MR appearances of the locked knee

This review illustrates the MR appearances of commonly encountered problems that can present as a "locked knee", as well as several unusual causes. Internal derangement of menisci, particularly bucket handle tears, predominate. Loose bodies as a result of trauma/degeneration and lesions such as cysts of the cruciate ligaments and focal pigmented villonodular synovitis are also illustrated. While meniscal tears are the major cause of "locked knee" in clinical practice, interference with normal knee kinematics is non-specific with regard to the diagnosis. Emphasis is therefore given to less frequently seen abnormalities that lead to a mechanical block of knee extension.

Reactive synovitis of the knee joint: MR imaging appearance with arthroscopic correlation

OBJECTIVE

To evaluate the use of routine MR imaging sequences in detecting and characterizing secondary reactive synovitis of the knee joint using arthroscopy as the standard of reference.

DESIGN AND PATIENTS

Fifty consecutive patients with a history of knee pain who were referred for MR imaging and subsequently underwent arthroscopy of the knee comprised the study group. MR images were evaluated for the presence and appearance of synovitis reflected in synovial thickening and irregularity. Synovial thickening was graded on MR imaging as follows: 0=normal, 1=thin line of increased signal intensity, 2=increased signal intensity with frond-like or hair-like projections and a granular appearance of joint fluid. Standard knee imaging protocols were used.

RESULTS

The sensitivity, specificity, and accuracy of MR imaging in detecting synovitis compared with arthroscopy were 88%, 97%, and 95%, respectively. Grade 1 synovitis was best seen on proton-density-weighted images, demonstrating increased signal intensity of the synovium against the relatively low signal intensity of the joint fluid. Grade 2 synovitis was best seen on proton-density images and T2-weighted spin echo and fast spin echo images with fat saturation, demonstrating a granular and linear hair-like appearance of joint fluid. Axial and sagittal imaging planes were most helpful in the diagnosis of synovitis.

CONCLUSION

Routine MR pulse sequences are useful in identifying the presence and extent of synovial abnormalities. The detection of different stages of synovial pathology should become an important part of the evaluation of the post-traumatic patient as treatment may be altered as a result.

Vertebral fracture prevalence among women screened for the Fracture Intervention Trial and a simple clinical tool to screen for undiagnosed vertebral fractures. Fracture Intervention Trial Research Group

OBJECTIVE

To evaluate the ability of self-reported risk factors to identify postmenopausal women likely to have extant vertebral fractures because approximately two thirds of women with radiographic evidence of vertebral fracture are unaware of the fracture.

PATIENTS AND METHODS

Questionnaire and spinal radiographic data were collected from postmenopausal women with a femoral neck bone mineral density T score of -1.6 or lower during screening for the Fracture Intervention Trial. Logistic regression was used to identify risk factors for extant vertebral fractures and to derive a final multivariable model.

RESULTS

Almost two thirds of 25,816 women 55 years and older met the bone density criterion, and 21% of those had an extant vertebral fracture. The final model consisted of 5 self-reported items: history of vertebral fracture, history of nonvertebral fracture, age, height loss, and diagnosis of osteoporosis. These were combined to yield a Prevalent Vertebral Fracture Index (PVFI). The prevalence of women with vertebral fracture varied from 3.8% to 62.3% over the range PVFI of 0 to greater than 5. Among the 13,051 women screened with spinal radiographs, a PVFI of 4 or greater identified 65.5% of women with vertebral fractures (sensitivity), with a specificity of 68.6%. Excluding 881 women who reported prior vertebral fractures reduced the sensitivity to 53.6 % and increased the specificity to 70.7% but did not alter the fracture prevalence at PVFI values less than 6.

CONCLUSION

In this population, 5 simple questions identified women who were likely to have undiagnosed vertebral fractures. Further research is needed to determine the validity of this index in other populations, including women without low bone mineral density.

Micro CT and Micro MR imaging of 3D architecture of animal skeleton

Quantitative assessment of three-dimensional (3D) trabecular structural characteristics may improve our ability to understand the pathophysiology of osteoporosis, to test the efficacy of pharmaceutical intervention, and to estimate bone biomechanical properties. Considerable progress has been made in advanced imaging techniques for noninvasive and/or nondestructive assessment of 3D trabecular structure and connectivity. Micro computed tomography (microCT) has been used to measure 3D trabecular bone structure in rats, both in vivo and in vitro. It can directly quantify 3D trabecular bone structure such as trabecular volume, trabecular thickness, number, separation, structure model index, degree of anisotropy, and connectivity, in a model-independent manner. We have used microCT to study ovariectomy (OVX) induced osteopenia in rats and its treatment with agents such as estrogen, and sodium fluoride. We have demonstrated that 3D microCT can quantify mouse trabecular and cortical bone structure with an isotropic resolution of 9 microm(3). It is also useful for studying osteoporosis in mice and in phenotypes of transgenic mice or gene knockout mice. MicroCT can be used to quantify osteogenesis in mouse Ilizarov leg lengthening procedures, to quantify osteoconduction in a rat cranial defect model, and to quantify cortical bone porosity. Recently, microCT using high intensity and tight collimation synchrotron radiation to achieve spatial resolution of 1-2 microm has provided the capability to assess additional features such as resorption cavities. Unlike microCT, micro magnetic resonance imaging (IMRI) is nonionizing. Recently, the ability of microMRI to assess osteoporosis in animal models has been explored. Using a small, high-efficiency coil in a high-field imager, microMRI can give resolutions sufficient to discriminate individual trabeculae. We have shown that, with appropriate settings, it is possible to image trabecular bone in rats in vivo and in vitro. In our study of OVX rats, analysis of microMR images can demonstrate differences in rat trabecular bone that are not detected by DXA measurements. In a rabbit OA model, with the OA induced by meniscectomy or anterior cruciate ligament transection, MRI shows decreased cartilage thickness, subchondral osteosclerosis and osteophytes, while radiographs can only show subchondral osteosclerosis and osteophytes could not be found. Advanced imaging methods are able to measure 3D trabecular structure and connectivity in arbitrary orientations in a highly automated, objective, non-user-specific manner, allowing greater numbers of samples for unbiased comparisons between controls and the disordered or treated. They can be utilized on a large sample leading to fewer sampling errors. They are non-destructive allowing multiple tests such as biomechanical testing and chemical analysis on the same sample; and non-invasive permitting longitudinal studies and reducing the number of animals needed.

Evaluation of a new body composition phantom for quality control and cross-calibration of DXA devices

This study evaluated a new body composition phantom and its use for quality control and cross-calibration of dual-energy X-ray absorptiometry (DXA) instruments for measurements of body composition. We imaged the variable composition phantom (Lunar, Madison, WI) on eight different DXA devices. Deviations of up to 7% fat were observed when we compared the percent fat values measured by the different devices with the nominal values provided by the manufacturer. Absolute precision error of percent fat measurements for the phantom ranged from 0.6 to 0.8%. The phantom's percent fat values were also compared with whole body composition measurements from 130 female and male volunteers. The phantom detected differences in percent fat values that were similar to those found by comparing in vivo measurements with values from different DXA scanner models from the same manufacturer. When comparing different models of scanners from different manufacturers, such as the Hologic QDR-4500 and the Lunar DPX-IQ, the phantom showed a different relationship than was seen for patients. Therefore, corrections or comparisons based on the phantom data alone would be incorrect. In conclusion, the Lunar variable composition phantom is capable of accurately measuring the fat calibration of DXA devices and may be suitable for cross-sectional cross-calibration between scanners from the same manufacturer; however, for comparison of DXA scanners from different manufacturers, in vivo cross-calibration is still the only accurate method. The phantom may be used in longitudinal quality control to verify an instrument's temporal stability.

Evaluation of a new body composition phantom for quality control and cross-calibration of DXA devices

This study evaluated a new body composition phantom and its use for quality control and cross-calibration of dual-energy X-ray absorptiometry (DXA) instruments for measurements of body composition. We imaged the variable composition phantom (Lunar, Madison, WI) on eight different DXA devices. Deviations of up to 7% fat were observed when we compared the percent fat values measured by the different devices with the nominal values provided by the manufacturer. Absolute precision error of percent fat measurements for the phantom ranged from 0.6 to 0.8%. The phantom's percent fat values were also compared with whole body composition measurements from 130 female and male volunteers. The phantom detected differences in percent fat values that were similar to those found by comparing in vivo measurements with values from different DXA scanner models from the same manufacturer. When comparing different models of scanners from different manufacturers, such as the Hologic QDR-4500 and the Lunar DPX-IQ, the phantom showed a different relationship than was seen for patients. Therefore, corrections or comparisons based on the phantom data alone would be incorrect. In conclusion, the Lunar variable composition phantom is capable of accurately measuring the fat calibration of DXA devices and may be suitable for cross-sectional cross-calibration between scanners from the same manufacturer; however, for comparison of DXA scanners from different manufacturers, in vivo cross-calibration is still the only accurate method. The phantom may be used in longitudinal quality control to verify an instrument's temporal stability.

Progression of radiographic joint erosion during low dose corticosteroid treatment of rheumatoid arthritis

OBJECTIVE

The reported prevention of joint damage during treatment with prednisolone 7.5 mg daily in patients with early rheumatoid arthritis (RA)3 may have important implications for management of RA. We evaluated this observation in another patient population.

METHODS

Radiographic progression rates in paired hand radiographs were analyzed in 824 patients with RA who participated in a 3 year prospective, randomized clinical trial comparing the nonsteroidal antiinflammatory drugs (NSAID) etodolac (150 or 500 mg bid) and ibuprofen (600 mg qid). Disease modifying antirheumatic drugs (DMARD) were not permitted. Prednisone < or=5 mg daily was continued by 197 patients (mean dose 4.37 mg daily) who had started prednisone therapy at least 6 mo before study entry, but new prednisone starts were not allowed. Standardized hand/wrist radiographs were done yearly and at dropout; joint erosion and narrowing scores of 3 readers were averaged and progression rates were compared.

RESULTS

Mean duration of RA was 3.6 years (range 1-7); patients' ages were 21-78 years; 71% were women. Among the 824 patients, those taking prednisone were more likely to have had previous DMARD, and at study entry had higher radiographic scores for joint erosion and joint space narrowing and slightly higher swollen joint counts, C-reactive protein values, and rheumatoid factor titers than those not taking prednisone. However, for the subgroup of 252 patients with RA duration of 12-24 months, prestudy radiographic scores were not different in those taking or not taking prednisone. The mean (+/-SD) monthly rate of increase in erosion scores was 0.228 +/-0.37 for the prednisone patients and 0.206+/-0.35 for patients not taking prednisone (p = 0.994 by ANCOVA). The subgroup with 12 to 24 months' disease duration at entry also showed no significant effect of prednisone treatment on erosion progression.

CONCLUSION

Clinically indicated low dose prednisone did not prevent progressive radiographic damage in 197 NSAID treated patients whose physicians had initiated < or =5 mg daily before study entry. The risk/benefit ratio of chronic low dose prednisone in early RA remains uncertain.

Dedicated extremity MR imaging of the foot and ankle

The purpose of this review is to provide illustrative examples of diseases of the foot and ankle when imaged with a low-field MR imaging system. A retrospective review of 268 foot and ankle examinations, performed in our institution within the past 3 years with a 0.2-T (Artoscan Esaote, Genoa, Italy) dedicated extremity MR system was done. Additionally, illustrative comparison with conventional radiography and high-field MR imaging is presented in patients in whom these examinations were also performed. Although motion artifact limited the value of a few studies, in the majority of examinations low-field MR imaging provided diagnostic image quality for the full spectrum of disorders affecting the foot and ankle and seemed to be a feasible alternative to high-field MR imaging in establishing an accurate diagnosis.

Prediction of bone strength of distal forearm using radius bone mineral density and phalangeal speed of sound

This investigation compares quantitative ultrasound (QUS) measurement of the phalanges with peripheral quantitative computed tomography (pQCT) and dual X-ray absorptiometry (DXA) measurement of the forearm, to estimate the strength of the distal radius in 13 cadaveric forearms. The cadavers were scanned at the distal radius by pQCT and DXA for bone mineral density (BMD) and at the approximate phalanges by QUS for speed of sound (SOS). The distal radii were subjected to a simulated Colles fracture produced with a materials testing machine. The load at which the distal radius was fractured was considered as a representation of bone strength. The bone strength correlated significantly with SOS at different phalanges (r = 0.63-0.72), BMD at different regions of interest by DXA (r = 0.67-0.75), and cortical BMD at different sites by pQCT (r = 0.61-0.67). Standard stepwise regression analysis showed that adding phalangeal SOS into forearm densitometric variables significantly enhanced the statistical power for prediction of the strength of the distal radius. Our results suggest that, for assessment of site-specific distal forearm strength, QUS measurement of the phalanges is comparable to forearm densitometry. Phalangeal QUS may add clinical value if distal forearm strength has a high priority.

Magnetic resonance arthrography in children with developmental hip dysplasia

Conventional and gadolinium enhanced magnetic resonance arthrograms were done on 14 hips in 10 children ages 7 to 24 months. The contralateral normal hips in those with unilateral disease were studied with unenhanced magnetic resonance imaging for comparison. By conventional arthrography, there were no well visualized structures. Visualized structures seen as filling defects were the labrum, ligamentum teres, and transverse acetabular ligament. By magnetic resonance arthrography, well visualized structures were the labrum, ligamentum teres, transverse acetabular ligament, and pulvinar. By unenhanced magnetic resonance imaging, well visualized structures were the labrum, ligamentum teres, and transverse acetabular ligament. The difference in visualization by magnetic resonance arthrography versus conventional arthrography was statistically significant with respect to all five structures: labrum, ligamentum teres, transverse acetabular ligament, pulvinar, and psoas tendon. The difference in visualization by magnetic resonance arthrography versus unenhanced magnetic resonance imaging was statistically significant with respect to the labrum and pulvinar. Magnetic resonance arthrography is indicated for assessing complete concentric reduction when it does not appear to be achieved by conventional arthrography, for confirming closed reduction immediately after manipulation, and potentially for preoperative planning for an open reduction.

Neural network based algorithm to quantify joint space width in joints of the hand for arthritis assessment

Arthritis diseases are widespread with enormous societal costs. The two most common forms, rheumatoid arthritis and osteoarthritis, affect joints of the hand and cause narrowing of the joint spaces as the disease destroys the articular cartilage. Radiographic assessment is one of the most promising tools to detect subtle changes in joint space width (JSW), and therefore disease progression. Currently radiographic assessment of arthritis in joints of the hand is accomplished though semiquantitative subjective scoring systems which do not provide a quantitative measurement of the JSW. We describe here an automated method which calculates the average JSW of the metacarpophalangeal (MCP), proximal interphalangeal (PIP), and distal interphalangeal (DIP) joint spaces for fingers 2 to 5 (index, middle, ring, and little) on digitized hand radiographs. The method was tested with a set of 54 hand radiographs on joints with mild to moderate rheumatoid arthritis. Performance was evaluated by comparing algorithm measured JSW to a gold standard determined from expertly hand-drawn joint margins. The agreement was quantified by a measurement of root mean square deviation, 0.148 mm, 0.089 mm, and 0.114 mm for the MCP, PIP, and DIP joints, respectively. In addition, the algorithm measured JSW strongly correlated with the gold standard: R2=0.80 (MCP), R2= 0.82 (PIP), and R2= 0.84 (DIP). This is an accurate and robust algorithm and should provide a more quantitative measure of disease progression than current methods.

A multicenter, double-blind, dose-ranging, randomized, placebo-controlled study of recombinant human interleukin-1 receptor antagonist in patients with rheumatoid arthritis: radiologic progression and correlation of Genant and Larsen scores

OBJECTIVE

To evaluate radiographic progression and the relationship of radiologic scores obtained by the Genant and Larsen methods in a clinical trial of recombinant human interleukin-1 receptor antagonist (IL-1Ra).

METHODS

Patients with rheumatoid arthritis (RA) were randomized into 4 groups: placebo (n = 121) or IL-1Ra at a daily dosage of 30 mg (n = 119), 75 mg (n = 116), or 150 mg (n = 116). Hand radiographs obtained at baseline, 24 weeks, and 48 weeks were scored using both methods.

RESULTS

At 24 weeks, by the Genant method, there was significant reduction in the score for progression of joint space narrowing (JSN) and the total score (a combination of erosion and JSN) in all treatment groups. Least-squares mean changes in the Genant erosion score from baseline to 24 weeks were significantly reduced after treatment with IL-1Ra at 30 mg/day and for all IL-1Ra treatment groups combined. The changes corresponded to a reduction of 38% in erosion, 58% in JSN, and 47% in total score. Patients treated with IL-1Ra at 75 mg/day had a significant reduction in the Larsen erosive joint count (LEJC), and all IL-1RA-treated groups combined showed a 45% reduction. Correlations (r) between the Genant total and Larsen scores were 0.84 at baseline, 0.83 at week 24, and 0.83 at week 48 (P < 0.0001); correlations between the Genant erosion score and the LEJC were 0.83 (P < 0.0001) at all visits; correlations between the Genant total and the Larsen scores were 0.32 and 0.49 (P < 0.0001) for progression from baseline to week 24 and from baseline to week 48, respectively; correlations between the Genant erosion score and the LEJC were 0.36 and 0.41 (P < 0.0001) for progression to weeks 24 and 48, respectively.

CONCLUSION

IL-1Ra reduced radiologic progression of RA. Scores by the 2 methods correlated strongly for each individual time point, but much less strongly for assessments of disease progression.

Bone mass continues to increase at the hip after parathyroid hormone treatment is discontinued in glucocorticoid-induced osteoporosis: results of a randomized controlled clinical trial

Glucocorticoid-induced osteoporosis is the most common secondary cause of osteoporosis. In this 24-month study, we report changes in bone turnover and bone mass after 12 months of daily injections of human parathyroid hormone 1-34 [hPTH(1-34)] and 12 months off treatment in postmenopausal women (mean age, 63 years) with osteoporosis treated with glucocorticoid and hormone replacement therapy. Response to the treatment was assessed with bone mineral density (BMD) measurements of the lumbar spine by quantitative computed tomography (QCT); BMD measurements of the lumbar spine, hip, and forearm by dual-energy X-ray absorptiometry (DXA); and biochemical markers of bone turnover. The mean (+/-SEM) change in BMD of the lumbar spine by QCT and DXA in the PTH group at 24 months was 45.9+/-6.4% and 12.6+/-2.2% (p < 0.001). The change in total hip and femoral neck BMD was not significant at 12 months but increased to 4.7+/-0.9% (p < 0.01) and 5.2+/-1.3% at 24 months, respectively, as compared with a relatively small change of 1.3+/-0.9% and 2.6+/-1.7% in the estrogen-only group. The mean percent differences in BMD of the lumbar spine by QCT and DXA between the groups at 24 months were 43.1% and 11.9%, respectively (p < 0.001). The mean percent differences over the estrogen-only group in hip BMD were 3.4% for total hip (p < 0.01) and 2.6% for femoral neck at 24 months. Biochemical markers of bone turnover increased to more than 150% during the first 6 months of therapy, remained elevated throughout the 12-month treatment period, and returned to baseline values within 6 months of discontinuing the PTH treatment. These results suggest that PTH dramatically increases bone mass in the lumbar spine and hip in postmenopausal women with glucocorticoid-induced osteoporosis who are taking hormone replacement therapy. However, the maximum effect of this anabolic agent on bone mass at the hip after 12 months of treatment requires at least 6-12 months after the PTH treatment is discontinued.

MR anatomy of the subcoracoid bursa and the association of subcoracoid effusion with tears of the anterior rotator cuff and the rotator interval

OBJECTIVE

We describe the MR anatomy of the subcoracoid bursa and findings associated with subcoracoid effusion.

CONCLUSION

Fluid in the subcoracoid space, revealed on MR imaging of the shoulder, may lie in the subcoracoid bursa or the subscapularis recess (both structures can be distinguished with MR imaging). In our patients, subcoracoid effusions were often associated with anterior rotator cuff tears, including tears of the rotator interval.

Association of intramuscular cysts of the rotator cuff with tears of the rotator cuff: magnetic resonance imaging findings and clinical significance

Cystic lesions that arise adjacent to the shoulder have been reported in association with labral tears or as an unusual manifestation of massive rotator cuff tears. The purpose of this study was to define the relationship between intramuscular cysts of the rotator cuff and tears of the rotator cuff. Thirteen cases of intramuscular cysts of the rotator cuff were identified on magnetic resonance imaging of the shoulder and analyzed retrospectively along with the clinical data. Surgical findings were retrospectively reviewed in 5 patients who underwent follow-up arthroscopy. This series shows that intramuscular cysts of the rotator cuff are associated with small, full-thickness tears or partial undersurface tears of the rotator cuff. These cysts are easily identified on T2-weighted sequences and, when present, should always prompt a thorough search for associated rotator cuff pathology.

Morphometric X-ray absorptiometry and morphometric radiography of the spine: a comparison of prevalent vertebral deformity identification

Prevalent vertebral deformities are associated with a substantially increased risk of subsequent vertebral and nonvertebral fractures. Knowledge of vertebral fracture status is an important component in the prediction of further fractures in patients with osteoporosis. This study reports a comparison of the quantitative identification of vertebral deformities on morphometric X-ray absorptiometry (MXA) scans and conventional radiographs (MRX) in 161 postmenopausal women (mean age +/- SD, 64 +/- 7.1 years) recruited from patients referred by their family doctor for bone density measurement (n = 119) and osteoporotic subjects with known vertebral deformities attending an osteoporosis clinic (n = 42). Each subject had MXA scans and MRXs of the thoracolumbar spine, to image the vertebrae from T4-L4, at a single visit. The scans and radiographs were analyzed by two trained observers using six points to quantify the shape of each vertebral body. From these points, three vertebral heights were measured: anterior, middle, and posterior. Vertebral deformities were identified using the algorithms proposed by Eastell and by McCloskey. Generally good to excellent agreement (per vertebra, kappa = 0.87-0.93; per subject, kappa = 0.81-0.91) was observed between the two algorithms used for quantitative vertebral deformity identification using MXA or MRX. More moderate agreement (per vertebra, kappa = 0.70-0.79; per subject, kappa = 0.67-0.75) was seen when comparing the same algorithm between MXA and MRX. Agreement between MXA and MRX for the McCloskey algorithm was better than for the Eastell algorithm, largely because of the lower number of false positives produced by the McCloskey methodology. Deformity identification by MXA was limited because of poor image quality, primarily in the upper thoracic spine. One in six MRX deformities were missed by MXA as they occurred in vertebrae not visualized sufficiently for analysis on the MXA scans. Deformity identification was poorer in the upper thoracic spine in analyzable vertebrae with a sensitivity of 50.0% for MXA in terms of MRX using the Eastell algorithm for the vertebral levels T4-T7, compared with 80.6% for L1-L4A. MXA proved to be more effective at identifying moderate to severe MRX deformities producing a sensitivity of 22.0% for MXA in terms of identifying MRX grade 1 deformities using the Eastell algorithm, compared with 81.6% for grade 2 deformities. Although MXA image quality is inferior to that of conventional radiographs, MXA has distinct advantages such as a substantially reduced effective dose to the patient and acquisition of a single image of the spine. MXA is a potentially useful, relatively fast, low-radiation technique to identify prevalent vertebral deformities, particularly moderate to severe deformities in the middle/lower thoracic and lumbar spine, in conjunction with morphometric radiography in some patients.

Trainable rule-based algorithm for the measurement of joint space width in digital radiographic images of the knee

The progression of osteoarthritis (OA) can be monitored by measuring the minimum joint space width (mJSW) between the edges of the femoral condyle and the tibial plateau on radiographs of the knee. This is generally performed by a trained physician using a graduated magnifying lens and is prone to the subjectivity and variation associated with observer measurement. We have developed software that performs this measurement automatically on digitized radiographs. The test data consisted of 180 digitized radiographs of the knee (90 duplicate acquisitions) from 18 normal (nonarthritic) subjects and 38 images from 10 subjects with OA. These were digitized and manually cropped so that the images were free of nonanatomical structures and the knee was approximately centered. The software first determined the edge of the femoral condyle on 400 microm pixel subsampled images. Contours marking the location of the tibial plateau in the medial compartment were found on 100 microm images using the femoral edge as a reference. The algorithm was trained using an independent but similar data set and using a jackknife approach with the test data. The results were compared to contours drawn by a trained reader and the duplicate acquisitions were used to measure the reproducibility of the mJSW measurement. The reproducibility was 0.16 mm and 0.18 mm for normal and osteoarthritic knees, respectively, representing an improvement of approximately a factor of 2 over manual measurement. The algorithm also showed excellent agreement with the hand-drawn contours and with mJSW determined by the manual method.

Short-term increases in bone turnover markers predict parathyroid hormone-induced spinal bone mineral density gains in postmenopausal women with glucocorticoid-induced osteoporosis

The purpose of this study was to test the ability of early changes in markers of bone turnover to predict subsequent changes in bone mineral density (BMD) induced by parathyroid hormone fragment, PTH (1-34), in postmenopausal osteoporotic women treated with estrogen and glucocorticoids. Forty-nine postmenopausal women with chronic, inflammatory diseases and BMD T-scores < or = -2.5 at the lumbar spine or femoral neck who were concurrently treated with estrogen > or = 1 year and prednisone 5-20 mg/day for > or = 1 year participated. Subjects were randomized to treatment with human PTH (1-34) 400 IU/day or to a control group for 1 year and followed for an additional year. Serum and urine were collected at baseline and 1, 3, 6, 9, 12, 18 and 24 months for measurement of bone alkaline phosphatase (BAP), osteocalcin (OC) and deoxypyridinoline (DPD). We constructed an Uncoupling Index (UI) from all three markers (UI = [ZBAP + Zoc]/2 -ZDPD, where the Z-score for each marker in each subject was calculated from the mean and standard deviation of the study population at baseline). BMD of the lumbar spine and hip was measured at baseline and every 6 months thereafter by dual-energy X-ray absorptiometry (DXA) and annually by quantitative computed tomography (QCT; spine only). BMD of the spine, but not hip (total, femoral neck or trochanter), and levels of all three markers increased significantly as a result of PTH treatment (p<0.01 compared with controls). The resorption response lagged behind that of formation as evidenced by a significant increase (p < 0.05) in the UI for the first 9 months of treatment. The UI values and changes from baseline to 1, 3 and 6 months in BAP, OC and DPD were correlated with the 12- and 24-month changes in spine BMD measured both with QCT and with DXA (Spearman's rank coefficients <0.76; p<0.05). Most PTH-treated subjects could be identified as biochemical responders by least significant change analysis. Following 1 month of therapy, BAP and OC identified 65% and 81% as responders, respectively. The responder rates were 79%, 79% and 75% for BAP, OC and DPD, respectively by 6 months. Responders exhibited a high level of diagnostic accuracy for predicting a gain in BMD (areas under the receiver operating characteristic curves exceeding 0.79 for QCT and 0.70 for DXA), but not the magnitude of the gain. These data suggest that serial bone marker measurements may be useful in identifying skeletal responders to an anabolic therapy, such as PTH, in estrogen-replete postmenopausal women with glucocorticoid-induced osteoporosis.

Bone loss. Quantitative imaging techniques for assessing bone mass in rheumatoid arthritis

Osteoporosis is associated with low bone mass and microarchitectural deterioration of bone tissue with clinical manifestation of low trauma fractures. Rheumatoid arthritis (RA) is a risk factor due to generalized and articular bone loss. This minireview presents past and current bone mass measurement techniques in RA. These techniques include: plain radiographs, absorptiometry, quantitative computed tomography (QCT) and ultrasound. The most widely used technique is dual x-ray absorptiometry (DXA). RA patients have lower bone mass as compared with normals and substantial bone loss may occur early after the onset of disease. Measurement of bone mineral density (BMD) at the hand using either DXA or ultrasound maybe a useful tool in the management of RA patients.

Assessment of a new quantitative ultrasound calcaneus measurement: precision and discrimination of hip fractures in elderly women compared with dual X-ray absorptiometry

The incidence of osteoporotic hip fracture increases in postmenopausal women with low hip bone mineral density (BMD). Dual X-ray absorptiometry (DXA) is the most commonly used technique for the assessment of bone status and provides good measurement precision. However, DXA affords little information about bone architecture. Quantitative ultrasound (QUS) systems have been developed to evaluate bone status for assessment of fracture risk. Our study was designed to assess a new QUS system from Hologic, the Sahara; to compare it with a previous model, the Walker-Sonix UBA 575+; and to investigate whether it is able to discriminate between women with and without fracture. Using both ultrasound devices, the measurements were performed at the heels of 33 postmenopausal women who had recently sustained hip fracture. A control group of 35 age-matched postmenopausal women was recruited for comparison. The total, neck and trochanter femoral BMD values were assessed using DXA for both groups. QUS and DXA measurements were significantly lower in fractured patients (p < 0.005) than in the control group. The short-term, mid-term and standardized short-term precisions were used to evaluate the reproducibility of the two QUS systems. The Sahara showed a better standardized coefficient of variation for broadband ultrasound attenuation (BUA) than did the UBA 575+ (p < 0.001). The correlation of BUA and speed of sound (SOS) between the two QUS devices was highly significant, with an r value of 0.92 for BUA and 0.91 for SOS. However, the correlation between DXA and ultrasound parameters ranged from 0.28 to 0.44. We found that ultrasound measurements at the heel were significant discriminators of hip fractures with odds ratios (OR) ranging from 2.7 to 3.2. Even after adjusting the logistic regressions for total, neck or trochanter femoral BMD, QUS variables were still significant independent discriminators of hip fracture. The areas under the ROC curves of each ultrasound parameter ranged from 0.75 to 0.78, and compared very well with femoral neck BMD (p > 0.05). In conclusion, our study indicated that the calcaneal QUS variables, as measured by the Sahara system can discriminate hip fracture patients equally as well as hip DXA.

A new method for quantitative ultrasound measurements at multiple skeletal sites: first results of precision and fracture discrimination

We investigated a new multisite quantitative ultrasound device that measures the acoustic velocity in axial transmission mode along the cortex. Using a prototype of the Omnisense (Sunlight Ultrasound Technologies, Rehovot, Israel), we tested the performance of this instrument at four sites of the skeleton: radius, ulna, metacarpal, and phalanx. Intraobserver (interobserver) precision errors ranged from 0.2% to 0.3% (0.3% to 0.7%) for triplicate measurements with repositioning. Fracture discrimination was tested by comparing a group of 34 women who had previously suffered a fracture of the hip, spine, ankle, or forearm to a group of 28 healthy women who had not suffered a fracture. Age-adjusted standardized odds ratios ranged from 1.6 to 4.5. Except for the ulna the sites showed a significant fracture discrimination (p < 0.01). The areas under the receiver operating curves (ROC) curves were from 0.88 to 0.89 for radius, metacarpal, and phalanx. A combination of the results from the three sites showed a significant increase of the ROC area to 0.95 (p < 0. 05). Our results show promising performance of this new device. The ability to measure a large variety of sites and the potential to combine these measurements are promising with regard to optimizing fracture risk assessment.

Comparison of six calcaneal quantitative ultrasound devices: precision and hip fracture discrimination

Quantitative ultrasound (QUS) is now accepted as a useful tool in the management of osteoporosis. There are a variety of QUS devices clinically available with a number of differences among them, including their coupling methods, parameter calculation algorithms and sites of measurement. This study evaluated the abilities of six calcaneal QUS devices to discriminate between normal and hip-fractured subjects compared with the established method of dual-energy X-ray absorptiometry (DXA). The short-term and mid-term precisions of these devices were also determined. Thirty-five women (mean age 74.5+/-7.9 years) who had sustained a hip fracture within the past 3 years, and 35 age-matched controls (75.8+/-5.6 years) were recruited. Ultrasound measurements were acquired using six ultrasound devices: three gel-coupled and three water-coupled devices. Bone mineral density was measured at the hip using DXA. Discrimination of fracture patients versus controls was assessed using logistic regression analysis (expressed as age- and BMI-adjusted odds ratios per standard deviation decrease with 95% confidence interval) and receiver operating characteristics (ROC) curve analysis. Measurement precision was standardized to the biological range (sCV). The sCV ranged from 3.14% to 5.5% for speed of sound (SOS) and from 2.45% to 6.01% for broadband ultrasound attenuation (BUA). The standardized medium-term precision ranged from 4.33% to 8.43% for SOS and from 2.77% to 6.91% for BUA. The pairwise Pearson correlation coefficients between different devices was highly significant (SOS, r = 0.79-0.93; BUA, r = 0.71-0.92). QUS variables correlated weakly, though significantly, with femoral BMD (SOS, r = 0.30-0.55; BUA, r = 0.35-0.61). The absolute BUA and SOS values varied among devices. The gel-coupled devices generally had a higher SOS than water-coupled devices. Bone mineral density (BMD) and BUA were weakly correlated with weight (r = 0.48-0.57 for BMD and r = 0.18-0.54 for BUA), whereas SOS was independent of weight. All the QUS devices gave similar, statistically significant hip fracture discrimination for both SOS and BUA measures. The odds ratios for SOS (2.1-2.8) and BUA (2.4-3.4) were comparable to those for femoral BMD (2.6-3.5), as were the area under the curve (SOS, 0.65-0.71; BUA, 0.62-0.71; BMD, 0.65-0.74) from ROC analysis. Within the limitation of the sample size all devices show similar diagnostic sensitivity.

Comparison of digitized images with original radiography for semiquantitative assessment of osteoporotic fractures

We validated a vertebral fracture assessment (VFA) workstation developed by our group for semiquantitative assessment of vertebral fractures in large-scale, multicenter osteoporosis drug trials. Baseline and follow-up spine radiographs (lateral views) of 50 patients who participated in a clinical trial were digitized and were archived on CD-ROM. Both original radiographs and the digitized images were independently assessed by three experienced radiologists. Prevalent fracture scores of vertebrae were rated in increments of 1 on a 4-point scale. Incident fractures were defined as any worsening of grade on follow-up films. Generally good to excellent agreement among the three readers was found between the two methods, with kappa scores (kappa) from 0.91 to 0.96 for prevalence of fractures, and from 0.80 to 0.90 for incidence of fractures. Reproducibility (intra-reader variability) of each method was comparable. For assessing prevalent fracture, kappa was from 0.87 to 0.96 using radiographs, and from 0.87 to 0.94 using VFA images. For incident fractures, the kappa was from 0.78 to 0.89 using radiographs, and from 0.82 to 0.88 using VFA images. Level-specific agreement between the two approaches was consistent. Overall, there is no difference between readings of digital images and readings of conventional radiographs. The quality of the new VFA for visualization of vertebral fracture is excellent.

Comparison of an imaging heel quantitative ultrasound device (DTU-one) with densitometric and ultrasonic measurements

The purpose of this study was to evaluate a new imaging ultrasound scanner for the heel, the DTU-one (Osteometer MediTech, Denmark), by comparing quantitative ultrasound (QUS) results with bone mineral density (BMD) of the heel and femur from dual X-ray absorptiometry (DXA), and by comparing the DTU-one with another QUS device, the UBA 575+. The regions of interest in the DXA heel scan were matched with the regions evaluated by the two QUS devices. 134 healthy and 16 osteoporotic women aged 30-84 years old were enrolled in the study. In vivo short-term precision of the DTU-one for broadband ultrasound attenuation (BUA) and speed of sound (SOS) was 2.9% and 0.1%, respectively, and long-term precision was 3.8% and 0.2%, respectively. Highest correlations (r) between QUS and BMD measurements were achieved when comparing DTU-one results with BMD in matched regions of the DXA heel scan. Correlation coefficients (r) were 0.81 for BUA and SOS. Highest correlations with the UBA 575+ were 0.68 and 0.72, respectively. The comparison of BMD in different femoral sites with BUA and SOS (DTU-one) varied from 0.62 to 0.69 when including the entire study population. The correlation between BMD values within different sites of the femur tended to be higher (from r = 0.81 to 0.93). When comparing BUA with BUA and SOS with SOS on the two QUS devices, the absolute QUS values differed significantly. However, correlations were relatively high, with 0.76 for BUA and 0.82 for SOS. In conclusion, the results of the new quantitative ultrasound device, the DTU-one, are highly correlated (r = 0.8) with results obtained using the UBA 575+ and with BMD in the heel. The precision of the DTU-one is comparable to other QUS devices for BUA and is high for SOS.

Vertebral fractures in osteoporosis: a new method for clinical assessment

Vertebral fractures are the most common consequence of osteoporosis, and are an important risk factor for subsequent fractures. Patients with reduced bone mineral density (BMD) and vertebral fractures have significantly increased risk for future fractures, indicating great potential for the combined use of fracture assessment and BMD in risk evaluation. Despite the established importance of fractures, however, vertebral assessment is not typically performed in the clinical evaluation of patients at risk for osteoporosis. Radiographs are the accepted standard for assessment of fractures, but are rarely obtained in osteoporosis assessment for a variety of practical reasons, including cost, radiation dose, and the lack of office-based radiological facilities. Clinical assessment of fractures is difficult because most are asymptomatic. Consequently, this strong risk factor for osteoporotic fractures is often overlooked. High-resolution lateral spine images, obtained on advanced fan-beam dual X-ray absorptiometry (DXA) systems, provide a practical, low-radiation dose, point-of-care methodology for assessment of vertebral fractures, and have the potential to address this important clinical need. In this article, we review the importance of vertebral fractures and the methods of assessing them. We also review clinical data supporting the feasibility of visual evaluation of lateral spine images obtained using a fan-beam DXA system, and discuss the potential positive impact of this new methodology on clinical patient evaluation.

Visual assessment of vertebral deformity by X-ray absorptiometry: a highly predictive method to exclude vertebral deformity

The accurate identification of prevalent vertebral fractures is important in both the clinical and research setting as they are associated with increased risk of further fracture and irreversible clinical consequences. This study reports a direct comparison of prevalent vertebral deformity identification using X-ray absorptiometry (XA) scans, acquired on a dual-energy X-ray absorptiometry (DXA) machine, and conventional radiographs in a diverse group of 161 postmenopausal women, ranging from healthy subjects with normal bone mineral density (BMD) to osteoporotic subjects with multiple vertebral deformities. Deformities were identified by a trained operator by visual assessment of the XA scans (VXA) and semiquantitatively by an experienced radiologist on the conventional radiographs (XSQ). Subjects were recruited prospectively and were triaged according to their VXA results into normal, equivocal and definite deformity groups. VXA and XSQ demonstrated good agreement (96.3%, K = 0.79) in classifying vertebrae as normal or deformed in the 1978 of 2093 vertebrae deemed analyzable on both the XA scans and conventional radiographs. VXA showed good sensitivity (91.9%) in the identification of moderate/severe XSQ deformities and an excellent negative predictive value (98.0%) was produced when VXA was used to distinguish subjects without vertebral deformities from those with possible or definite deformities on a per subject basis. The majority of disagreement between the two methods resulted from different classification of mild wedge and endplate deformities and the poor visualization of upper thoracic vertebrae on the XA scans. Agreement improved, particularly on a per subject basis, when analysis was restricted to the vertebral levels from L4 to T7. Visual triage of XA scans by a trained operator would seem to be swift, convenient and cost-effective method, with excellent negative predictive value, to distinguish subjects with very low risk of vertebral deformities from those with possible deformities. These 'normal' subjects can then be excluded prior to performing conventional radiographs and further time-consuming and costly methods of vertebral deformity assessment such as XSQ by an experienced radiologist and/or quantitative morphometry. VXA may prove useful in the clinical evaluation of patients at risk of osteoporosis as an adjunct to BMD scans or in the selection of subjects for osteoporosis-related clinical trials.

Association of prevalent vertebral fractures, bone density, and alendronate treatment with incident vertebral fractures: effect of number and spinal location of fractures. The Fracture Intervention Trial Research Group

Vertebral fractures are the most common osteoporotic fracture and are associated with significant pain and disability. Prior vertebral fracture and low bone mineral density (BMD) are strong predictors of new vertebral fracture. Using data from 6082 women, ages 55-80 years, in the Fracture Intervention Trial (a randomized, placebo-controlled trial of the antiresorptive agent, alendronate), we explored the association of the number of prior vertebral fractures with the risk of new fractures and whether this association is influenced by the spinal location of fractures. The risk of future vertebral fractures increased with the number of prevalent fractures, independently of age and BMD; in the placebo group, more than half of the women with five or more fractures at baseline developed new vertebral fractures, compared to only 3.8% of women without prior vertebral fractures. The magnitude of association with an increased risk of future vertebral fractures was equal for prevalent fractures located in either the "lower" (T12-L4) (relative risk [RR] = 2.9; 95% CI = 1.9, 3.6) or "upper" (T4-10) spine (RR = 2.6; 95% CI = 1.9, 3.6). We found no evidence that the effectiveness of alendronate in reducing the risk of future vertebral fracture was attenuated in women with up to five or more prevalent fractures, or that it varied by the location of prevalent fractures. However, prevalent vertebral fractures in any location were more strongly associated with risk of new fractures in the upper (RR = 5.2; 95% CI = 3.2, 8.3) than in the lower spine (2.3; 1.6, 3.3). In addition, each 1 SD decrease in spinal BMD was associated with a 2.1 (1.7, 2.6) times greater odds of new fracture in the upper spine, compared with 1.5 (1.3, 1.8) for the lower spine. These findings suggest that, in older women, osteoporosis may be a stronger risk factor for new fractures in the upper (vs. lower) thoracolumbar spine, although we found no evidence that the location of prior fractures should influence treatment decisions. Physicians should recognize that prior vertebral fractures are a strong risk factor for future fractures, and consider treating such patients to reduce their risk of subsequent fractures.

An in vitro investigation of the dependence on sample thickness of the speed of sound along the specimen

To measure the speed of sound (SOS), most quantitative ultrasound (QUS) devices use the transmission mode, whereby two transducers are placed on opposite sides of the sample. This mode is limited to a few specific skeletal sites because of the varying configuration of bone geometry and varying amounts of overlying soft tissue at most other sites. The aim of this study was to address the dependence of SOS measured along the sample on the thickness and composition of the bone sample. Bovine samples from mid-femur and trochanter, and perspex phantoms were used. We prepared the perspex samples in the shapes of blocks and cylinders to investigate the effect of wall thickness on SOS. The thickness of the blocks was decreased in decrements of 1 mm; a 22 mm diameter hole was drilled through the cylindrical samples and the hole size was gradually increased. The second configuration was also used with the bovine samples. For each experimental set-up five SOS measurements were acquired, with the probe aligned along the sample and a mean value computed. All measurements were taken with castor oil as the coupling agent, and in the cylindrical cases, the oil was used to fill the tube. The measurement precision determined as the root mean square coefficient of variation (RMSCV) was determined to be 0.14% and 0.65% for perspex and bovine samples respectively. The measured SOS on the perspex phantom (2760+/-4 m/s) was within the published values for bulk velocity. It was observed that for both perspex and bovine samples the SOS was independent of sample wall thickness greater than the wavelength (2.2 mm, 2.7 mm and 3.5 mm for perspex, trochanter and mid-femur respectively). The SOS decreased with sample wall thickness smaller than the wavelength in concordance with theoretical predictions. The SOS values obtained for bovine samples reflected either totally cortical (mid-femur) or a composite of cortical and cancellous bone (trochanter).

MR imaging findings of lateral ulnar collateral ligament abnormalities in patients with lateral epicondylitis

OBJECTIVE

The purpose of this paper was to use MR imaging to determine whether a relationship exists between lateral epicondylitis and abnormalities of the lateral ulnar collateral ligament.

SUBJECTS AND METHODS

The study group comprised 35 consecutive patients who were referred for MR imaging to rule out lateral epicondylitis. On MR imaging, "lateral epicondylitis" was defined as increased signal intensity of the extensor tendons close to their insertion on the lateral epicondyle. The severity of the lateral epicondylitis was graded as mild, moderate, or severe. The origin of the lateral collateral ligamentous complex was characterized, and the lateral ulnar collateral ligament was graded as normal, thickened, partially torn, or torn. Eleven patients underwent elbow surgery after the initial MR examination.

RESULTS

In 15 patients, MR imaging revealed characteristics of mild lateral epicondylitis. In 13 of these patients, the lateral ulnar collateral ligament was normal; one patient showed a thickened ligament; and one patient had a thinned ligament. In 11 patients, MR imaging showed features of moderate lateral epicondylitis. In eight of these patients, the lateral ulnar collateral ligament was thickened, and in the remaining three patients the ligament was normal. All nine patients with severe lateral epicondylitis showed abnormalities of the lateral ulnar collateral ligament on MR imaging. In one of these patients the lateral ulnar collateral ligament was thickened, in three patients we saw a partial tear, and in the remaining five patients we saw a complete tear of the ligament.

CONCLUSION

In our study, MR imaging features of lateral epicondylitis were often associated with thickening and tears of the lateral ulnar collateral ligament.

Effects of risedronate treatment on vertebral and nonvertebral fractures in women with postmenopausal osteoporosis: a randomized controlled trial. Vertebral Efficacy With Risedronate Therapy (VERT) Study Group

CONTEXT

Risedronate, a potent bisphosphonate, has been shown to be effective in the treatment of Paget disease of bone and other metabolic bone diseases but, to our knowledge, it has not been evaluated in the treatment of established postmenopausal osteoporosis.

OBJECTIVE

To test the efficacy and safety of daily treatment with risedronate to reduce the risk of vertebral and other fractures in postmenopausal women with established osteoporosis.

DESIGN, SETTING, AND PARTICIPANTS

Randomized, double-blind, placebo-controlled trial of 2458 ambulatory postmenopausal women younger than 85 years with at least 1 vertebral fracture at baseline who were enrolled at 1 of 110 centers in North America conducted between December 1993 and January 1998.

INTERVENTIONS

Subjects were randomly assigned to receive oral treatment for 3 years with risedronate (2.5 or 5 mg/d) or placebo. All subjects received calcium, 1000 mg/d. Vitamin D (cholecalciferol, up to 500 IU/d) was provided if baseline levels of 25-hydroxyvitamin D were low.

MAIN OUTCOME MEASURES

Incidence of new vertebral fractures as detected by quantitative and semiquantitative assessments of radiographs; incidence of radiographically confirmed nonvertebral fractures and change from baseline in bone mineral density as determined by dual x-ray absorptiometry.

RESULTS

The 2.5 mg/d of risedronate arm was discontinued after 1 year; in the placebo and 5 mg/d of risedronate arms, 450 and 489 subjects, respectively, completed all 3 years of the trial. Treatment with 5 mg/d of risedronate, compared with placebo, decreased the cumulative incidence of new vertebral fractures by 41 % (95% confidence interval [CI], 18%-58%) over 3 years (11.3 % vs 16.3%; P= .003). A fracture reduction of 65% (95% CI, 38%-81 %) was observed after the first year (2.4% vs 6.4%; P<.001). The cumulative incidence of nonvertebral fractures over 3 years was reduced by 39% (95% CI, 6%-61 %) (5.2 % vs 8.4%; P = .02). Bone mineral density increased significantly compared with placebo at the lumbar spine (5.4% vs 1.1 %), femoral neck (1.6% vs -1.2%), femoral trochanter (3.3% vs -0.7%), and midshaft of the radius (0.2% vs -1.4%). Bone formed during risedronate treatment was histologically normal. The overall safety profile of risedronate, including gastrointestinal safety, was similar to that of placebo.

CONCLUSIONS

These data suggest that risedronate therapy is effective and well tolerated in the treatment of women with established postmenopausal osteoporosis.

Tendinosis and tears of gluteus medius and minimus muscles as a cause of hip pain: MR imaging findings

OBJECTIVE

This study was conducted to determine the prevalence of tendinosis and tears of gluteus medius and minimus muscles in patients presenting with buttock, lateral hip, or groin pain; describe the MR imaging findings; and discuss their probable relationship to the greater trochanteric pain syndrome.

SUBJECTS AND METHODS

Two hundred fifty MR imaging examinations of the hip were performed for the evaluation of buttock, lateral hip, or groin pain. The findings were reviewed for changes in the morphology or signal intensity of gluteus medius and minimus muscles and tendons and for any peritendinous abnormality including distention of regional bursae.

RESULTS

Thirty-five studies met our criterion of showing either tendinosis or tears of gluteus medius and minimus muscles as the primary positive finding. Eight patients had complete retracted tears of the gluteus medius, and 14 patients had partial tears; in 13 patients, MR findings were consistent with tendinosis. The gluteus minimus muscle was also involved in 10 patients. MR imaging findings were the same as those described for tears and tendinosis of other regions of the body. Surgical proof of a tendon tear was obtained in six patients.

CONCLUSION

Tendinopathy of the hip abductors and gluteus medius and minimus muscles was a common finding on MR imaging in our patients with buttock, lateral hip, or groin pain. Tendinopathy is probably a frequent cause of the greater trochanteric pain syndrome, a common regional pain syndrome that can mimic other important conditions causing hip pain including avascular necrosis and stress fracture. Moreover, it is likely that trochanteric bursitis is associated with tendinopathy.

Denervation syndromes of the shoulder girdle: MR imaging with electrophysiologic correlation

OBJECTIVE

To investigate the use of MR imaging in the characterization of denervated muscle of the shoulder correlated with electrophysiologic studies.

DESIGN AND PATIENTS

We studied with MR imaging five patients who presented with shoulder weakness and pain and who underwent electrophysiologic studies. On MR imaging the distribution of muscle edema and fatty infiltration was recorded, as was the presence of masses impinging on a regional nerve.

RESULTS

Acute/subacute denervation was best seen on T2-weighted fast spin-echo images with fat saturation, showing increased SI related to neurogenic edema. Chronic denervation was best seen on T1-weighted spin-echo images, demonstrating loss of muscle bulk and diffuse areas of increased signal intensity within the muscle. Three patients showed MR imaging and electrophysiologic findings of Parsonage Turner syndrome. One patient demonstrated an arteriovenous malformation within the spinoglenoid notch, impinging on the suprascapular nerve with associated atrophy of the infraspinatus muscle. The fifth patient demonstrated fatty atrophy of the teres minor muscle caused by compression by a cyst of the axillary nerve and electrophysiologic findings of an incomplete axillary nerve block.

CONCLUSION

MR imaging is useful in detecting and characterizing denervation atrophy and neurogenic edema in shoulder muscles. MR imaging can provide additional information to electrophysiologic studies by estimating the age (acute/chronic) and identifying morphologic causes for shoulder pain and atrophy.

Reduction of vertebral fracture risk in postmenopausal women with osteoporosis treated with raloxifene: results from a 3-year randomized clinical trial. Multiple Outcomes of Raloxifene Evaluation (MORE) Investigators

CONTEXT

Raloxifene hydrochloride, a selective estrogen receptor modulator, prevents bone loss in postmenopausal women, but whether it reduces fracture risk in these women is not known.

OBJECTIVE

To determine the effect of raloxifene therapy on risk of vertebral and nonvertebral fractures.

DESIGN

The Multiple Outcomes of Raloxifene Evaluation (MORE) study, a multicenter, randomized, blinded, placebo-controlled trial.

SETTING AND PARTICIPANTS

A total of 7705 women aged 31 to 80 years in 25 countries who had been postmenopausal for at least 2 years and who met World Health Organization criteria for having osteoporosis. The study began in 1994 and had up to 36 months of follow-up for primary efficacy measurements and nonserious adverse events and up to 40 months of follow-up for serious adverse events.

INTERVENTIONS

Participants were randomized to 60 mg/d or 120 mg/d of raloxifene or to identically appearing placebo pills; in addition, all women received supplemental calcium and cholecalciferol.

MAIN OUTCOME MEASURES

Incident vertebral fracture was determined radiographically at baseline and at scheduled 24- and 36-month visits. Nonvertebral fracture was ascertained by interview at 6-month-interim visits. Bone mineral density was determined annually by dual-energy x-ray absorptiometry.

RESULTS

At 36 months of the evaluable radiographs in 6828 women, 503 (7.4%) had at least 1 new vertebral fracture, including 10.1% of women receiving placebo, 6.6% of those receiving 60 mg/d of raloxifene, and 5.4% of those receiving 120 mg/d of raloxifene. Risk of vertebral fracture was reduced in both study groups receiving raloxifene (for 60-mg/d group: relative risk [RR], 0.7; 95% confidence interval [CI], 0.5-0.8; for 120-mg/d group: RR, 0.5; 95% CI, 0.4-0.7). Frequency of vertebral fracture was reduced both in women who did and did not have prevalent fracture. Risk of nonvertebral fracture for raloxifene vs placebo did not differ significantly (RR, 0.9; 95% CI, 0.8-1.1 for both raloxifene groups combined). Compared with placebo, raloxifene increased bone mineral density in the femoral neck by 2.1 % (60 mg) and 2.4% (120 mg) and in the spine by 2.6% (60 mg) and 2.7% (120 mg) P<0.001 for all comparisons). Women receiving raloxifene had increased risk of venous thromboembolus vs placebo (RR, 3.1; 95% CI, 1.5-6.2). Raloxifene did not cause vaginal bleeding or breast pain and was associated with a lower incidence of breast cancer.

CONCLUSIONS

In postmenopausal women with osteoporosis, raloxifene increases bone mineral density in the spine and femoral neck and reduces risk of vertebral fracture.

Diagnostic agreement of quantitative sonography of the calcaneus with dual X-ray absorptiometry of the spine and femur

OBJECTIVE

The aim of our study was to evaluate the diagnostic agreement between quantitative sonography of the calcaneus and dual X-ray absorptiometry (DXA) of the spine and femur for revealing osteoporosis.

SUBJECTS AND METHODS

In 1252 patients (795 women, 54.9+/-15 years old; 457 men, 50.5+/-15 years old [mean+/-SD]), bone mineral density measurements of the lumbar spine (posteroanterior, L1-L4) and the proximal femur (neck, trochanter, intertrochanteric region, total proximal femur, and Ward's triangle) and quantitative sonographic measurements of the stiffness of the calcaneus were performed. The presence of osteoporosis is defined, according to the World Health Organization criteria, as a T-score lower than -2.5. The percentage of patients below the threshold (prevalence of osteoporosis) was calculated for each imaging technique. The diagnostic agreement in identifying individuals as osteoporotic was assessed using kappa scores.

RESULTS

Forty-nine percent of the women and 42% of the men were classified as osteoporotic by quantitative sonography, 32% of women and 30% of men by DXA of the spine, and 23-54% of women and 16-54% of men by the different regions of interest revealed on femoral DXA. Kappa analysis showed the diagnostic agreement among these measures to be generally poor (kappa = .28-.41 [women] and .25-.45 [men]).

CONCLUSION

The considerable diagnostic disagreement between quantitative sonography and DXA could cause confusion in the daily practice of radiology and make establishing the correct diagnosis a difficult task. The choice of imaging technique influences which patients are diagnosed as osteoporotic.

Biochemical markers of bone turnover and prediction of hip bone loss in older women: the study of osteoporotic fractures

To examine the ability of commercially available biochemical markers of bone formation and resorption to predict hip bone loss, we prospectively obtained serum and timed 2-h urine specimens from 295 women age 67 years or older who were not receiving estrogen replacement therapy. Serum was assayed for two markers of bone formation: osteocalcin (OC) and bone-specific alkaline phosphatase (BALP). Urine specimens were assayed for four markers of bone resorption: N-telopeptides (NTX), free pyridinolines (Pyr), free deoxypyridinoline (Dpyr), and C-telopeptides (CTX). Measurements of hip bone mineral density were made at the time the samples were collected and then repeated an average of 3.8 years later. Higher levels of all four resorption markers were, on average, significantly associated with faster rates of bone loss at the total hip, but not at the femoral neck. Women with OC levels above the median had a significantly faster rate of bone loss than women with levels below the median, but there was no significant association between levels of BALP and hip bone loss. The sensitivity and specificity of higher marker levels for predicting rapid hip bone loss was limited, and there was considerable overlap in bone loss rates between women with high and low marker levels. We conclude that higher levels of urine NTX, CTX, Pyr, Dpyr, and serum OC are associated with faster bone loss at the hip in this population of elderly women not receiving estrogen replacement therapy, but these biochemical markers have limited value for predicting rapid hip bone loss in individuals.

An evaluation of a new gel-coupled ultrasound device for the quantitative assessment of bone

Quantitative ultrasound (QUS) is now being accepted as a tool in the assessment of bone status. Most QUS devices measure broadband ultrasound attenuation (BUA) and speed of sound (SOS). A newly introduced device, the Acoustic Osteo-Screener (AOS-100), measures both SOS and an attenuation related parameter called the transmission index (TI) and provides a derived parameter called osteo sono-assessment index (OSI). The purpose of this study was to examine the reproducibility of this new device, compare the results with the UBA 575+ and evaluate the effect of using two platforms to compensate for different foot sizes on the measured values. 83 subjects aged 21-89 years, who gave informed consent, were recruited. Subjects were assigned to three different groups determined by age and health status. The short-term measurement precision (expressed as root mean square coefficient of variation) of SOS (0.13-0.16%) and TI (1.18-1.96%) was similar to and better than that obtained for the UBA 575+. Significant negative correlations were found between the differences in SOS measured with the two platforms (adaptors to adjust the position of the foot relative to the foot plate) and foot length (p < 0.0001). This implies that small feet are more influenced by the differences of measured location. All QUS parameters measured with the small platform were found to be significantly smaller than those with the large platform (p < 0.0001). The mean percentage differences were 0.6% in SOS, 2.8% in TI and 4.3% in OSI with the large foot platform giving larger value results. Proper use of the platforms resulted in more reproducible SOS and TI. This study demonstrated that the newly developed AOS-100 parameters TI and OSI were highly reproducible. This study also demonstrated that the use of an inappropriate platform can cause discrepancies in QUS readings and poor reproducibility.

Vertebral fractures and mortality in older women: a prospective study. Study of Osteoporotic Fractures Research Group

BACKGROUND

Osteoporotic fractures, including clinically detected vertebral fractures, are associated with increased mortality. However, only one third of vertebral fractures are diagnosed. It is unknown whether vertebral fractures, whether clinically apparent or not, are associated with greater mortality.

OBJECTIVES

To test the hypothesis that women with prevalent vertebral fractures have greater mortality than those without fractures and to describe causes of death associated with vertebral fractures.

DESIGN

Prospective cohort study with mean follow-up of 8.3 years.

SETTING

Four clinical centers in the United States.

PARTICIPANTS

A total of 9575 women aged 65 years or older and enrolled in the Study of Osteoporotic Fractures.

MEASUREMENTS

Vertebral fractures by radiographic morphometry; calcaneal bone mineral density; demographic, medical history, and lifestyle variables; blood pressure; and anthropometric measures. In a subset of 606 participants, thoracic curvature was measured during a second clinic visit.

MAIN OUTCOME MEASURES

Hazard ratios for mortality and cause-specific mortality.

RESULTS

At baseline, 1915 women (20.0%) were diagnosed as having vertebral fractures. Compared with women who did not have a vertebral fracture, women with 1 or more fractures had a 1.23-fold greater age-adjusted mortality rate (95% confidence interval, 1.10-1.37). Mortality rose with greater numbers of vertebral fractures, from 19 per 1000 woman-years in women with no fractures to 44 per 1000 woman-years in those with 5 or more fractures (P for trend, <.001). In particular, vertebral fractures were related to the risk of subsequent cancer (hazard ratio, 1.4;95% confidence interval, 1.1-1.7) and pulmonary death (hazard ratio, 2.1;95% confidence interval, 1.4-3.0). In the subset of women who underwent thoracic curvature measurements, severe kyphosis was also related to pulmonary deaths (hazard ratio, 2.6;95% confidence interval, 1.3-5.1).

CONCLUSION

Women with radiographic evidence of vertebral fractures have an increased mortality rate, particularly from pulmonary disease and cancer.

Larger increases in bone mineral density during alendronate therapy are associated with a lower risk of new vertebral fractures in women with postmenopausal osteoporosis. Fracture Intervention Trial Research Group

OBJECTIVE

To investigate whether the incidence of vertebral fractures is related to the magnitude of change in bone mineral density (BMD) during alendronate treatment.

METHODS

Women in this study were age 55-81 years (n = 2,984). While participating in the Fracture Intervention Trial, they received 5 mg/day of alendronate for 2 years followed by 10 mg/day for the remaining 12-30 months of the study. Their BMD was measured at baseline and at 12 and 24 months, and spine radiographs were obtained at baseline and again at 36 or 48 months to identify new vertebral fractures.

RESULTS

After 12 months of alendronate treatment, 35% of participants had increases of > or =3% in total hip BMD, and 21% had either decreased total hip BMD or no change. Women who had larger increases in total hip BMD during the first 12 months had a lower incidence of new vertebral fractures during the entire followup period. Only 3.2% of women with increases of > or =3% in total hip BMD experienced new vertebral fractures, whereas twice as many women (6.3%) whose BMD declined or stayed the same experienced new fractures (adjusted odds ratio 0.45, 95% confidence interval 0.27-0.72). Similar patterns were observed for spine BMD at 12 months, and for both sites using change in BMD at 24 months.

CONCLUSION

Women with increases of > or =3% in BMD during the first 1 or 2 years of alendronate treatment had the lowest incidence of new vertebral fractures. These findings suggest that, among women taking antiresorptive agents, greater increases in BMD are associated with lower risk of new vertebral fractures.

Accuracy of T2-weighted fast spin-echo MR imaging with fat saturation in detecting cartilage defects in the knee: comparison with arthroscopy in 130 patients

OBJECTIVE

The purpose of this study was to assess the accuracy of routine T2-weighted MR imaging in detecting and grading articular cartilage lesions in the knee compared with arthroscopy.

SUBJECTS AND METHODS

We examined 130 consecutive patients who underwent MR imaging and arthroscopy of the knee for suspected internal derangement. MR imaging consisted of axial and coronal T2-weighted fast spin-echo sequences with fat saturation and sagittal T2-weighted spin-echo sequences. Each single plane was evaluated and graded for the presence and appearance of articular cartilage defects using a standard arthroscopic grading scheme adapted to MR imaging.

RESULTS

Of the 86 arthroscopically proven abnormalities, 81 were detected on MR imaging. Sensitivity of the T2-weighted fast spin-echo sequence with fat saturation was 61% for the coronal plane alone and 59% for the axial plane alone. Specificity for each plane was 99%. Sensitivity for the sagittal T2-weighted spin-echo sequence was 40%, and specificity was 100%. Sensitivity of the combination of axial and coronal T2-weighted fast spin-echo sequences with fat saturation and sagittal T2-weighted spin-echo sequence compared with arthroscopy for revealing cartilage lesions was 94%, specificity was 99%, and accuracy was 98%. Sensitivity of coronal and axial T2-weighted fast spin-echo sequences with fat saturation was 93%, and specificity was 99%. Fifty-five lesions (64%) were identically graded on MR imaging and arthroscopy. Seventy-eight lesions (90%) were within one grade using MR imaging and arthroscopy, and 84 lesions (97%) were within two grades using MR imaging and arthroscopy.

CONCLUSION

T2-weighted fast spin-echo MR imaging with fat saturation is an accurate and fast technique for detecting and grading articular cartilage defects in the knee. The combination of the axial and coronal planes offers sufficient coverage of articular surfaces to provide a high sensitivity and specificity for chondral defects.

Does combining the results from multiple bone sites measured by a new quantitative ultrasound device improve discrimination of hip fracture?

There is a growing interest in the use of quantitative ultrasound (QUS) measurements as an alternative to current radiation-based bone densitometry techniques for the noninvasive assessment of fracture risk. While most of the commercialized ultrasound devices measure only single predefined peripheral skeletal sites, the Omnisense prototype (Sunlight Ltd., Israel) can be used on multiple bones, including the spinous processes. In this study, we examined the ability of speed of sound measured at the calcaneus, distal third and ultradistal radius, proximal third phalanx, metacarpal, capitate, patella, and the posterior process of the thoracic spine to differentiate subjects with hip fractures from normal controls. Seventy-nine postmenopausal Caucasian Israeli women who had sustained an atraumatic fracture of the proximal femur within the last 6 months were recruited from the local population (mean age 80 +/- 8.9 years). As controls, 295 postmenopausal Caucasian Israeli women without osteoporotic fractures were also included (mean age 70 +/- 8.7 years). Discrimination of hip fractures with QUS at all ultrasound sites was highly statistically significant (p < 0.01) (odds ratios [ORs] = 1.4-3.0; area under the ROC curve [AUC] 77-92%), except for the hand metacarpal. Distal radius and calcaneus measurements (ORs = 2.4 and 3.0) were the best discriminators of hip fracture patients from controls. Using a forward selective linear regression model, the discriminator values of combined assessment at two sites were investigated. There was moderate improvement in diagnostic value, but the best combination was the calcaneus with the distal radius, which improved the AUC by 3% and raised both the sensitivity and specificity to 94%. These data demonstrate the encouraging potential of improving discrimination of hip fracture by using multiple-site ultrasonic measurements.

Shoulder MRI after surgical treatment of instability

OBJECTIVE

To analyze magnetic resonance imaging (MRI) findings of the shoulder after an instability operation.

MATERIALS AND METHODS

Physical examinations, radiographs and MRI of 10 patients after anterior glenoid bone block insertion for ventral instability were compared. MRI included T1-weighted spin-echo (TR = 600, TE = 20 ms) and T2*-weighted gradient-echo sequences (TE = 600, TE = 18, Flip = 30 degrees) in the axial, oblique-coronal and oblique-sagittal planes.

RESULTS

No patient suffered from recurrent subluxation. We found fusion of the bone block with the anterior glenoid in seven cases, dislocation of the bone block without contact to the glenoid in one case, and no visible bone block in two cases. On MRI, the bone block showed either signal intensity equivalent to fatty bone marrow (n = 4) or was devoid of signal consistent with cortical bone or bone sclerosis (n = 4). In all patients, a low signal intensity mass, 2-4 cm in diameter, was visible next to the glenoid insertion site.

CONCLUSION

Insertion of a bone block onto the anterior glenoid induces formation of scar tissue, increasing the stability of the shoulder joint. This scar is well visible on MRI and forms independently of the behavior of the bone block itself. MRI is ideally suited for evaluating postoperative shoulder joints after bone-grafting procedures.

Chondrosarcoma of the foot: imaging, surgical and pathological correlation of three new cases

The foot is an uncommon location for chondrosarcoma. The presentation, diagnosis, pathological findings, surgical treatment and follow-up of three patients with chondrosarcoma in this rare location are presented. Though nonspecific, MR imaging findings were of aid in the diagnosis and treatment planning of these patients. If the diagnosis of this tumor is rapidly made, a tumor excision instead of limb amputation may be sufficient treatment at surgery.