMD of the non‐dominant hand, femoral neck and lumbar spine. Results: Hand BMD correlated strongly with sex, height, weight and lumbar and femoral neck BMD in both RA subjects and controls. Baseline hand BMD in RA subjects correlated with baseline serum C‐reactive protein (r = ?0.36, P = 0.01) and 12‐month radiographic score (r = 0.36, P = 0.02). There were small non‐significant decreases in hand, femoral neck and lumbar spine BMD over the 12‐month period. Conclusion: Hand BMD measurement using DEXA is a reproducible, well‐tolerated procedure that warrants further investigation as a component of routine assessment in early RA.     

Assessment of the effect of oral corticosteroids on bone mineral density in systemic lupus erythematosus: a preliminary study with dual energy x ray absorptiometry.

Dual energy x ray absorptiometry and a wide range of blood and urine tests were used to assess the propensity of patients with systemic lupus erythematosus to develop an impairment of bone mineral density. Surprisingly, in this preliminary study no significant differences in bone mineral density were found when patients taking 10 mg or more of prednisolone for six months or longer were compared with those who had never taken prednisolone.     

Bone mineral density in patients with hyperthyroidism measured by dual energy X-ray absorptiometry

OBJECTIVE We assessed the changes of bone mass in patients with hyperthyroidism by measuring bone mineral density using a new method, dual energy X-ray absorptiometry. DESIGN The values of bone mineral density in patients with hyperthyroidism were compared with data obtained from the controls, and we assessed the correlation analysis between bone mineral density and several metabolic parameters. PATIENTS We studied 52 Japanese patients with hyperthyroidism (20 males, 32 females). Healthy normal subjects served to establish the mean bone mineral density In the healthy Japanese population (Shiraki et al. 1991). MEASUREMENT Bone mineral density was assessed by the measurement of lumbar vertebrae and femur by dual energy X-ray absorptiometry. The bone mineral density of vertebrae for each patient was calculated as the percentage of the mean value (% bone mineral density) obtained from an age and sex-matched control group. Blood was drawn to measure the levels of serum calcium, phosphorus, creatinine, alkaline phosphatase, free T3, free T4, TSH, TSH receptor antibody, parathyroid hormone, and serum osteocalcin. RESULTS The percentage bone mineral density of vertebrae in patients was 92.6 as compared with that of normal controls, and was inversely correlated with serum TSH receptor antibody, osteocalcin, and alkaline phosphatase. CONCLUSIONS These findings suggest that bone mineral density is decreased in patients with hyperthyroidism and that TSH receptor antibody, osteocalcin, and alkaline phosphatase are sensitive markers of bone metabolism alterations in hyperthyroidism.     

DEXA测定老年人骨密度186例报告

于１９９５年９月体检人群中，随机采用Ｈｏｌｏｇｉｃ２０００型双能Ｘ线骨密度仪（ＤＥＸＡ）测量１８６例骨密度。结果提示年龄每增５岁，髋部、Ｗａｒｄ区及腰椎１～４三处之骨密度递减（Ｐ＜０．０５）。≥６０岁组之骨峰骨量亦随增龄而降低（Ｐ＜０．０１）。骨峰值在≥６０岁组下降２个标准差以上者占６１．３％。女性除Ｗａｒｄ区骨量，均低于男性（Ｐ＜０．０１）。     

Bone mineral density in juvenile dermatomyositis: Assessment using dual x‐ray absorptiometry

Objective

To determine the bone mineral density (BMD) status of our juvenile dermatomyositis (DM) population and to compare the frequency of osteopenia in patients with active disease requiring corticosteroids with that in patients with inactive disease who are not receiving corticosteroids.

Methods

Medical charts of all children diagnosed as having juvenile DM at our institution between 1989 and 1999 were reviewed for demographic and clinical data, including disease activity and duration of corticosteroid therapy. BMD measurements of the lumbar spine (L1–L4) were performed using dual x‐ray absorptiometry (DXA). Z scores were calculated from the BMD data for comparison with published normative data.

Results

A total of 15 patients were assessed: 10 with active disease, and 5 with inactive disease who had not taken corticosteroids for an average of 6.0 years (range 3.4–8.1 years). Baseline BMD measurements demonstrated osteopenia or frank osteoporosis in the majority of patients, including 6 of the 10 patients with active disease and 4 of the 5 patients whose disease was in remission. Fourteen patients had serial BMD measurements. Persistent or worsening osteopenia was documented in all patients who had ongoing active disease, except for 3 patients who had been treated with bisphosphonates because of vertebral compression fractures.

Conclusion

Osteopenia is common in patients with juvenile DM, and it usually worsens with ongoing disease. It can persist for many years after the disease enters remission. Bisphosphonates appeared to beneficially affect bone mineralization in our patients. Treatment to prevent the long‐term complications of osteoporosis in patients with juvenile DM should be considered and requires further study.

     

Measurement of periarticular bone mineral density in the hands of patients with early inflammatory arthritis using dual energy x-ray absorptiometry

Hand bone densitometry is more sensitive than standard radiology in the measurement of disease-related bone damage in early arthritis. Most studies employing dual energy x-ray absorptiometry (DXA) have evaluated the whole hand. The aim of this study was to evaluate a method that quantified bone density in regions of interest that were confined to the juxta-articular areas of metacarpo-phalangeal (MCP) and proximal interphalangeal (PIP) joints. Patients with inflammatory arthritis affecting the hands were selected for study. Postero-anterior (PA) scans of selected juxta-articular sub-regions were acquired using a Hologic 4500 Elite bone densitometer and forearm software. Each hand was scanned three times in immediate succession with repositioning between scans. The six selected sub-regions included the periarticular regions of the second, third, and fourth MCP and PIP joints. Sub-regions of different dimensions (4 and 5 mm proximal and distal to the joint space) were assessed at each joint. Coefficients of variation (CV) were calculated for bone mineral density (BMD) and bone mineral content (BMC) of each selected sub-region. Eighty four individual hand joints in seven patients were evaluated three times. Precision values ranged between 0.89% and 2.37% for BMD and between 1.38 and 3.26 for BMC measurements. BMD measurements of MCP joints were more precise than PIP joints. BMD measurements of 10-mm sub-regions were more precise than 8-mm sub-regions. The precision value for the net average BMD measurement of the six sub-regions evaluated was 0.78% for 8-mm sub-regions and 0.73% for 10-mm sub-regions. Net average BMC measurements had CV values of 1.11% and 1.08%, respectively. DXA can be used to reliably measure periarticular BMD and BMC of small joints in the hands in patients with early inflammatory arthritis. Precision values for quantifying juxta-articular bone approximated BMD measurements of the spine.     

Prediction of fractures in perimenopausal women: a comparison of dual energy x ray absorptiometry and broadband ultrasound attenuation.

OBJECTIVE: To consider whether bone mineral density (BMD) measurements can predict traumatic fractures occurring in perimenopausal women. METHODS: One thousand perimenopausal women called up for screening underwent both dual energy x ray absorptiometry (DXA) of the spine and hip, and broadband ultrasound attenuation (BUA) of the heel. Two years later, they were sent a questionnaire to discover those who had since had a fracture, and compare them with those who had not. RESULTS: About 2% of the women had sustained a fracture in the two years since attendance for screening. Fractures in this age group can be predicted weakly, but significantly, by bone mass measurements using DXA and BUA (odds ratios from 1.4 to 2.1). The lumbar spine appeared to be one of the best predictive sites (odds ratio for 1 SD reduction in BMD 2.1 (95% confidence interval 1.2 to 3.8)), but no significant differences were found between the areas under the curve in receiver operator characteristic (ROC) analysis. CONCLUSION: In this preliminary study it appeared that bone mass measurements are predictive of perimenopausal traumatic fractures in addition to postmenopausal fractures related to osteoporosis. DXA of the lumbar spine did not perform significantly better than BUA. The number of fractures occurring was low, however, and further long term follow up is required to confirm the finding.     

Bone quality and bone mass as assessed by quantitative ultrasound and dual energy x ray absorptiometry in women with rheumatoid arthritis: relationship with quadriceps strength

OBJECTIVE: To examine relationships of bone quality as assessed by quantitative ultrasound (QUS) and bone mineral density (BMD, g/cm(2)) with quadriceps strength (QS) in women with rheumatoid arthritis (RA). METHODS: Sixty seven women with RA according to the 1987 American College of Rheumatology (ACR) criteria were examined. Mean (SD) age was 62 (13) years, mean disease duration 15 years. Most were or had been receiving glucocorticoid treatment. Calcaneal bone quality expressed as speed of sound (SOS, m/s), broadband ultrasound attenuation (BUA, dB/MHz), and stiffness was measured by QUS. BMD of the femoral neck, spine, and distal forearm was measured by dual energy x ray absorptiometry (DXA). Maximal voluntary isokinetic quadriceps strength (Nm) was assessed by isokinetic dynamometry. Pain was recorded on a visual analogue scale (VAS), disability was scored by the Stanford Health Assessment Questionnaire (HAQ), and the degree of physical impairment was expressed by the Steinbrocker index (SI). RESULTS: In multiple regression analyses, QS predicted SOS, BUA, and stiffness (r(partial) ranging from 0.36 to 0.45, p<0.005) and femoral neck BMD (r(partial)=0.30, p<0.05) independently of age, height, weight, disease duration, HAQ, VAS, SI, and cumulative steroid dose. BMD of the spine and distal forearm was not associated with QS. After adjustment for covariates, women with subnormal BMD of the femoral neck (T score <-1), had a 20% lower QS than those with normal BMD (p<0.0001). CONCLUSIONS: Calcaneal bone quality and femoral neck BMD were associated with QS in women with RA. This finding indicates that physical activity including muscle strengthening exercises may play a part in the prevention of bone loss in these patients.     

Bone mineral density,biochemical and hormonal profiles in suboptimally treated children and adolescents with beta-thalassaemia disease

OBJECTIVE: Thalassaemia/haemoglobinopathy is a hereditary disease causing increased erythropoiesis and expansion of the bone marrow cavity. As a consequence, there is a reduction in trabecular bone tissue resulting in osteopenia/osteoporosis. The present study was performed to assess bone mineral density (BMD) in children and adolescents with beta-thalassaemia disease and to determine biochemical and hormonal changes that may affect BMD. METHODS: Forty-eight children and adolescents with beta-thalassaemia were divided into two groups, transfusion-dependent (TD) (n = 16) and transfusion-independent (TI) (n = 32). All patients were treated suboptimally. BMD was determined by dual-energy X-ray absorptiometry. Bone maturation was assessed by radiographic bone age (BA). Blood and urine samples were obtained for the determination of biochemical and hormonal profiles, which included PTH, 25-hydroxyvitamin D (25-OHD), osteocalcin, bone-specific alkaline phosphatase, IGF-1, fT4, TSH and urine deoxypyridinoline. RESULTS: Most of the patients were short and underweight, and they had delayed BA with mean Z-scores of -2.77 in the TD and -2.04 in TI groups. The mean Z-scores of BMD in the TD vs. TI groups of total body, radius, femoral neck and lumbar spine were -2.09 vs.-1.49, -0.73 vs. -0.54, -1.93 vs.-1.17 and -3.45 vs.-2.43, respectively. Although the means BMD values in the TD group were lower than those in the TI group, they were not significantly different. Mean serum IGF-1 levels were lower in the TD than the TI groups, 11.6 and 24.9 nmol/l, respectively (P < 0.05). Other biochemical and hormonal profiles did not differ between these two groups. CONCLUSIONS: Patients with undertransfused severe beta-thalassaemia had more bone marrow expansion, lower serum IGF-1 levels and more delayed bone age than did patients with untransfused moderately severe beta-thalassaemia. Therefore, the severity of the disease appeared to be a primary factor for low bone mineral density in undertransfused patients in association with bone age delay and low serum IGF-1.     

Bone mineral density in juvenile dermatomyositis: assessment using dual x-ray absorptiometry

OBJECTIVE: To determine the bone mineral density (BMD) status of our juvenile dermatomyositis (DM) population and to compare the frequency of osteopenia in patients with active disease requiring corticosteroids with that in patients with inactive disease who are not receiving corticosteroids. METHODS: Medical charts of all children diagnosed as having juvenile DM at our institution between 1989 and 1999 were reviewed for demographic and clinical data, including disease activity and duration of corticosteroid therapy. BMD measurements of the lumbar spine (L1-L4) were performed using dual x-ray absorptiometry (DXA). Z scores were calculated from the BMD data for comparison with published normative data. RESULTS: A total of 15 patients were assessed: 10 with active disease, and 5 with inactive disease who had not taken corticosteroids for an average of 6.0 years (range 3.4-8.1 years). Baseline BMD measurements demonstrated osteopenia or frank osteoporosis in the majority of patients, including 6 of the 10 patients with active disease and 4 of the 5 patients whose disease was in remission. Fourteen patients had serial BMD measurements. Persistent or worsening osteopenia was documented in all patients who had ongoing active disease, except for 3 patients who had been treated with bisphosphonates because of vertebral compression fractures. CONCLUSION: Osteopenia is common in patients with juvenile DM, and it usually worsens with ongoing disease. It can persist for many years after the disease enters remission. Bisphosphonates appeared to beneficially affect bone mineralization in our patients. Treatment to prevent the long-term complications of osteoporosis in patients with juvenile DM should be considered and requires further study.     

Normal parathyroid function with decreased bone mineral density in treated celiac disease.

Decreased bone mineral density (BMD) has been reported in patients with celiac disease in association with secondary hyperparathyroidism. The present study investigated whether basal parathyroid hormone (PTH) remained elevated and whether abnormalities of parathyroid function were still present in celiac disease patients treated with a gluten-free diet. Basal seric measurements of calcium and phosphate homeostasis and BMD were obtained in 17 biopsy-proven patients under treatment for a mean period of 5.7+/-3.7 years (range 1.1 to 15.9). In addition, parathyroid function was studied with calcium chloride and sodium citrate infusions in seven patients. Basal measurements of patients were compared with those of 26 normal individuals, while parathyroid function results were compared with those of seven sex- and age-matched controls. Basal results were similar in patients and controls except for intact PTH (I-PTH) (3.77+/-0.88 pmol/L versus 2.28+/-0.63 pmol/L, P<0.001), which was higher in the former group but still within normal limits. Mean 25-hydroxy vitamin D and 1,25-dihydroxy vitamin D values were normal in patients. Parathyroid function results were also found to be similar in both groups. Compared with a reference population of the same age (Z score), patients had significantly lower BMDs of the hip (-0.60+/-0.96 SDs, P<0.05) and lumbar spine (-0.76+/-1.15 SDs, P<0.05). T scores were also decreased for the hip (-1.3+/-0.9 SDs, P<0.0001) and lumbar spine (-1.4+/-1.35 SDs, P<0.0001), with two to three patients being osteoporotic (T score less than -2.5 SDs) and seven to eight osteopenic (T score less than -1 SDs but greater than or equal to -2.5 SDs) in at least one site. Height and weight were the only important determinants of BMD values by multivariate or logistical regression analysis in these patients. The results show higher basal I-PTH values with normal parathyroid function in treated celiac disease. Height and weight values are, but I-PTH values are not, an important determinant of the actual bone mass of patients. Normal parathyroid function in treated patients suggests a lack of previous severe secondary hyperparathyroidism and/or complete adaptation to prior changes in parathyroid function.     

Bone loss in unclassified polyarthritis and early rheumatoid arthritis is better detected by digital x ray radiogrammetry than dual x ray absorptiometry: relationship with disease activity and radiographic outcome

OBJECTIVE: To compare changes in regional bone mineral density (BMD) of the metacarpal joints measured by dual x ray absorptiometry (DXA) and digital x ray radiogrammetry (DXR) in relation to disease activity and radiographic outcome in a two year follow up study of patients with early RA and unclassified polyarthritis. PATIENTS AND METHODS: 72 patients with symmetrically swollen and tender second and third metacarpophalangeal or proximal interphalangeal joints for at least four weeks and less than two years were included. 51 patients fulfilled the ACR criteria for RA. 21 patients had unclassified polyarthritis. The patients with RA were divided into groups according to mean disease activity, average glucocorticoid dose, and MRI and x ray detected bone erosions in the hands. Clinical and biochemical measurements were made every month and an x ray examination of the hands and BMD of the metacarpal joints every six months. RESULTS: DXR BMD decreased significantly only in patients with RA from month 6 and was associated with the mean disease activity. Patients with RA and erosive as well as non-erosive disease showed a significant decrease in the rate of bone loss, greatest in those with erosive disease. No changes in BMD measured by DXA were seen in any patient group. CONCLUSION: DXR is a useful measure of the destructive disease activity in patients with RA and unclassified polyarthritis, providing valuable information about bone changes associated with disease activity and erosive disease in early RA. DXR is better than DXA for detecting and monitoring periarticular osteoporosis of the metacarpal bone.     

Low circulating insulin-like growth factor I in coeliac disease and its relation to bone mineral density.

BACKGROUND: Patients with coeliac disease have low bone mineral density (BMD), but the underlying mechanisms are unclear. Our aim was to study circulating insulin-like growth factor I (IGF-I) and its possible relationship to BMD in adults with untreated coeliac disease and after 1 year on a gluten-free diet. METHODS: In 29 consecutive adult coeliac patients fasting IGF-I and BMD (n = 28) were examined before and 1 year after starting a gluten-free diet. Intact parathyroid hormone (PTH) was measured (n = 20) before the gluten-free diet was started. RESULTS: Untreated coeliac patients had lower IGF-I values than controls matched for age and sex, and their BMD was low. A relationship was observed between BMD and IGF-I but not independent of age and body mass index. During the 1st year on a gluten-free diet BMD increased (P < 0.001), as did the circulating IGF-I levels in 21 of the 29 patients (P = 0.078). In the subgroup of 14 patients with normal initial PTH the increase in IGF-I correlated positively with the increase in BMD (femoral trochanter, r = 0.62, P < 0.05, and lumbar spine, r = 0.70, P < 0.02). CONCLUSIONS: BMD and circulating IGF-I levels are low in adults with untreated coeliac disease. In patients with normal initial PTH level there is an association between the change in BMD and circulating IGF-I, although this parallel increase may not be causally connected.     

Measurement of bone mineral content of the lumbar spine by dual energy x-ray absorptiometry in normal children: correlations with growth parameters

The bone mineral density (BMD) of the lumbar spine (L1-L4) was measured by dual energy x-ray absorptiometry (Hologic QDR 1000) in 135 healthy caucasian children, aged 1-15 yr, and values were correlated with age, height, weight, body surface, bone age, pubertal status, calcium intake, vitamin D supplementation, and serum bone gla protein. BMD increased with age in children of both sexes (r = 0.88; P less than 0.001) from 0.446 +/- 0.048 g/cm2 at 1 yr to 0.625 +/- 0.068 g/cm2 at 10 yr and 0.891 +/- 0.123 g/cm2 at 15 yr of age. The increase was steeper at the time of puberty, reaching values above 0.80 g/cm2 after puberty was achieved. There were no significant differences between boys and girls, except at the age of 12 yr when BMD was higher in girls than in boys (P = 0.007), probably because of the earlier onset of puberty in females. BMD was also highly correlated with height, weight, body surface, and bone age. BMD was not correlated with calcium intake when age was held constant, nor with vitamin D supplementation. Serum bone gla protein showed a steady increase during childhood, with peak values at 11-12 yr of age, and was weakly but significantly correlated with BMD (r = 0.27; P = 0.007). Because of low irradiation exposure, rapid scanning, and high precision, dual energy x-ray absorptiometry is a noninvasive method which is well adapted to the child. It should be helpful in the investigation and follow-up of children with diseases impairing bone metabolism.     

Bone mineral density in patients with rheumatoid arthritis: relation between disease severity and low bone mineral density

OBJECTIVE: To examine variables associated with bone mineral density (BMD) in patients with rheumatoid arthritis (RA). METHODS: We investigated 373 patients with low to moderately active RA. Patients with low disease activity were recruited from a cohort of patients in clinical remission. Patients with moderately active disease were included in a trial comparing the effects of long term high intensity exercise programme and conventional physical therapy. Demographic and clinical data were collected. Bone mineral density (BMD) was measured by means of dual x ray absorptiometry (DXA). Associations between demographic and clinical measurements on the one hand and BMD on the other were investigated in regression analyses. RESULTS: The patient group consisted of middle aged, mainly female, patients. The median (interquartile range) disease duration was 7 (4 to 13) years, the mean disease activity score (standard deviation) was 3.2 (1.4). Of the group, 66% was rheumatoid factor positive, and 83% (n = 304) had never used corticosteroids. The median Larsen score of hands and feet was 27 (5 to 61). Greater age and low body mass index were related to low BMD at the hip and spine. High Larsen score for hands and feet was significantly associated with low BMD at the hip. The use of corticosteroids was not independently associated with BMD. The results of the multiple regression analyses also applied to the subgroup of corticosteroid naive patients. CONCLUSION: BMD data of patients with low to moderately active RA demonstrated an association between high radiological RA damage and low BMD at the hip, which suggests an association between the severity of RA and the risk of generalised bone loss, which also occurred in corticosteroid naive patients.     

Changes in bone mineral density in patients with Paget's disease treated with risedronate

OBJECTIVES—To study changes in bone mineral density (BMD) in patients with Paget's disease of bone treated with risedronate.
METHODS—Whole body dual energy x ray absorptiometry (DXA) scans were carried out on 20 patients with Paget's disease treated with oral risedronate. DXA scanning was carried out at baseline and 11 months. Whole body bone mineral content (BMC) was measured. In addition, regions of interest were drawn around the skull, individual lumbar vertebrae, hemipelvis, femora, and tibiae to obtain BMD for these sites. An uncoupling index was also calculated as the area under the curve for serum alkaline phosphatase (ALP) divided by the area under the curve for hydroxyproline excretion (HYPRO) for the period of treatment.
RESULTS—Median whole body BMC increased from 3057 g to 3156 g (p < 0.001) resulting from an increase in pagetic and non-pagetic BMD. From the analysis of regions of interest it was found that pagetic trabecular bone showed the largest increase in BMD. The pretreatment HYPRO and the uncoupling index were significantly related to the change in BMD for all pagetic sites for a patient (r = 0.65 , p < 0.01 and r = 0.57, p < 0.05 respectively).
CONCLUSION—Bisphosphonate treatment of Paget's disease results in an increase in BMD of pagetic bone without redistribution of mineral from non-pagetic bone. The remodelling space and extent of uncoupling are significantly related to increases in BMD at pagetic sites.