Objective. - To look for serum factors detectable early after head injury and predictive of heterotopic bone formation.Patients and methods. - In this prospective study of a homogeneous population of 31 men with severe brain injury, blood samples were obtained 3 months after the accident, and levels of serum factors influenced by bone metabolism were compared between patients with and without heterotopic bone formation. As extensive fractures can influence serum factors, the patients without heterotopic bone formation were divided into two groups based on whether they had major fractures. Radionuclide bone scanning was used to validate patient classification.Results. - The group with heterotopic bone formation had significantly higher serum alkaline phosphatase levels (P < 0.01) and significantly lower serum leptin levels (P < 0.01), as compared to the other two groups. Body mass index and serum creatinine were comparable in the three groups.Conclusion. - Leptin may be associated with the development of heterotopic bone formation. The antiosteogenic effect of leptin mediated by hypothalamic neurons may be impaired by hypothalamic damage related to severe brain injury. (c) 2004 Elsevier SAS. All rights reserved.

The relative influence of genetic and environmental determinants on bone mass is still unclear. Using an original multicentric mode of recruitment, based on absorptiometry current practice, the hypothesis of a familial predisposition to low bone mineral content was assessed. The study was based on dual-energy X-ray absorptiometry (DXA) measurements of lumbar and femoral neck bone mineral density (BMD), using daughters of women with a low BMD (case mothers). These BMD values were compared with those of control daughters of women with a normal BMD. Case mothers (n= 72) aged 54.3 ± 4.8 years were recruited on the basis of a questionnaire and a vertebral Z-score < – 2 SD. Their healthy daughters of more than 20 years (n= 77) aged 28.2 ± 4.9 years had their vertebral and femoral BMD Z-score determined. The control groups were composed of mothers aged 54.1 ± 4.7 years, paired by age ± 2 years to the case mothers, and of their daughters of more than 20 years old, aged 27.7 ± 5.8 years. For daughters, a significant difference was found between the mean vertebral Z-scores (–0.82 ± 1.08 for cases and 0.01 ± 1.14 for controls, p < 0.0001). The difference was in the same direction but was not statistically significant for mean femoral Z-scores (–0.58 ± 1.15 for cases and –0.22 ± 1.33 for controls, p <0.073). These findings confirm the hypothesis of a familial predisposition to low BMD.

Dual Energy X-ray Absorptiometry (DXA) allows direct measurement of bone mineral content. We evaluated its interest for evaluation of porous ceramics before and after bone implantation. HA and beta-TCP implants were inserted in 3 mm diameter cavity of rabbit femur with 3 delays (T0, T12 and T24 weeks) for DXA and histomorphometric analysis. Om results show excellent new bone contact in interface implant/bone for the two ceramics. Bone ingrowth and biodegradation were more important in beta-TCP than in HA. Comparison of the sites, bone ingrowth activity was cortical > cancellous > marrow site. But biodegradation activity was marrow > cancellous > cortical site. After comparison of the two methods, we consider that DXA can bring complementary inquiries in the evaluation of porous ceramics. Its non invasive and atraumatic character should permit in vivo longitudinal survey, and analysis of biodegradation in resorbable ceramics and bone rehabitation in non resorbable ceramics.

La complexite de la Polyarthrite Rhumatoide et ses multiples consequences dans la vie quotidienne des personnes atteintes conduit a la conception d'une prise en charge en equipe pour faire face aux nombreux problemes poses, approche pluridisciplinaire dont l'initiative revient en France a l'Ecole Montpellieraine. Cette prise en charge, pour etre globale, doit regrouper l'ensemble constitue par les professionnels et les structures de sante qui ont en charge ces patients sur une aire geographique determinee : cet ensemble constitue un reseau de soins. Ainsi, aux cotes de structures hospitalieres specifiques dont le nombre est croissant, il est indispensable que cette prise en charge se fasse sur le terrain quotidien du patient. Ceci conduit au developpement d'une action sanitaire concertee, impliquant soignants et acteurs sociaux de proximite, basee elle aussi sur l'equipe pluridisciplinaire et garante d'une necessaire repartition territoriale de moyens sanitaires adaptes.

A new case of osteomesopyknosis, a rare autosomal dominant axial osteosclerosis is reported, with 4 affected members of the same family. Biochemical investigations, bone mineral content (BMC) measurement, 99mTc HMDP bone scan and microscopy of iliac crest bone and femoral head have been performed on 1 subject. A marked increase of BMC was found, without abnormality of biochemical data. Microscopy of bone showed an increase of trabecular thickness, and a low rate of bone turnover. No abnormality of mineralization was found on microradiographs.

The effects of corticosteroid on bone were examined in female growing rabbits treated with 0.7 mg/kg per day prednisolone for 5 months. The evolution of whole-body total bone mineral measured by dual-photon absorptiometry showed a significant difference between the prednisolone-treated group and the control group from the first to the fifth month. The histomorphometric profile of corticosteroid-induced osteoporosis was observed, in particular the lower bone volume and thinner and fewer trabecular plates. Mechanical tests are possible on rabbit vertebrae and showed a very significant difference in bone strength between the prednisolone-treated and control groups, and a good correlation between mechanical tests and histomorphometric or densitometric results. This bone corticosteroid model shows that vertebral compression tests are possible on rabbit lumbar vertebrae. It may contribute to a better evaluation of corticosteroid treatments.

The frequency of heterotopic ossification in neurological conditions averages 20-25 % with variations according to the type of neurological disease and presence or absence of coma. The most common sites are the hips, knees, shoulders, and elbows. Involvement of the hands is an exceedingly rare event of which two instances are reported herein. In both patients evidence of inflammation developed four months after a deep, prolonged coma. Swanneck deformity of the fingers occurred in one case. Juxtaarticular ossifications were seen on roentgenograms two months after the onset of symptoms. Both patients had heterotopic ossifications around the shoulders. Erythrocyte sedimentation rate and serum alkaline levels were elevated. Local injections effectively relieved pain in one patient.

The frequency of heterotopic ossification in neurological conditions averages 20-25% with variations according to the type of neurological disease and presence or absence of coma. The most common sites are the hips, knees, shoulders, and elbows. Involvement of the hands is an exceedingly rare event of which two instances are reported herein. In both patients evidence of inflammation developed four months after a deep, prolonged coma. Swanneck deformity of the fingers occurred in one case. Juxta-articular ossifications were seen on roentgenograms two months after the onset of symptoms. Both patients had heterotopic ossifications around the shoulders. Erythrocyte sedimentation rate and serum alkaline levels were elevated. Local injections effectively relieved pain in one patient.

While osteoporosis is characterized by a low bone mass there is a well-recognized overlap in bone mineral density (BMD) measurements between groups of subjects with and without vertebral fracture. To investigate whether differences in trabecular architecture may contribute to the presence or absence of fractures independent of the bone mass, fracture and nonfracture groups matched for age, gender, and BMD were assembled. Transiliac biopsies and corresponding lumbar spine BMD measurements from 31 women and 16 men with vertebral fracture were compared with those from 22 women and 11 men without fracture. Lumbar BMD (L1–4) was measured using a Hologic 2000 densitometer. The lumbar BMD was similar in women with and without fracture (0.63 g/cm3 ± 0.10 SD and 0.71 g/cm3 ± 0.17 SD, n.s.) and in men with and without fracture (0.72 g/cm3 ± 0.12 SD and 0.76 g/cm3 ± 0.17 SD, n.s.). Undecalcified iliac crest biopsy sections, 8 μm thick, were analyzed for remodeling variables and trabecular architecture using OsteoMeasure and TAS image analysis systems. No significant difference was found in either gender between fracture and nonfracture groups in percent bone volume (mean 10% in all groups), or in the wide range of remodeling and architectural variables measured, including the trabecular width, number, and separation, mean trabecular plate density and fractal dimension, as well as several indirect indices of connectivity including the node:terminus ratio, marrow star volume, and trabecular pattern factor. On the basis of this evidence it was concluded that there is no difference in the trabecular architecture between patients with crush fracture and controls when account is taken of bone mass. This suggests that microanatomical disruption is a predictable intrinsic feature of bone loss. However, there remains the possibility that the two-dimensional character of the structural deterioration measured indirectly is not sufficiently sensitive for the complex cancellous system. This is considered further in part II.