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Biomedical subjects

C L Benhamou

Publications and source records attributed to C L Benhamou.

At least 37 records · Page 2Linked to original sources
PubMed1999

Skull bone mass deficit in prepubertal highly-trained gymnast girls.

It is known that impact loading sport can increase the bone mineral density in the stressed sites of the skeleton in athletes. However, non weight-bearing sites are seldom studied in healthy young girl athletes. In order to study the effects of a long term intensive training on the non-stressed region of the skeleton (skull), we investigated both highly-trained girl athletes, involved in sports requiring or not significant impact loading on the skeleton and a girl control group. Bone mineral content (BMC) and density (BMD) were measured in the whole body, at lumbar spine, femoral neck, trochanter, Ward's triangle, radius, head and ribs, in 60 prepubertal girls including 12 swimmers, 32 gymnasts and 16 controls. Measurements were made by DXA. There were no statistical differences between the groups as regards age, height, body weight, body mass index, lean tissue mass and dietary calcium intake. Mean BMD in gymnasts was statistically higher than in other groups for radius (p < 0.001), femoral neck (p < 0.05) and Ward's triangle (p < 0.05) while there was no difference between swimmers and controls. Head BMC was significantly lower in gymnasts compared to other groups (241.9+/-41 g vs. 285.8+/-34.7 g and 291.1+/-50.2 g respectively in swimmers and controls, p < 0.001). The same observation was made for head BMD (p < 0.01). When body weight was used as a covariant, the contribution of the head BMC to the whole body was significantly lower (p < 0.001) in gymnasts (24.97%) than in swimmers (27.88%) and controls (27.77%). When compared between groups, the slopes of the regressions for head/whole body BMC or BMD were significantly lower in gymnasts (p < 0.05) than in other groups. These data suggest that in prepubertal children the increased bone density induced by gymnastic training in the stressed sites of the body could be related to a decreased skull bone mass.

Bone Density↗
PubMed1999

Bone material acquisition and somatic development in highly trained girl gymnasts.

The present study was conducted to investigate both skeletal and somatic developments in a group of highly trained prepubertal girl gymnasts at the beginning of their peak bone mass acquisition. The experimental group included 14 gymnasts who had trained 12-15 h per wk for 3 y before starting the study. The control group consisted of 15 non-exerciser children and 6 swimmers training for 5-6 h/wk. Body composition and bone mineral density (BMD) of the total body, lumbar spine, non-dominant hip and radius were measured using dual-energy X-ray absorptiometry. Calculation of bone age and measurement of body height and weight were done. All measurements and analyses were carried out twice with a 1-y interval by the same technician. There were no differences between groups in age, bone age, body height and weight and lean tissue mass at the start of the study and 1 y later. The somatic changes observed between the first and second years tended to be greater in gymnasts compared to controls, except for body height. At the first and second investigations, BMD values in the gymnasts were statistically higher than in the controls at all skeletal sites, but not for the whole body (from p < 0.05 to p < 0.001, depending on the site). Percentage changes in BMD pre-investigation compared with post-investigation tended to be greater in gymnasts. Variations in lean mass, bone age and fat mass were found to be the best independent predictors of annual changes in BMD for total body, lumbar spine, trochanter and femoral neck sites. These results suggested that high-volume impact loading training could promote a higher annual gain in bone mineral acquisition at the strained body sites in prepubertal girls without affecting somatic growth dimensions.

Body Height↗
PubMed1999

Alternaria infection of the skin and joints. A report of two cases involving the hand.

Alternaria is a fungus that is usually saprophytic but occasionally causes skin infections. Involvement of other structures is exceedingly rare. We report two cases in which a joint was also affected. The possible precipitating role of intraarticular glucocorticoid therapy is discussed. Both patients achieved a full recovery after itraconazole therapy, given for 12 and seven months, respectively.

Adult↗
PubMed1998

Effect of physical training on bone mineral density in prepubertal girls: a comparative study between impact-loading and non-impact-loading sports.

Physical activity is known to have an anabolic effect on bone tissue. It has been shown to increase the bone mineral density (BMD) in young adults, as well as in teenagers. But there is little information about the effect of intensive physical activity in childhood, particularly at the prepubertal stage. To examine the influence of an early intensive physical training on BMD, we have studied a group of elite prepubertal girls, at the starting phase of their peak bone mass acquisition. Subjects were engaged either in sport requiring significant impact loading on the skeleton, or in sport without impact loading. Forty-one healthy prepubertal girls took part in this study. The sport group consisted of 10 swimmers (10.5 +/- 1.4 years old) and 18 gymnasts (10.4 +/- 1.3 years old), who had performed 3 years of high-level sport training (8-12 h per week for swimmers, 10-15 h per week for gymnasts). Thirteen girls (10.7 +/- 1 years old) doing less than 3 h per week of physical activity served as a control group. BMD measurements were done using dual-energy X-ray absorptiometry. There was no statistical significant difference between groups as regards age, body height and weight, and body composition. There was no statistical significant difference between swimmers and controls for all the BMD measurements. Mean BMD in gymnasts was statistically higher than in the control group for mid-radius (+15.5%, p < 0.001), distal radius (+33%, p < 0.001), L2-4 vertebrae (+11%, p < 0.05), femoral neck (+15%, p < 0.001) and Ward's triangle (+15%, p < 0.01). Moreover, in gymnasts, BMD at radius, trochanter and femoral neck was above normative values. We conclude that physical activity in childhood could be an important factor in bone mineral acquisition in prepubertal girls, but only if the sport can induce bone strains during a long-term program: gymnastics has such characteristics, unlike swimming. Such acquisition could provide protection against risks of osteoporosis in later life, but this remains debatable.

Bone Density↗
PubMed1998

Fractal analysis of trabecular bone texture on radiographs: discriminant value in postmenopausal osteoporosis.

Trabecular bone microarchitecture cannot be routinely evaluated. We have developed and validated a fractal analysis of trabecular bone texture on calcaneus radiographs. The aim of this work was to evaluate the ability of the fractal analysis to discriminate a group of 39 postmenopausal women with osteoporotic (OP) vertebral crush fractures (68.0 +/- 10.8 years) from an age-matched control group of 39 women (68.0 +/- 10.7 years). The value of the fractal analysis was compared with the value of the femoral neck bone mineral density (FNBMD) and trochanteric bone mineral density (TRBMD). The result is expressed by the parameter Hmean (Hmean = 2 - fractal dimension). Hmean value was 0.691 +/- 0.050 in the OP group versus 0.739 +/- 0.024 in the controls, while FNBMD was 0.598 +/- 0.113 g/cm2 versus 0.645 +/- 0.109 g/cm2 and TRBMD was 0.512 +/- 0.108 g/cm2 versus 0.594 +/- 0.106 g/cm2 respectively. The statistical significance of the Hmean test (p < 0.0001) was higher than for FNBMD (p < 0.05) and for TRBMD (p = 0.0004). We used a receiver operating characteristic (ROC) curve to check this superiority. The area under the ROC curve was 0.824 for Hmean, 0.633 for FNBMD and 0.727 for TRBMD. This superiority of the Hmean ROC curve was statistically significant versus FNBMD, but not versus TRBMD. In a second analysis, we studied the subgroups of OP patients and controls with overlapping FNBMD or TRBMD values to check whether the fractal dimension test could be discriminant in these subgroups. Significant statistical differences were found for Hmean between OP patients and controls in the overlapping subgroup for FNBMD or TRBMD (respectively p = 0.006 and p < 0.02). These data confirm that the fractal analysis of texture on calcaneus radiographs is able to discriminate OP patients with vertebral crush fracture from controls. This discrimination was stronger than that obtained by FNBMD or TRBMD alone. It was also present when we compared subgroups with overlapping values of FNBMD or TRBMD.

Absorptiometry, Photon↗
PubMed1998

Fractal analysis of bone texture on os calcis radiographs compared with trabecular microarchitecture analyzed by histomorphometry.

Microarchitecture of trabecular bone is an important determinant of bone fragility; to date, its evaluation requires bone biopsy with histomorphometry analysis. Methods of noninvasive characterization of trabecular bone microarchitecture are in development and we have developed and validated a bone texture analysis applied to bone radiographs and based on fractal geometry. The aim of our study was to compare this fractal analysis of trabecular bone texture on radiographs to the trabecular microarchitecture analyzed by bone histomorphometry on os calcis biopsies. Thirty eight ossa calcis from 19 human cadavers were studied. Fractal analysis of the trabecular bone of os calcis radiographs was performed by the maximum likelihood estimator following the fractional brownian motion model. The ossa calcis were dissected, then transcortical biopsy cores focused on the fractal analysis region of interest were obtained. Structural and connectivity parameters were measured with both automatic and semiautomatic analyzers. We have found a significant relationship between the fractal Hmean parameter and structural histomorphometric indices; the best correlation was found with trabecular separation (r = -0.55; P = 0.0004). Based on a stepwise regression analysis, trabecular spacing and trabeculae number together would explain 38% of the variance of the fractal parameter. Although the relationship with connectivity indices was poor, our fractal analysis of os calcis trabecular bone texture on radiographs seemed to partially reflect the trabecular bone microarchitecture.

Aged↗
PubMed1998

Biomechanical properties of human os calcanei: relationships with bone density and fractal evaluation of bone microarchitecture.

The relationship between bone strength and bone mass is well established. The link between trabecular microarchitecture and biomechanical properties has been less extensively explored. To address this question, we have tested the mechanical behaviour of calcaneus bone samples and investigated the correlations between mechanical properties on the one hand, bone density and fractal analysis of microarchitecture on the other hand. Mechanical properties of 43 human os calcanei were determined by uniaxial compression testing of samples from tuber calcanei. Ash density, bulk density and dual energy X-ray absorptiometry of the samples were measured. Fractal analysis of the trabecular bone on calcaneus radiographs was performed by two estimators derived from the fractional Brownian motion model. The mechanical properties of human os calcis were found to correlate with age and density measurements. Fractal parameters derived from the bone texture analysis showed weaker but significant correlations with bone strength. Fractal analysis of texture could account in part for the variations of bone strength, but in this study cannot explain better than density the mechanical properties of trabecular bone. Nevertheless, it provides a non-invasive means of assessing molecular bone microarchitecture.

Aged↗
PubMed1998

Lean tissue mass is a better predictor of bone mineral content and density than body weight in prepubertal girls.

PURPOSE AND METHODS: Body weight is the most extensively studied correlate of bone mass and is widely used as a covariate in statistical evaluations of bone mineral parameters. Lean tissue mass (LTM) also correlates with bone mass. We evaluated the correlations linking each of these two parameters with bone mineral content and bone mineral density in 41 prepubertal girls, including ten swimmers, 18 gymnasts and 13 nonathletes. Lean tissue mass, bone mineral content and bone mineral density were measured using dual-energy X-ray absorptiometry (Hologic QDR-1000/W; Hologic Inc., Waltham, MA, USA). Forward stepwise multiple regression was used to evaluate correlations linking bone mineral content or density (the dependent variables) to body weight or lean tissue mass (the independent variables). RESULTS: Body weight and lean tissue mass showed strong correlations with all bone mineral content and density measurements in the simple linear regression analysis, with lean tissue mass yielding the highest Pearson's correlation coefficients. In the multiple regression model, lean tissue mass consistently explained the largest proportion of the variance, whereas body weight had little influence or was eliminated from the model. The slopes of the regression lines of bone mineral content or density on body weight were significantly steeper in the subgroup of gymnasts (P < 0.001), whereas the slopes of the regression lines of bone mineral content or density on lean tissue mass were significantly less steep in the swimmers (P < 0.05). CONCLUSION: Our data indicate that lean tissue mass is a significant predictor of bone mass in prepubertal girls and explains a larger part of the variance of bone mineral content and density than body weight. Use of body weight as a covariate in studies of bone mineral density may lead to erroneous results in prepubertal girls.

Absorptiometry, Photon↗
PubMed1997

An epidemiological study of diagnostic and therapeutic strategies in office practice patients with subacute or chronic pain in the thoracic or low back. Comparison of practices in primary care and rheumatology settings.

UNLABELLED: There is a paucity of epidemiological data on diagnostic and therapeutic practices in office practice patients with subacute or chronic pain in the thoracic or low back. STUDY OBJECTIVE: to describe diagnostic and therapeutic strategies used in such patients. PATIENTS AND METHODS: descriptive, prospective, two-month epidemiological study in 50 general practitioners and 50 rheumatologists. Each physician was asked to provide data on the demographics, clinical features, history of spinal disease, investigations, prior treatments and treatments prescribed on D0 and D30 in two patients with low back pain and two with thoracic back pain, of one to 12 months' duration. RESULTS: A total of 352 patients were included. In the 217 patients with low back pain, including 107 women and 110 men, duration of the pain was 4.3 +/- 0.2 months and mean age was 49.6 +/- 1 years; 67% of these patients were economically active and 22% were retired; 59% were recruited by rheumatologists. In the thoracic back pain group, there were 135 patients, including 82 women (61%) and 53 men, with a mean duration of pain of 3.8 +/- 0.3 months and a mean age of 47.7 +/- 1.4 years; 60% were economically active and 22% were retired; 49% were recruited by rheumatologists. A history of conservatively-treated low or thoracic back pain was reported for 95.4% of patients in the low back pain group and 94% in the thoracic back pain group. Of the patients with low back pain, 6.3% had had spinal surgery. Investigations were as follows: roentgenograms in 85% of low back pain and 75% of thoracic back pain patients, computed tomography in 11% and 5.8%, magnetic resonance imaging in 2% and 1% and laboratory tests in 14% and 20%. Ninety-one per cent of low back pain and 84% of thoracic back pain patients were already under therapy on D0. Ninety-six per cent of patients overall were given a prescription at the end of the D0 visit, for a nonsteroidal antiinflammatory drug or an analgesic in 80% of low back pain and 63% of thoracic back pain patients, for muscle relaxants in 62% and 69%, for drugs aimed at preventing gastric side effects in 19% and 9.5%, for myotonic agents in 10% and 8% and for sedatives in 5% and 11%. A local steroid injection was given to 20% of low back pain patients. Twenty-four per cent of low back pain and 14% of thoracic back pain patients missed days of work (mean, 11 +/- 1.7 days and 13 +/- 4.6 days, respectively). Physical therapy was prescribed to 36% of low back pain and 27% of thoracic back pain patients and a lumbar support belt to 17% of low back pain patients. On D30, the pain had abated in 86% of low back pain and 89% of thoracic back pain patients and complete freedom from pain was reported by 28% and 32% of patients in these two groups, respectively. Treatments prescribed on D30 were physical therapy (43% and 31%), analgesics (40% and 36%) muscle relaxants (25% and 30%), and nonsteroidal antiinflammatory drugs (23% and 12%). Conclusion. This preliminary study provides data on common practices in subacute and chronic low back and back pain and may prove useful for health care cost estimations.

Acute Disease↗
PubMed1997

Septic arthritis of lumbar facet joints. A review of six cases.

Hematogenous infection of the facet joints by pyogenic organisms is exceedingly rare. We report six cases of lumbar facet joint septic arthritis due to hematogenous spread of a pyogenic organism. A review of the literature identified ten anecdotal reports of similar cases. An analysis of these 16 cases showed that the diagnosis was based mainly on imaging study findings and that clinical data failed to discriminate between facet joint septic arthritis and infectious discitis. Increased uptake on the radionuclide bone scan was an early finding and the pattern of uptake was different from that seen in discitis. Computed tomography was the investigation that best delineated the facet joint lesions. Magnetic resonance imaging of the lumbar spine was superior over computed tomography in demonstrating spread of the infection to the epidural space and/or soft tissues and in some instances demonstrated enhancement of the infected facet joint on T1 images after gadolinium injection. Aspiration of the facet joint under fluoroscopic guidance was required only when blood cultures were negative or when the diagnosis of the septic nature of the arthritis was in doubt. Blood cultures yielded a Staphylococcus aureus in the six cases in our series. Appropriate antimicrobial therapy was successful in most cases. In our series, four of the six patients had posterior epiduritis, pyomyositis, or an abscess in the paraspinal muscles or psoas muscle, suggesting that some epidural infections or psoas muscle abscesses believed heretofore to be primary may in fact be complications of facet joint septic arthritis. Facet joint septic arthritis is a new aspect of pyogenic spinal infections that deserves to be considered in patients with febrile spinal syndromes not explained by discitis.

Abscess↗
PubMed1996

[Bone structure and mechanical resistance of the bone tissue].

The strength of bone depends on bone structure, both in terms of global geometry of the bone and the microscopic pattern of the trabecular network. Modifications in the trabecular organization, often related to the aging process, include altered anisotropy, perforations, loss of connectivity and microfractures. The microscopic architecture of trabecular bone can be studied on histomorphometric slices, the use of stereologic techniques on these slices may better reflect the changes occurring in 3 dimensions. High-resolution tomodensitometry and 3-D magnetic resonance imaging are under further evaluation. An evaluation of the fractal geometry of the trabecular network, performed on the vertebrae, calcaneus, or ulna on standard radiographs has given promising results. Bone strength is determined by resistance tests on bone tissue samples. The relationship between the applied force and bone deformation is used to determine a stress-strain curve and resistance parameters. The mechanical behavior of a given bone can be modelized by a Finite Element Analysis, the computerized model being able to predict the reaction of this bone. Ultra-sound analysis does not directly measure bone density, nor bone architecture, but would reflect both these properties. Velocity and attenuation of ultra-sounds, measured at the calcaneus or patella, are useful in distinguishing between controls and osteoporosis cases, and may have predictive value.

Adult↗
PubMed1996

Osteoclast cytomorphometry in patients with femoral neck fracture.

In patients with femoral neck fracture, nutritional deficiencies have been shown to be common. A low calcium diet and/or a reduced vitamin D intake have been suspected to cause secondary hyperparathyroidism responsible for increased bone turn over and bone loss. Parathyroid hormone (PTH) levels are increased in these patients, data which are in accordance with the pronounced changes observed on bone biopsies reflecting a true hyperparathyroidism. We have used a cytomorphometrical approach to characterize PTH-induced changes on the osteoclastic population. Osteoclasts were detected histochemically (by tartrate resistant acid phosphatase staining) on bone biopsies from 10 control subjects, 8 patients with primary hyperparathyroidism and 10 patients with a femoral neck fracture of osteoporotic origin. The maximum Feret's diameter of each osteoclast (Oc.Le) was determined with a semiautomatic image analyzer. In all groups, the frequency distribution of Oc.Le appeared positively skewed. In both hip fractured patients and primary hyperparathyroid patients, the mode of the distribution was higher (25-30 microns) than in controls (20-25 microns). When graphically converted on a probability graph, the osteoclastic populations appeared homogeneous and well described by a lognormal distribution in the three groups. However, osteoclasts appeared similarly enlarged in the groups of patients with primary hyperparathyroidism and with femoral neck fracture. PTH has been shown to increase both the recruitment of mononucleated precursors and their fusion into larger osteoclasts than controls. In the present study, a cytomorphometric method appeared able to identify the border line hyperparathyroidism in the hip fractured patients.

Adult↗
PubMed1996

Anisotropy measurements obtained by fractal analysis of trabecular bone at the calcaneus and radius.

The resistance of bone tissue is influenced not only by bone density parameters but also by bone architecture parameters, such as the microarchitecture and anisotropy of trabecular bone. We have developed and validated a fractal analysis method for studying bone microarchitecture on roentgenograms. This technique provides reproducible measurements of the fractal dimension (D) of bone, which reflects bone texture. The fractal dimension is determined in 36 different directions; the mean of these 36 values is representative of the image. A polar diagram gives the value of D according to the angle of analysis. By decomposing this diagram using polar Fourier Transform analysis, the parameters related to the shape of the polar diagram can be determined. This diagram image analysis technique has been used for other similar diagrams and applied to the results of our fractal analysis method. Diagram shape characterization may provide information on the angular distribution of results and therefore on the anisotropy of the images under study. The purpose of this study was to compare roentgenograms of the calcaneus and radius in the same subjects to determine whether texture and anisotropy parameters discriminated between these two bones. Roentgenograms of the calcaneus and radius were obtained in ten nonosteoporotic subjects. The radius had a smaller fractal dimension than the calcaneus (mean +/- standard deviation: 1.215 +/- 0.025 and 1.285 +/- 0.066, respectively; p = 0.014). Differences in the shape of the polar diagram were found between the two bones. The mean Fourier coefficient ratio C2/C4 was considerably smaller at the calcaneus (0.63 +/- 0.50) than at the radius (4.88 +/- 3.45; p = 0.005). Our method allows quantitative characterization of texture and anisotropy differences between the calcaneus and radius. The smaller fractal dimension of the radius probably reflects the simpler architecture of this non weight-bearing bone. The differences in polar diagram shape allow to evaluate anisotropy differences between the calcaneus and radius.

Adult↗
PubMed1995

Calciotropic hormones in elderly people with and without hip fracture.

The effects of age on calciotropic hormones are not completely understood. The presence of secondary hyperparathyroidism has previously been demonstrated, particularly in patients with hip fracture. The role of a disturbance of vitamin D metabolism, especially a defect in 1 alpha-hydroxylation, is debated. The aim of this study was to compare serum parathyroid hormone (PTH), osteocalcin and vitamin D metabolites (25(OH)D and 1,25(OH)2D) in osteoporotic elderly patients with hip fracture (HF) and in elderly controls. We studied 57 HF patients aged 83.9 +/- 5.9 years (mean +/- SD) and 68 controls aged 82.5 +/- 5 years recruited during two periods: 1 January and 30 April 1988 and 1989. Patients with chronic renal failure (serum creatinine above 150 mumol/l), cancer, or other metabolic bone disease were excluded. Thirty healthy young adults were studied in 1989 only for measurement of 1,25(OH)2D. (1,25(OH)2D was measured by different laboratories in 1988 and 1989 for technical reasons.) We also measured serum PTH, osteocalcin, total calcium and ionized calcium. 1,25(OH)2D levels were not statistically different between HF patients and controls for the two years, nor between HF patients and young healthy adults in 1989. 25(OH)D was decreased in HF patients (p < 0.003), as was ionized calcium. Serum PTH levels were higher in HF patients than in controls (p < 0.01). A positive correlation has been found between PTH and age in HF patients (r = 0.29; p < 0.03) and in the whole group of HF patients and controls. There was a significant decrease in osteocalcin in HF patients versus elderly controls (p < 0.04).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

[Lipid microcrystals and other rare crystals in the joints].

Although not strictly of crystalline nature, various formations can be observed in joint fluids and be responsible for "microcrystalline" arthritis. They can consist of lipidic structures (cholesterol crystals, fatty lobules, liposomes) or calcium crystalline structures such as calcium oxalate crystals detected in fluids of dialyzed chronic renal failure patients, reflecting primary or secondary oxalosis. Other phosphate calcium crystals have been identified, associated to apatite or pyrophosphate crystals, but their pathogenic role is uncertain. Charcot-Leyden crystals reflect eosinophilic arthritis. A phylogenic role may be played by corticoid suspension crystal or prosthetic debris. Lastly, some crystals can be artefacts, resulting from sampling conditions and storage of joint fluids.

Calcinosis↗
PubMed1994

Fractal organization of trabecular bone images on calcaneus radiographs.

Bone density is not the unique factor conditioning bone strength. Trabecular bone microarchitecture also plays an important role. We have developed a fractal evaluation of trabecular bone microarchitecture on calcaneus radiographs. Fractal models may provide a single numeric evaluation (the fractal dimension) of such complex structures. Our evaluation results from an analysis of images with a varying range of gray levels, without binarization of the image. It is based on the fractional brownian motion model, or more precisely on the analysis of its increment, the fractional gaussian noise (FGN). The use of this model may be considered validated if two conditions are fulfilled: the gaussian repartition and the self-similarity of our data. The gaussian repartition of intermediate lines of these images was tested on a sample of 32,800 lines from 82 images. Following a chi-square goodness-of-fit test, it was checked in 86% of these lines for alpha = 0.01. The self-similarity was tested on 20 images by two estimators, the variance method of Pentland and the spectrum method of Fourier. Self-similarity is defined by lined-up points in a log-log plot of the FGN spectrum or of the variance as a function of the lag. We found two self-similarity areas between scales of analysis ranging from 105 to 420 microns, then above 900 microns, where linear regression produced high mean correlation coefficients (r > or = 0.97). Following this validation, we studied the reproducibility of this new technique. Intra- and interobserver reproducibility, influence of transferring the region of interest, and long-term reproducibility were assessed and given CV of 0.61 +/- 0.15, 0.68 +/- 0.47, 0.53 +/- 0.16, and 2.07 +/- 0.84%, respectively. These data have allowed us to validate the use of this fractal model by checking the fractal organization of our radiographic images analyzed by the model. The good reproducibility of successive x-rays in the same subject allows us to undertake population studies and to envisage longitudinal series.

Calcaneus↗