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B Cortet

Publications and source records attributed to B Cortet.

At least 19 recordsLinked to original sources
PubMed2006

A clinical tool to determine the necessity of spine radiography in postmenopausal women with osteoporosis presenting with back pain.

BACKGROUND: Vertebral fractures are underdiagnosed, although the resulting mortality and morbidity in postmenopausal women with osteoporosis is now recognised. In a population of postmenopausal women with osteoporosis and back pain, symptoms may be related to vertebral fractures or degenerative changes of the spine. AIM: To evaluate a population of postmenopausal women presenting with back pain and factors associated with vertebral fractures which were assessable in a clinical setting in order to determine the necessity for spine radiography. METHODS: Patient questioning and physical examination were carried out and spinal radiographic data collected from 410 postmenopausal women with osteoporosis, with an average age of 74 years, who consulted a rheumatologist for back pain. Of these, 215 (52.4%) patients were diagnosed with at least one vertebral fracture. Logistic regression was used to identify the most relevant clinical features associated with existing vertebral fractures, and to derive a quantitative index of risk. RESULTS: The model included six parameters: age, back pain intensity, height loss, history of low trauma non-vertebral fractures, thoracic localisation of back pain and sudden occurrence of back pain. The scoring system, or the quantitative index, had a maximal score of 16. For a score >or=7, the probability of existing vertebral fracture was >or=43%. The correlation between this quantitative index and the logistic model probability was 0.98, suggesting an excellent and highly significant approximation of the original prediction equation. CONCLUSIONS: From six clinical items, an index was built to identify women with osteoporosis and back pain who should have spine radiography. This simple tool may help clinicians to optimise vertebral fracture diagnosis and to make a proper therapeutic decision.

Aged↗
PubMed2006

Lack of efficacy of a third tumour necrosis factor alpha antagonist after failure of a soluble receptor and a monoclonal antibody.

OBJECTIVE: Some studies have highlighted the potential benefits of switching from infliximab to etanercept, or after failure of one or the other treatment. To our knowledge, no study has assessed the potential benefits of using the three anti-TNF-alpha agents that are currently available. The objective of this retrospective study was to assess the response to treatment in RA patients who had received the three anti-TNF-alpha agents, namely infliximab, etanercept and adalimumab. METHODS: Among a cohort of 364 patients undergoing biological treatments since the year 2000, 284 had been treated with only one anti-TNF-alpha agent. Our assessment focused on the records of 70 patients who had received at least two anti-TNF-alpha agents. Twenty of the 70 patients had received all three anti-TNF-alpha agents (infliximab, etanercept and adalimumab). Effectiveness was assessed using the 28-joint Disease Activity Score (DAS28), and adverse events were reported for each anti-TNF-alpha treatment. RESULTS: Of the 70 patients who had received two anti-TNF-alpha agents, 32 had switched from an antibody to a soluble receptor; 45% of them had a good clinical response to the soluble receptor. Thirty patients had switched from a soluble receptor to an antibody; 45% of them had a good clinical response to the antibody. Only eight patients had switched from an antibody to another antibody with an efficiency score of 33%. Of the 20 patients who had received three anti-TNF-alpha agents, seven had stopped receiving the third anti-TNF-alpha agent due to lack of effectiveness. In this group of non-responders to the third anti-TNF-alpha treatment, all patients except one had stopped receiving the two previous anti-TNF-alpha agents, without adverse events, for lack of effectiveness. These patients were deemed resistant to anti-TNF-alpha therapy. CONCLUSIONS: Resistance to anti-TNF-alpha agents is rare. The lack of effectiveness of a soluble receptor and of one of the anti-TNF-alpha antibodies predicts the lack of effectiveness of the third anti-TNF-alpha treatment.

Adalimumab↗
PubMed2005

[Rheumatoid arthritis and cystic fibrosis].

INTRODUCTION: Inflammatory arthropathies are rare complications of cystic fibrosis (CF). We describe three cases of rheumatoid arthritis (RA) occurring in patients with this disease. OBSERVATIONS: Among the 100 patients under the care of the adult CF centre in Lille 3 presented with RA. This developed at the ages of 17, 44 and 19 years with a FEV1 of 53%, 42% and 94% respectively. They were 2 women and 1 man, with CFTR gene mutation delta F508 (1 homozygote and 2 heterozygotes) and positive sweat tests. They were colonised with Staphylococcus aureus, and rheumatoid factor and/or anti CCP antibodies were positive. The appearance and progression of RA were associated with exacerbations of bronchial infection and deterioration of respiratory function. In 2 patients the RA was continuously progressive despite intensive treatment involving high dose cortico-steroids, methotrexate (ineffective) followed by leflunomide (complicated by intractable respiratory infection). CONCLUSION: There is an increased incidence of RA in our patient population with CF. The new serum markers of RA including anti CCP are of diagnostic interest. The evolution of the two diseases is related and seems to be dependent on the level of infection leading to therapeutic problems.

Adult↗
PubMed2004

Relationship between computed tomographic image analysis and histomorphometry for microarchitectural characterization of human calcaneus.

The present study aimed to characterize the relationships between several variables reflecting bone microarchitecture assessed by both computed tomographic (CT) image analysis and histomorphometry (conventional CT system) at the calcaneus. A total of 24 cadaveric specimens were studied. The mean age at death was 78 +/- 10 years (range, 53-93 years). A total of 15 sagittal sections (1 mm in width and spaced 2 mm apart) were selected for CT analysis; 6 undecalcified sections (7 microm) were analyzed for histomorphometry. The histomorphometric analysis was performed on a Leica Quantimet Q570 image analyzer. Features measured by both methods were: bone volume/tissue volume (BV/TV), trabecular thickness (Tb.Th), trabecular separation (Tb.Sp), trabecular number (Tb.N), interconnectivity index (ICI), number of nodes (N Nd), number of terminus (N Tm), node-to-node strut count (NNS), node-to-terminus strut count (NTS), terminus-to-terminus strut count (TTS), marrow space star volume (SV), Euler number (EN), and fractal dimension (FD). The coefficient of correlations' values (simple linear regression) between histomorphometry and CT image analysis varied according to the parameters selected. R values were high for BV/TV, Tb.N, and Tb.Sp (range, 0.69-0.90; P < 0.01). R values were less significant for some variables also obtained from the binary image: SV (0.5, P < 0.05) and EN (0.43, P < 0.05). Finally R values were also significant for (two) variables obtained from skeletonized images, i.e., N Nd (0.4, P < 0.05) and N Tm (0.61, P < 0.01). Other correlations were not statistically significant. Moreover, for some variables the relationships between the two methods (CT analysis and histomorphometry) seemed best-described by using nonlinear models. For example, a logarithmic model was more appropriate for SV (r = 0.71, P < 0.01), N Nd (r = 0.52, P < 0.01). Finally the relationship between apparent (App) N Tm and N Tm was most satisfying when using an exponential model (r = 0.64, P < 0.01). In conclusion, trabecular bone structure measures determined on CT images show highly significant correlations with those determined using histomorphometry. The level of correlation varies according to the type of method used for characterizing bone structure, however, and the strongest correlations were found for the most basic features (Parfitt's parameters). Finally, for some variables, nonlinear models seem more appropriate.

Absorptiometry, Photon↗
PubMed2004

Sex hormone-binding globulin, estradiol, and bone turnover markers in male osteoporosis.

The role of estrogen deficiency in male osteoporosis is still under discussion. One hundred five subjects, 65 of them suffering from osteoporosis (mean age, 53.9 years) and 40 age-matched controls were studied. Osteoporosis was defined by a T score < -2.5 in the lumbar spine or at the femoral neck. Forty-one (63.1%) of the subjects had a history of low-energy fractures, involving vertebrae in 33 cases (50.8%). Osteoporosis was considered to be idiopathic in 33 subjects (50.8%) for whom no etiology could be found. We measured levels of total estradiol (pg/ml, with a detection threshold of 4 pg/ml), total testosterone (ng/ml), and their carrier protein, that is, sex hormone-binding globulin (SHBG, pmol/ml). Various markers of bone remodeling were also measured. Two of them provide an estimate of bone formation-osteocalcin (OC) and bone alkaline phosphatase (BAP). Two others evaluate bone resorption-procollagen type I C-terminal telopeptide (ICTP) and serum C-telopeptide of type I collagen (sCTX). There was no significant difference in estradiol levels between controls and osteroporosis patients. We did not find any significant correlation between estradiol levels and spinal bone mineral density (BMD) (r = 0.15, P > 0.05), and the relationship between estradiol levels and BMD at the femoral neck was weak (r = 0.25, P < 0.05). On the other hand, SHBG was significantly higher in the osteoporotic patients than in controls (P < 0.01). This difference persisted after adjustment for body mass index (BMI) and after exclusion of patients with a condition known to increase SHBG levels. Moreover, this carrier protein was negatively correlated with BMD at the femoral neck (r = -0.37, P < 0.01) and at the lumbar spine (r = -0.27, P < 0.05). SHBG also correlates strongly with sCTX (r = 0.37, P < 0.01). Finally, logistic regression analysis showed that serum SHBG concentration was significantly associated with the presence of fractures; the odds ratio of having a fracture was 2.04 [95% confidence interval (CI) 1.2-3.4, P < 0.01] for each increase of 1 standard deviation (SD) in the patient's SHBG level. The stronger relationship was nearly the same for the whole group and for patients with idiopathic osteoporosis. This study therefore suggests that SHBG may play a key role in male patients with idiopathic or secondary osteoporosis. It shows that serum SHBG concentration is increased in middle-aged men with osteoporosis and is correlated with hip, spine BMD, and sCTX levels. Finally, our findings are in agreement with previous studies which suggest that serum SHBG is a new biological marker of fracture risk in men.

Adult↗
PubMed2003

Does quantitative ultrasound of bone reflect more bone mineral density than bone microarchitecture?

Relationships among quantitative ultrasound of bone (QUS), bone mineral density (BMD) and bone microarchitecture have been poorly investigated in human calcaneus.Twenty-four specimens, from 12 men and 12 women (mean age 78 +/- 10 years; range 53-93), removed from cadavers were studied. The feet were axially sectioned above the ankle. Two variables were measured for QUS (Achilles, Lunar): broadband ultrasound attenuation (BUA) and speed of sound (SOS). A third variable, the stiffness index (SI), which is a combination of both BUA and SOS, was also calculated. BMD (a lateral view) was measured on a QDR 2000 densitometer (Hologic). Bone microarchitecture was assessed by computed tomography (CT) using a conventional CT-system. Fifteen sagittal sections (1 mm in width and 2 mm apart) were selected for CT. Methods used for characterizing bone microarchitecture consisted in structural (trabecular network characterization) and a fractal analyses. The relationships between QUS and bone microarchitecture were assessed by simple linear regression analysis with and without adjustment for BMD (partial correlation) and by backward stepwise regression analysis. Strong relationships were found between BMD and QUS. Adjusted r(2) values were 0.545 for SOS and 0.717 for SI. Two microarchitectural variables were also significantly correlated with both SOS and SI: apparent trabecular separation (App Tr Sp) and trabecular bone pattern factor (App TBPF). After adjustment for BMD few correlations between QUS and microarchitectural variables were always significant. Adjusted squared semipartial coefficients of correlation (rsp2) values between SOS and bone microarchitecture were 6%, 6.8%, 13.2% and 4.6% for App BV/TV, App Tr Sp, App TBPF and fractal dimension (FD), respectively. For SI, corresponding figures were 3.7%, 4.1%, 5.2% and 3.2%. Backward stepwise regression analysis using BMD and microarchitecture showed a slight increase of r(2) values that varied from 8.4% for SI to 17.8% for SOS, compared with BMD alone. The current study suggests that although BMD is a major determinant of acoustic properties of human calcaneus, significant density independent relationships with bone microarchitecture should also be taken into account.

Aged↗
PubMed2002

Quantitative ultrasound of bone in male osteoporosis.

Quantitative ultrasound (QUS) measurement, a different approach to bone fragility assessment, has already been attempted in women with osteoporosis but rarely in men. In order to test its value and ability to identify osteoporotic men, a case-control prospective study was conducted using the Lunar Achilles, a device that measures attenuation and velocity parameters. Broadband ultrasound attenuation (BUA), speed of sound (SOS) and stiffness index (SI), a composite parameter, were assessed through the heel of 66 osteoporotic patients, and compared with the results in 35 controls. Patients had sustained a low-trauma fracture and/or had a lumbar and/or femoral bone mineral density (BMD) more than 2.5 SD below the young male reference value. As expected, all QUS parameters were statistically lower in patients, as were the dual-energy X-ray absorptiometry (DXA) measurements at the hip and lumbar spine. The two methods were compared for their ability to predict the risk of osteoporotic fractures. The odds ratios (ORs), with their 95% confidence limits, for fractures per 1 SD decrease were significant, especially for SOS and SI (OR = 2.3 [1.4-3.6] and 2.1 [1.3-3.3] respectively) and to a lesser extent for BUA (1.6 [1.0-2.4]). Our study suggests that QUS is associated with a history of low-trauma fracture in men; sensitivity is, however, less than when results are compared with BMD measurements (OR = 2.8 [1.6-5.0] and 3.4 [1.6-7.0] for lumbar spine and hip, respectively). Prospective studies are required before QUS can be recommended for clinical use in male osteoporosis.

Absorptiometry, Photon↗
PubMed2002

Computed tomography image analysis of the calcaneus in male osteoporosis.

The present study aimed to characterize bone microarchitecture assessed by computed tomography (CT) at the calcaneus in male subjects suffering from osteoporosis. Seventy-nine subjects were assessed (45 with osteoporosis and 34 control subjects matched for age). Osteoporosis was defined according to the World Health Organization classification either at the lumbar spine or at the femoral neck. Thirty-three subjects (73%) had a past history of low-energy fracture mainly represented by vertebral fractures (24/33). Nine axial sections (1 mm in width and 2 mm apart) were selected for each subject. Bone microarchitecture analysis was performed using structural (binary and skeletonized images but also skeletonization from gray levels) and fractal analyses. Bone densitometry by dual-energy X-ray absorptiometry (DXA) at the calcaneus was also performed in 73 cases. Bone mineral density (BMD) was decreased in osteoporotic patients compared with controls both at the lumbar spine and hip and also at the calcaneus (p<0.01). Also 14 microarchitectural features among 25 measured were significantly different between the two groups (p<0.01). The odds ratio for fracture per 1 control group standard deviation decrease were also significant for 13 structural features but also for BMD at the calcaneus. The odds ratios after adjustment for BMD at the calcaneus were significant for the following features (p<0.05): number of valleys, 2.8 (1.2-6.9); trabecular partition, 3.3 (1.3-7.9); apparent trabecular spacing, 1.8 (1.0-3.1); trabecular bone pattern factor, 2.2 (1.1-4.3); Euler number, 3.0 (1.1-8.7); node-to-terminus strut count, 3.3 (1.4-7.8); terminus-to-terminus strut count, 2.9 (1.2-6.9); and fractal dimension, 3.7 (1.5-9.7). Few and weak correlations were found between BMD at the calcaneus measured with DXA and features obtained from CT, suggesting that these two methods give different information about bone status. In conclusion, male osteoporosis is a disease characterized by decreased bone mass but also by microarchitectural deterioration of bone tissue which is partly independent of BMD.

Absorptiometry, Photon↗
PubMed2001

Quantitative ultrasound of bone and markers of bone turnover in Cushing's syndrome.

Quantitative ultrasound (QUS) of bone is a valuable tool in the assessment of postmenopausal osteoporosis. QUS and new markers of bone turnover have been poorly assessed in Cushing's syndrome, however. Twenty-five patients with Cushing's syndrome (20 women, 3 men; mean age +/- SEM: 38+/-2 years) were studied and compared with 35 age- and sex-matched control patients (mean age +/- SEM: 38+/-2 years). The following variables were measured in both groups: QUS parameters at the heel (BUA; SOS; Stiffness Index, SI); bone mineral density (BMD) at both the lumbar spine (LS) and femoral neck (FN) by dual-energy X-ray absorptiometry; and serum markers of bone turnover (osteocalcin, procollagen type I N- and C-terminal propeptides (PINP and PICP), bone alkaline phosphatase (BAP), procollagen type I C-terminal telopeptide (ICTP) and urinary type I collagen C-telopepetide breakdown products (CTX)). Both BUA and SI were decreased in patients with Cushing's syndrome (p<0.01) but not SOS (p=0.08). BMD was also strongly decreased in Cushing's syndrome, at both the LS and FN (p<0.005). The two markers of bone turnover statistically significantly different between the two groups were osteocalcin (mean + SEM: 3.5 + 0.7 ng/ml (Cushing's syndrome) vs 6.4+/-0.5 ng/ml (controls, p<0.01)) and CTX (mean +/- SEM: 148.7+/-17.1 microg/mmol Cr (Cushing's syndrome) vs 220.8+/-22.9 microg/mmol Cr (controls), p<0.05). The areas under the receiver operating characteristic curve (AUC) were 0.72 (BUA), 0.73 (SI), 0.90 (BMD(LS)), 0.81 (BMD(FN)), 0.83 (osteocalcin) and 0.64 (CTX) respectively. AUC was significantly higher for BMD(LS) than for both BUA and SI (p<0.05). Conversely AUC was not statistically significantly different for BMDFN as compared with either BUA or SI. AUC was also higher for osteocalcin than for other markers of bone turnover. In conclusion, QUS of bone seems to be a relevant tool for assessing bone involvement in Cushing's syndrome. QUS does have a lower sensitivity compared with DXA, however, and the relevance of QUS cannot be ascertained until some longitudinal data are forthcoming. Except for CTX, the other new markers of bone turnover assessed in this study (PINP, PICP, BAP and ICTP) do not seem of interest in Cushing's syndrome.

Absorptiometry, Photon↗
PubMed2001

Should percutaneous vertebroplasty be used to treat osteoporotic fractures? An update.

Acrylic cement vertebroplasty is being increasingly used to treat osteoporotic vertebral compression fractures (VCFs), although no controlled studies supporting this trend have been published. Vertebroplasty remains controversial as a treatment for osteoporotic fractures because it is a local response to a systemic disease and because the pain caused by osteoporotic fractures usually subsides within a few days or weeks. Current data suggest that pain severity may decrease by half, on average, in 90-100% of patients. Although vertebroplasty is usually well tolerated, serious neurological complications have been reported in a few patients. The most common adverse event is nerve root pain, usually caused by leakage of the cement into the intervertebral foramen. Whether vertebroplasty is followed by an increased risk of osteoporotic fractures in the adjacent vertebras remains unclear. Resorbable cements are being developed and may provide better results than the acrylic cements used today. At present, acrylic cement vertebroplasty to treat osteoporotic VCFs is appropriate in only a minority of patients selected carefully by a multidisciplinary team including a rheumatologist.

Arthroplasty↗
PubMed2001

Management of male osteoporosis.

UNLABELLED: The objective of this study was to evaluate the efficacy of treatments for male osteoporosis selected based on the cause of the disease. METHODS: Sixty-three men with osteoporosis (T-score at the lumbar spine and/or femoral neck lower than -2.5) with a mean age of 53+/-11 years were studied. Forty-three (68.3%) had a history of fracturing without trauma (vertebral fractures, 37 patients, 57%). Treatments were as follows: idiopathic osteoporosis: calcium and vitamin D supplements (N = 10) or cyclical etidronate for 2 weeks followed by calcium and vitamin D supplements for 76 days (N = 29); moderate idiopathic phosphate diabetes: calcitriol and phosphate (N = 15); idiopathic hypercalciuria: hydrochlorothiazide (N = 6); and hypogonadism: testosterone (N = 3). RESULTS: Percentage change in bone mineral density (mean +/- standard error of the mean) after 18 months: calcium and vitamin D (lumbar spine: 0.6+/-2; femoral neck: 2.2+/-2.2); etidronate (lumbar spine: 3.6+/-1.4*; femoral neck: 0.5+/-1); calcitriol (lumbar spine: 7.0+/-3.5*; femoral neck: 0.0+/-1.4); thiazide diuretic (lumbar spine: 1+/-3.2; femoral neck: -2.3+/-3.7); and testosterone (lumbar spine: 6.8+/-6.4; femoral neck: 2.5+/-2.7), where *P < 0.05 versus baseline. Gastrointestinal side effects occurred in three patients (4.8%), including two on calcitriol-phosphate therapy and one on etidronate therapy. Of the six (9.5%) patients who experienced incident fractures, four were on etidronate, one on calcitriol-phosphate, and one on calcium-vitamin D. No patients discontinued their treatment because of side effects. CONCLUSION: Etidronate and the combination of calcitriol-phosphate produce a significant increase in lumbar spine bone mass in men with idiopathic osteoporosis or moderate idiopathic phosphate diabetes.

Absorptiometry, Photon↗
PubMed2001

Comparative efficacy and safety study of etidronate and alendronate in postmenopausal osteoporosis. effect of adding hormone replacement therapy.

OBJECTIVES: To compare the efficacy and safety of etidronate and alendronate in patients with postmenopausal osteoporosis and to assess the efficacy of either bisphosphonate in combination with hormone replacement therapy (HRT). PATIENTS AND METHODS: In this pragmatic study, the main efficacy criterion was the mean annual change in bone mineral density (BMD). Patients who had a past or current history of etidronate or alendronate treatment for postmenopausal osteoporosis with at least 18 months follow-up and an evaluation in 1999 were eligible. Recruitment was in an outpatient clinic with a special focus on metabolic bone diseases. Osteoporosis was defined as at least one low-energy fracture or as a lumbar spine or femoral neck BMD decrease to at least 2.5 SD below the mean in young women. HRT was not an exclusion criterion provided treatment duration was longer than 1 year. Etidronate was given cyclically (14-day courses in a dosage of 400 mg/d separated by 76-day intervals with calcium and vitamin D supplementation) and alendronate was given daily in a dosage of 10 mg/d. RESULTS: Of the 99 patients who met our inclusion criteria, 53 received etidronate (including 23 on HRT) and 46 alendronate (18 on HRT). Repeat BMD measurements were obtained in 88 patients, including 11 who stopped their bisphosphonate therapy within the first year of use because of adverse events. Lumbar spine BMD (mean +/- SD) increased significantly both in the etidronate group (+2.1% +/- 0.7%/year) and in the alendronate group (+5.3% +/- 0.9%/year). The increase was significantly greater with alendronate (P< 0.01). The lumbar spine BMD increase was largest in the patients on alendronate and HRT (+6.5% +/- 1.4%/year) and was smallest (and nonsignificant) in the patients on etidronate without HRT (+ 1.2% +/- 0.8%). Femoral neck BMD showed no significant changes in any group. In the intention-to-treat analysis, fractures occurred in 12 etidronate patients (22.6%) and six (13.0%) alendronate patients (nonsignificant). Adverse events requiring bisphosphonate discontinuation before the scheduled date of the follow-up BMD measurement occurred in one patient (1.9%) in the etidronate group (generalized osteomalacia) and in ten patients (21.7%) in the alendronate group (upper or lower gastrointestinal tract symptoms in six and four patients, respectively; P < 0.01). CONCLUSION: Both etidronate and alendronate significantly increased lumbar BMD, but the effect was significantly more marked with alendronate. Conversely, adverse effects, most notably gastrointestinal symptoms, were more common with alendronate, so that premature treatment discontinuation because of adverse events were more common in the alendronate group. Both differences should be taken into account when selecting the best drug for a patient with postmenopausal osteoporosis.

Aged↗
PubMed2000

Bone ultrasonometry and turnover markers in primary hyperparathyroidism.

Quantitative ultrasound (QUS) of bone and new markers of bone remodeling have been poorly investigated in mild primary hyperparathyroidism (PHPT). In this study 26 patients (20 females and 6 males) were evaluated. BUA and SOS were measured by QUS at the heel. Markers of bone remodeling assessed were bone alkaline phosphatase (BAP), osteocalcin (OC), procollagen type I N- and C-terminal propeptides (PINP et PICP), and procollagen type I C-terminal telopeptide in blood and urine (ICTP and CTX). Bone mineral density (BMD) was measured at the lumbar spine (LS), femoral neck (FN), and Ward's triangle (WT). The control group comprised 35 sex- and age-matched subjects. The statistically significant variables between the two groups were (P < 0.05) BUA, BMD(LS), BMD(FN), BMD(WT), BAP, and OC. Corresponding z-scores were -0.55 +/- 0.75, -0.66 +/- 0.77, -0.66 +/- 0.71, -0.67 +/- 0.52, 1.87 +/- 3.87, and 1.93 +/- 3.53, respectively. Although PICP and PINP levels were higher in PHPT patients as compared with controls, the difference was not significant. Several markers of bone turnover were moderately correlated with both QUS (r = -0.39 to -0.55) and BMD (r = -0.48 to 0.63). In conclusion QUS seems to be a relevant tool in the assessment of bone status for patients with mild PHPT.

Absorptiometry, Photon↗
PubMed2000

In vivo comparison between computed tomography and magnetic resonance image analysis of the distal radius in the assessment of osteoporosis.

In a prospective case-control cross-sectional study, we investigated the usefulness of both computed tomography (CT) and magnetic resonance (MR) image analysis of the distal radius for distinguishing a small sample of fractured osteoporotic women from control women regardless of bone mineral density. The study population included 12 subjects who were divided into two groups according to their bone status. The first group consisted of six women with at least one vertebral fracture occurring in the absence of high-energy trauma, and the second group consisted of six women without disease affecting bone mass or bone metabolism. Cross-sectional and coronal slices were obtained from both CT and MR systems. For CT images, the slice thickness was 1000 jim and the plane resolution was approx 200 jim x 200 jim. MR images were obtained from a 1.5-T imager with a two-dimensional spin-echo Ti-weighted sequence leading to a slice thickness of 2000 jim and a plane resolution of 195 jim x 195 jim. Bone texture analysis was performed using fractal and structural methods leading to the measurement of 23 features. Most of the structural variables derived from histomorphometric parameters and were measured after segmentation from a binary or a skeletonized image. Bone densitometry was measured by dual-energy X-ray absorptiometry both at the lumbar spine and the nondominant femoral neck. On cross-sectional slices, 12 variables, mainly obtained from structural analysis, were significantly different between the two groups for CT images (p < 0.05) against two variables only for MR images (p < 0.05). The number of variables statistically different between the two groups was significantly higher for CT images compared with MR images (p = 0.003). In the same way, odds ratios for fracture per 1 control group standard deviation decrease were significant for 10 variables on CT images, whereas, in contrast, none of the variables measured on MRI images led to significant odds ratios. The results obtained for the two methods on coronal slices were poorer without a difference between either CT or MR images in terms of discrimination between fracture and nonfracture subjects. In conclusion, this study suggests that bone texture analysis obtained from CT compared with MRI offers a best discrimination between controls and osteoporotic patients, probably the result to the spatial resolution. which is better for CT than for MR images.

Absorptiometry, Photon↗
PubMed2000

Does high-resolution computed tomography image analysis of the distal radius provide information independent of bone mass?

This study aimed to investigate the usefulness of computed tomography (CT) image analysis of the distal radius for comparing two groups of postmenopausal women matched for age and bone mineral density at both the lumbar spine and femoral neck. The first one consisted of 16 women with at least one vertebral fracture and the second consisted also of 16 women without disease affecting bone mass or bone metabolism. Eight slices were selected in each patient: four consecutive coronal slices and four consecutive axial slices. Bone texture analysis was performed using structural methods leading to the measurement of 24 features. Most of the structural variables derived from histomorphometric parameters and were measured after segmentation from a binary or a skeletonized image. Nine variables were significantly different between the two groups on axial slices: valley number, valley surface area, apparent bone volume/tissue volume (BV/TV), apparent trabecular separation, apparent trabecular number, trabecular bone pattern factor, trabecular skeletal length, node count, and node-to-node strut count. Also four variables were significantly different between osteoporotic women and controls on coronal slices: apparent BV/TV, trabecular partition, node-to-node strut count, and terminus-to-terminus strut count. In conclusion this study suggests that bone texture analysis could yield additional data on bone mass for explaining bone strength and therefore could be used for improving the prediction of fracture risk.

Absorptiometry, Photon↗
PubMed2000

Long-term efficacy of percutaneous drill-biopsy under computed tomography guidance of osteoid osteomas of the hip and femur. A review of seven cases.

UNLABELLED: En bloc surgical excision of osteoid osteomas of the hip and femur is difficult because of problems with tumor boundary identification and the need to use internal fixation or bone grafting. We report our experience with seven cases treated by percutaneous drill-biopsy under computed tomography guidance. PATIENTS: Six adults and one child with a mean age of 22 years treated since 1995. All seven patients reported insomnia due to pain during a mean of 10 months, improved by aspirin or other nonsteroidal anti-inflammatory agents. The tumor was seen on plain radiographs in four cases and on computed tomography scans in all seven cases. Magnetic resonance imaging was diagnostic in only two cases. The tumor was in the femoral neck in four patients, in the acetabulum in one, in the proximal femur in one, and at the distal diaphyseal-metaphyseal junction of the femur in one. METHOD: A trephine was used to remove the tumor under computed tomography guidance during a short general anesthesia. RESULTS: No serious complications were recorded. Full weight bearing was allowed starting at the forty-eighth hour in six of the seven patients. Immediate pain relief and a full recovery were obtained in every case. Results were excellent in four patients and good in three after a follow-up of 14 to 44 months. CONCLUSION: Percutaneous drill-biopsy of osteoid osteomas is a valuable alternative to conventional surgery in patients with tumors at sites that are difficult to access. The technique allows early weight bearing and ensures a full recovery.

Adolescent↗