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PubMedDate not supplied

Clinical implications of catheter variability on neonatal continuous arteriovenous hemofiltration.

The clinical impact of catheter diameter variability on performance of neonatal continuous arteriovenous hemofiltration (CAVH) systems was shown by demonstration of the effect of catheter inner diameter on catheter and CAVH system blood flow. Diameter of 3.5 Fr and 5 Fr catheters was determined by experimental measurement of catheter flow-pressure drop relationship with known equations for fluid flow. Physical measurements verified the accuracy of the calculated diameters. These diameters were then used in a mathematical simulation to describe blood flow through an entire neonatal CAVH system and predict clinical performance. Catheters of 5 Fr caliber had a 39% variation in diameter among manufacturers, resulting in a 370% variation in blood flows; 3.5 Fr catheters had a 29% variation in internal diameter with a corresponding blood flow variation of 290%. Computer simulation of a neonatal CAVH system revealed a maximum blood flow of 0.8-3.0 ml/min with available 5 Fr catheters. This wide variation is probably responsible for the lack of consistent results in neonatal CAVH systems to date.

Catheterization, Peripheral↗
PubMed1995

Topographical evaluation of skin perfusion patterns in peripheral arterial occlusive disease by means of computer-assisted fluorescein perfusography.

OBJECTIVE: To evaluate the clinical impact of computer-assisted fluorescein perfusography in peripheral arterial occlusive disease (PAOD). DESIGN: Foot and calf skin perfusion was visualised by intravenous fluorescein injection. Fluorescein influx was recorded photographically and converted into functional images of fluorescein appearance times (AT) by means of digital film processing. SETTING: Vascular Laboratory of Clinic for Vascular Disease. MATERIALS: 249 patients with PAOD. Among 481 limbs studied, 83 legs presented with patent arteries, 70 with asymptomatic obstructions (Stage I), 170 with claudication (Stage II) and 158 with rest pain and skin lesions (Stage III/IV). CHIEF OUTCOME MEASURES: Forefoot and calf mean ATs and standard deviations (SD) served as arbitrary measures of regional skin perfusion rates and their homogeneity, respectively. MAIN RESULTS: In the control legs, a homogeneous and fast fluorescence appearance was observed (medians at the foot: AT33.4 s, SD 3.6). In stage II disease, AT (39.9 s, SD 5.6) were slightly impaired as compared to limbs with patent arteries or stage I disease (p < 0.01). Ninety-seven out of the 158 legs in stage III/IV could be managed by conservative therapy. According to fluorescein-perfusography, they did not differ from stage II disease (AT 38.8 s, SD 6.1). Sixty-one limbs were clinically affected by critical ischaemia. They exhibited a markedly delayed and heterogenous fluorescein influx at the foot (AT 77.3 s, SD 26.5, p < 0.01 vs all other groups). Non-fluorescent areas occurred in 53% compared to only 1% of limbs with and without critical ischaemia, respectively. Retrospectively, predictive values of fluorescein perfusography in identifying a critical limb ischaemia (accuracy 93%) were superior to the ankle systolic arterial pressure determination (accuracy 80%). CONCLUSIONS: Fluorescein perfusography seems to be of diagnostic and prognostic use in PAOD in stage III/IV where inflammatory and ischaemic patterns of dye appearance can be distinguished.

Adult↗
PubMed2002

Mechanical strength of the proximal femur as predicted from geometric and densitometric bone properties at the lower limb versus the distal radius.

This experimental study compares geometric and densitometric properties of cortical and trabecular bone at the lower limb and the distal radius with those at the femoral neck, and evaluates their ability to predict mechanical failure loads of the proximal femur. One hundred five cadavers were examined with peripheral quantitative computed tomography (LpQCT), with measurements being performed in situ at the distal radius (4%, 20%, 33%), at the distal and proximal tibia, at the tibial and femoral shaft, and at the distal femur. Ex situ measurements were obtained at the femoral neck and at the proximal femoral shaft. Pairs of femora were mechanically tested in a vertical loading and a side impact (fall) configuration. The total (cross-sectional) bone mineral content and trabecular density, but not the cortical properties, displayed a higher association between the femoral neck and the peripheral lower limb than between the neck and the distal radius. Approximately 50%-60% of the variability of femoral failure loads (and >80% of trochanteric side impact fractures) were predicted by in vitro measurements at the neck. Geometric cortical parameters and density contributed independently and significantly to femoral strength. Measurements at the peripheral skeleton explained, however, only 30%-45% of the variability of femoral failure, with no significant difference between the lower limb and the distal radius. At peripheral sites, a combination of geometric and densitometric variables was slightly superior to bone mineral content alone in predicting failure in vertical loading, but this was less evident for cervical side impact fractures. The results show that a stronger association of total bone mineral content and trabecular density between the femoral neck and the lower limb does not translate into improved prediction of femoral strength from measurements at the lower limb vs. those at the distal radius.

Aged↗
PubMedDate not supplied

Comparison of three arterial pulse waveform classification techniques.

Peripheral pulse waveforms can become stretched and damped with increasing severity of peripheral vascular disease (PVD) and hence could provide valuable diagnostic information. This study compares the diagnostic performance of 3 established classification techniques (a linear discriminant classifier, a k-nearest neighbour classifier, and an artificial neural network) for the detection of lower limb arterial disease from pulse waveforms obtained using photoelectric plethysmography (PPG). Pulse waveforms and pre- and post-exercise Doppler ultrasound ankle to brachial pressure indices (ABPI) were obtained from patients attending a vascular measurement laboratory. A single PPG pulse from each big toe was recorded direct to computer, pre-processed, and then used as classifier input data. The correct classifier outputs were the corresponding ABPI diagnostic classification. Pulse and ABPI measurements from 100 legs were used as training data for each classifier, and the computed classifications for pulses from a further 266 legs were then compared with their ABPI diagnoses. The diagnostic accuracy of the artificial neural network (80%; was higher than for the optimized k-nearest neighbour classifier (k = 27, accuracy 76% and the linear discriminant classifier (71%). The Kappa measure of agreement which excludes chance was highest for the artificial neural network (57%) and significantly higher than that of the linear discriminant classifier (Kappa 40%, p < 0.05). The value of Kappa for the optimized k-nearest neighbour classifier (k = 27) was intermediate at 47%. This study has shown that classifiers can be taught to discriminate between small, and perhaps subtle, differences in features. We have demonstrated that artificial neural networks can be used to classify arterial pulse waveforms, and can perform better overall than k-nearest neighbour or linear discriminant classifiers for this application.

Ankle↗
PubMed1997

Ridge number density: a new parameter for in vivo bone structure analysis.

An advanced analysis of the mechanical properties of bone should include information about the microarchitecture of cancellous bone in addition to its density. It has recently been shown that high-resolution quantitative computed tomography and magnetic resonance imaging have the potential to assess such information in a noninvasive way in patients. Both techniques, however, lack sufficient spatial resolution to image the individual trabeculae with true precision. In this work, a new parameter, Ridge number density (RND), is introduced. RND is a measure for the trabecular number, which can be extracted directly from high-resolution three-dimensional (3D) images of patients. We applied the RND technique to a test group of nine healthy, postmenopausal women measured repetitively with a high-resolution 3D peripheral quantitative computed tomography (3D-pQCT) system with 165 x 165 x 165 microm3 voxel size. Simultaneously with the RND determination, the trabecular bone density (TBD) was also assessed in the same volume of interest. The examination site was the distal radius. The intersubject variability of the measured test group was 10.5% for RND and 26.3% for TBD. The root mean square error between first and second examinations (midterm reproducibility) was 1.6% and 1.1%, respectively. RND is determined independently from TBD and pertains to the structure of the cancellous bone. As such, it might add crucial information in cases where bone mass or bone density measurements alone give ambiguous results.

Bone Density↗
PubMed2000

Ultrasound and X-ray-based bone densitometry in patients with anorexia nervosa.

In 20 patients (mean age 23+/-5 years) with anorexia nervosa (AN), bone mass was evaluated by broadband ultrasound attenuation (BUA) of the calcaneus, peripheral quantitative computed tomography (pQCT) of the distal radius, and dual X-ray absorptiometry (DXA) of the lumbar spine and the hip. Compared with 20 age- and sex- matched healthy controls, patients with AN showed marked osteopenia at all measuring sites. Values of BUA (33.0+/-9 dB/MHz vs. 51.0+/-5.7 dB/MHz; P<0.0001) and of BMD of all regions of the hip (e.g., femoral neck: 0.71+/-0.13 g/cm(2) versus 0.89+/-0.07 g/cm(2); P<0.001), lumbar spine (0.82+/-0.15 g/cm(2) versus 1.24+/-0.06 g/cm(2); P<0.003) and total BMD of the peripheral radius (303.2+/-75 g/cm(3) versus 369.4+/-53.2 g/cm(3), P<0.001) were significantly reduced. Calculating a Z-score we found the most prominent differences between AN and controls by BUA of the calcaneus (-3.2+/-1.6), followed by DXA at the lumbar spine (-2.9+/-2.2) and the hip (femoral neck -2.1+/-1.7) and by pQCT at the distal radius (total BMD -1.2+/-2.0). There were highly significant correlations between BUA of the calcaneus and BMD of the femoral neck (r = 0.78, P<0.0001) and lumbar spine (r = 0.75, P<0.0001) as well as between BMD values of the femoral neck and lumbar spine (r = 0.95; P<0.0001). In addition, there were significant correlations (P<0.001) between body mass index (BMI) and the three different measuring sites and between the duration of the disease and BUA (r = 0.5, P<0.05). Our data suggest that BUA of the calcaneus is a valuable tool in the management of osteoporosis. Being a fast, radiation-free investigation method of good acceptance, it may be well suited for an assessment of the skeletal status in patients with AN.

Absorptiometry, Photon↗
PubMed2007

[Subdental synchondrosis. Computed tomographic and histologic investigation on morphological aspects of fracture at the base of the dens in 36 human axis specimens].

BACKGROUND: During development of the axis, four different ossification centers are formed. The two cranial ossification centers are demarcated from the ossification center of the vertebral corpus by a subdental synchondrosis. During further development the subdental synchondrosis--which is thought to close spontaneously--might not close completely, which leads to the necessity for differentiating synchondrotic remnants from a fracture at the base of the dens (type II according to Anderson and D'Alonzo). RESULTS: To characterize the architecture of the axis with particular attention to the subdental synchondrosis, the axis was harvested from 36 age- and gender-matched patients covering the human aging process from adolescence to senescence. In all specimens bone mineral density (BMD) was measured by peripheral quantitative computed tomography (pQCT). Morphological analysis after undecalcified processing of all specimens revealed a persistency of the subdental synchondrosis in 87% of all patients. Histological characterization of the subdental synchondrosis showed a cartilaginous structure interspersed with focal mineralization. Furthermore, static histomorphometric analysis revealed that trabecular bone volume and cortical thickness were significantly reduced within the base of the axis as compared to the dens and the corpus, respectively. CONCLUSION: Taken together, these results provide evidence that the base of the axis is a structurally distinct region. Besides well-recognized biomechanical aspects, these results suggest that the structure of the base of the axis might contribute to the occurrence of fractures of the axis and offer an additional explanation for the observation of nonunion after type II dens fractures.

Adolescent↗
PubMed1989

Computer awareness.

Computer awareness begins with recognizing the common concerns and possible fears individuals may experience upon their initial encounters with this rapidly expanding technology. Awareness is also dependent upon an individual's specific knowledge of computer hardware (including micro, mini and mainframe computers, and peripheral devices) and applications (such as information processing and information sharing). Increasing your knowledge and skills in these areas can be accomplished through various training resources. With training and experience, your overall acceptance and appreciation of computerization will continue to rise. Soon your skills will also increase, and you can then begin to experience the benefits of rapid communication and information processing.

Attitude to Computers↗
PubMedDate not supplied

Comparison of CT and catheter arteriography for evaluation of peripheral arterial disease.

Computed tomographic arteriography (CTA) has emerged as a promising technique for less invasive imaging of the lower extremity arteries. The aim of this study was to determine the concordance between CTA and catheter arteriography (CA) in patients with peripheral arterial disease (PAD). Twenty-five patients underwent both CTA and CA, and each set of images was interpreted independently by 3 readers. The infrarenal arteries were divided into 16 segments, and each segment was scored as: 1 = stenosis <50%; 2 = 50-99% stenosis; 3 = occlusion. Modal scores from 3 readers were used to compare results for each segment, with CA assumed to represent true arterial anatomy. Agreement between CTA and CA readings was defined as: concordance (modal scores were identical); moderate discrepancy (MD) (modal scores differed by 1); or severe discrepancy (SD) (modal scores differed by 2). In total, 718 segments were assessed by both CTA and CA. For all segments, the sensitivity and specificity of CTA for <50% stenosis was 86% and 90%; for 50-99% stenosis, sensitivity and specificity were 79% and 89%; and for occlusion, 85% and 98%. Above-knee (AK) CTA scores had slightly better concordance of 86.1% than below-knee (BK) readings (82.3%) (p = 0.104). Severe discrepancies between AK CTA and CA scores were observed in 1.8% of segments compared to 5.4% of BK segments (p = 0.038). Poor CTA image quality was the cause in 20% of AK segments and 28% of BK segments. Poor CA image quality was the cause in 8% of AK and 7% of BK discrepancies. Registration disagreement (stenosis observed in a level in 1 study attributed to a different level in the other) accounted for 18% of AK and 17% of BK discrepancies. In 54% of AK and 48% of BK discrepancies, neither image quality nor registration errors were identified, indicating that inherent differences in the depiction of stenosis by CA and CTA were responsible. When discrepancies caused by registration error were excluded, SD observed in BK segments (4.0%) remained significantly higher than in AK segments (1.25%) (p = 0.029), and poor CTA quality image was the most common cause (76%) of severe BK discrepancies. In AK discrepancies without an identifiable technical cause, CTA uniformly showed more stenosis, suggesting greater CTA diagnostic precision in larger vessels. In general, agreement between CTA and CA was moderately good. Compared to CA, CTA may be better at depicting stenosis in large, proximal vessels owing to the superior accuracy of cross-sectional images in the measurement of stenosis. There appeared to be poorer CT resolution and higher frequency of severe discrepancies between CTA and CA in BK arteries.

Age Factors↗
PubMed1998

Assessment of bone mineral at appendicular sites in females with fractures of the proximal femur.

The prediction of hip fractures by measurements at remote sites or the improvement of predictive power by measurements at multiple sites could potentially increase the success of osteoporosis screening programs. In a cross-sectional study on 137 postmenopausal women, we tested the hypothesis that bone assessment at the hip, the forearm, and the tibia are independently associated with osteoporotic fractures of the hip. Bone mineral densities, geometric features, and ultrasound properties were determined with hip dual X-ray absorptiometry, forearm peripheral quantitative computed tomography (QCT), and tibia speed of sound measurement. While the odds ratios for fracture discrimination per standard deviation decrease ranged between 3 and 4 for measurements at the hip, they were only 1.8 at the forearm and 1.4 at the tibia. Measurements at the tibia or the forearm were neither independently associated with osteoporotic hip fractures (p > 0.05) nor could any combination of measurements significantly increase the power for the identification of fractures as measured with receiver operating curves. Women who sustained trochanteric fractures were characterized by a generalized loss of bone mineral. Cervical fractures were associated with a decrease of bone mineral density at the hip, but no significant alterations in bone mass or geometric properties were observed at the tibia or at the forearm. Fracture risk prediction at the hip is therefore preferably performed by measurements at the hip itself. Peripheral QCT at the distal radius and tibial ultrasound seem capable of depicting women with an increased risk for trochanteric but not for cervical fractures. The risk assessment appears not to be improved by including information of cortical or geometric properties of the forearm.

Absorptiometry, Photon↗
PubMed2001

Ultrasound velocity and cortical bone characteristics in vivo.

Axial transmission of ultrasound along cortical bone may reflect a combination of material and structural properties of long bone cortices. The goal of this study was to determine the association of speed of sound (SOS) with cortical density (CoD), cortical wall thickness (CWT), and total cortical area (CoA). Quantitative ultrasound (QUS) and peripheral quantitative computed tomography (pQCT) were used to measure the above variables in the distal third of radius and the midshaft of tibia in 51 postmenopausal women aged 62 to 71 years. Univariate regression analysis showed that the site-specific CoD accounted for 34% of the variability in the radial SOS and 29% of that in the tibial SOS (p < 0.001 both). SOS was only moderately associated with radial CWT (R2 = 0.14, p < 0.05) and CoA (R2 = 0.12, p < 0.05), but not with tibial CWT nor CoA. After controlling for CoD, these dimension-related associations disappeared. Stepwise multiple regression analysis showed that CoD was the only significant determinant of radial SOS (adjusted R2 = 0.31), whereas for tibia, not only CoD but also the years since menopause were associated with SOS (adjusted R2 = 0.41). In conclusion, out of the studied macroscopic cortical variables, CoD (an apparent surrogate for material properties of bone) was the only determinant of SOS measured in vivo at radial and tibial shafts. The key question that still needs to be answered is whether the SOS information obtained from the peripheral long bone cortical shafts can be translated to describe the mechanical competence and quality of clinically pertinent bones (e.g. proximal femur) of a given individual.

Aged↗
PubMed1996

Criteria for the evaluation of treatment planning systems.

Radiation treatment planning systems (RTPS) are evolving on a rapid and continual basis. After the evaluation of several commercial systems, we have developed a list of features we consider desirable in a product. The goal in the compilation of these criteria was a comprehensive worksheet which categorized the characteristics of RTPS into hardware (computer and peripheral devices), 2-D planning tools, 3-D planning tools, irregular field planning tools, and brachytherapy planning. With these distinctions, one can evaluate a system conforming to the specific planning needs, e.g., conformal therapy, dynamic therapy capabilities, or optimized remote afterloading brachytherapy, of a department. The rationales of the special requirements are provided for justification.

Brachytherapy↗
PubMed1992

Eight year's experience with automated anesthesia record keeping: lessons learned--new directions taken.

For the past eight years, an automated anesthesia record keeping system, COMANDAS (COMputerized ANesthesia Data Acquisition System) has been used in the cardiovascular operating rooms at Mayo Clinic. The automated anesthesia record is designed to match the traditional hand-written record and becomes part of the official medical record. COMANDAS is interfaced with the physiologic monitor and mass spectrometer in each OR, and a number of other computers within the Mayo Medical Center. Since the introduction of COMANDAS over 24,000 surgical procedures have been charted. The anesthesia record is more complete, consistent in organization, and legible when compared to a hand-written record. Recently, it was determined that the computers and peripherals that make up COMANDAS were wearing out and that the vendors would no longer support or replace the equipment. A process to find a replacement for COMANDAS was then begun. Although the cardiovascular anesthesia group was satisfied with the automated anesthesia record, there were a number of areas in which improvement was desired. A systematic evaluation of the system was begun with a survey of the users. The majority of those surveyed felt that COMANDAS was a useful system which made parts of their job easier. The user interface, method of manual data entry, time to produce the record and difficulty learning the system were the source of the greatest dissatisfaction. Artifacts, networking, interfacing with other devices and computers were also issues for the replacement system. Most commercial systems were found wanting in one or more areas of significance. The most practical solution appeared to be the modification of a currently available intensive care unit patient data management system.

Anesthesiology↗
PubMed2006

Bone loss from the human distal tibia epiphysis during 24 days of unilateral lower limb suspension.

Bone loss during immobilization is well documented. Currently, the only means of studying this in human beings is bed rest, which is resource intensive and inconvenient for the subjects. Unilateral lower limb suspension (ULLS) has been suggested as an alternative, but has not previously been demonstrated to cause bone loss. The main aim of our study was to test the hypothesis that ULLS would cause bone loss determined by peripheral quantitative computed tomography (pQCT). We investigated eight young healthy volunteers (19.1 +/- 0.7 years; body mass index, 22.4 +/- 2.6 kg m(-2)), who underwent ULLS for 24 days; their right foot was suspended with a strap attached to the shoulder so the knee angle was 10 deg and they wore a left shoe with a 7.5 cm sole to allow clearance of the right foot and used bilateral crutches to perambulate. Bone scans were obtained by pQCT from the distal epiphyses and from the diaphyses of the tibia in each leg twice before suspension, at days 7, 14 and 21 of the ULLS, and at days 4, 9, 35 and 90 of recovery. After 21 days of ULLS, bone mineral content of the peripheral portion of the epiphysis of the suspended tibia was reduced by 0.89 +/- 0.48% (from 280.9 +/- 34.5 to 278.4 +/- 34.2 mg mm(-1), P < 0.001) but no changes were observed in its central portion or in the unsuspended tibia. In the peripheral epiphyseal portion, significant bone loss (by 0.32 +/- 0.54%, P = 0.045) occurred as early as day 7 of ULLS. We have demonstrated, for the first time, that in humans bone is lost during ULLS at rates comparable to those seen with bed rest, without alteration in limb fluid volumes thus validating the technique and raising important questions about the mechanisms involved.

Adult↗
PubMed2003

Smaller and faster: using a handheld computer to support a bedside vascular access team.

An application for a handheld computer was developed to support the Vascular Access team in an academic medical center. The development involved workflow analysis and usability testing centered on the users. The application interfaced with the desktop to generate the documentation needed for the charts and to populate the database used to track productivity, volume, outcomes, etc. Post-implementation evaluations provided feedback to validate the utility of the system to support workflow of the team.

Catheterization, Central Venous↗
PubMed2005

Relationship between masticatory function and internal structure of the mandible based on computed tomography findings.

INTRODUCTION: The purposes of this study were to investigate bone mineral density as a part of bone construction in human skulls and to examine the relationship between dentofacial morphology and masticatory function by using computed tomography (CT) findings. Changes in bone mineral density in the mandible because of loss of masticatory function were tested in rats by experimentally producing an environment that inhibited mastication by the molars. METHODS: Data for the human study were obtained from 27 modern male Japanese skulls (mean age, 28 years) from the University of Tokyo. Cortical bone thickness (CBT) and CT value (CV) were measured by each CT scan of the first and molars. For the animal study, a metal cap was inserted between the maxillary and mandibular incisors to prevent the molars from biting in 6-week-old male Wistar rats. The rats were killed after 2, 4, or 6 weeks, and bone mineral density was measured in cancellous and cortical bone equivalent to the first molar region by using peripheral quantitative computed tomography. RESULTS: In the human skull study, significant negative correlations were observed between CV in the regions of the buccal side of the second molar and the angle between the Frankfort horizontal and mandibular planes. Significant negative correlations were also observed between the gonial angle and CV in the buccal and basal sides. In the animal study, cancellous bone mineral density began to decline 4 weeks after the start of the experiment in the masticatory hypofunction group compared with the control group. By week 6, cancellous bone density had declined by 11.6% on the buccal side, 16.7% on the lingual side, 12.3% at the bifurcation of the root, and 38.1% at the root apex. Cortical bone density declined by 8% to 12% on the lingual side. CONCLUSIONS: The results support our hypothesis that a functional adaptive response by the mandible to mechanical stress resulting from mastication occurs not only in the muscle insertion area, but also in mandibular alveolar bone in the molar region.

Adaptation, Physiological↗
PubMed1988

Granulomatous hepatitis associated with cat scratch disease.

In three patients with cat scratch disease the liver was affected. All three had high fever (39 degrees C) for more than 3 weeks. Two of them had no peripheral adenopathy. Computed tomography of the abdomen revealed focal hepatic defects in two patients and periportal and periaortic adenopathy in the third. At laparotomy, there were nodules on the liver surfaces of all patients and histological examination revealed necrotising granulomata. The Warthin-Starry silver stain showed organisms consistent in appearance with the cat scratch bacillus in the liver and a periaortic lymph node of one patient, in the liver of the second patient, and in the axillary lymph node of the third. In all three patients the clinical findings and radiological abnormalities improved without specific therapy. A review of the surgical pathology files of Washington University revealed only two other cases of granulomatous hepatitis in children over a 6-year period. These findings indicate that cat scratch disease should now be included in the differential diagnosis of granulomatous hepatitis, at least in children. The absence of peripheral adenopathy in two of the three patients with granulomatous hepatitis suggests that the clinical spectrum of cat scratch disease may be broader than previously appreciated.

Cat-Scratch Disease↗
PubMed2002

Cross-sectional and longitudinal study of osteoporosis in patients with rheumatoid arthritis.

To elucidate the pathology of osteoporosis associated with rheumatoid arthritis (RA), bone mass measurements were performed in 146 female patients with RA and compared with those in 150 age-matched female patients with osteoarthritis (OA) and postmenopausal osteoporosis (OP). Bone mineral density (BMD) was measured at the lumbar spine (L-BMD), the mid-radius (MR-BMD) and the calcaneus (C-BMD) by dual-energy X-ray absorptiometry (DXA), and at the distal radius by peripheral quantitative computed tomography (pQCT). The RA group showed significantly lower BMD at all sites, except L-BMD, than the OA group. Compared with the OP group, the RA group showed a significantly higher L-BMD but no difference at other sites. BMD in RA decreased with disease severity at all sites and lean body mass was highly correlated with L-BMD and C-BMD. Cross-sectional analysis revealed early bone loss at the distal radius and a decrease of L-BMD, MR-BMD, and C-BMD with disease duration. Longitudinal analysis showed that the annual loss of L-BMD, MR-BMD and C-BMD tended to be lower with increasing disease duration. Glucocorticoid administration had no influence on L-BMD, MR-BMD or C-BMD. We concluded that, unlike postmenopausal osteoporosis, osteoporosis associated with RA is characterised by relatively preserved bone mass in the axial bone and marked loss in the peripheral bone. The risk factors for generalised osteoporosis are a long disease duration, severity of disease, and decreased lean body mass.

Absorptiometry, Photon↗