Facteurs de risque fracturaire, nouveaux traitements: comment evolue la prise en charge de l'ostéoporose de la personne agée [Fracture risk, new treatments: how does the management of the osteoporosis of elderly change?]

Osteoporosis of elderly is a growing medical, economic and health-care problem. It is due to the increase of the life expectancy and the number of osteoporotic fractures. With the new Swiss-specific tool FRAX and the development of inpatients fracture trajectory, we can better identify patients with high risk of fracture. An appropriate treatment can be proposed more quickly. The follow-up of bone markers increases the treatment efficiency. With a better identification, treatment and follow-up of osteoporosis of elderly patients, we can ameliorate the patient's quality of life and decrease the number of osteoporotic fractures with a good cost-effectiveness ratio.

The fixation of locally beneficial alleles in a metapopulation.

Extinction, recolonization, and local adaptation are common in natural spatially structured populations. Understanding their effect upon genetic variation is important for systems such as genetically modified organism management or avoidance of drug resistance. Theoretical studies on the effect of extinction and recolonization upon genetic variance started appearing in the 1970s, but the role of local adaptation still has no good theoretical basis. Here we develop a model of a haploid species in a metapopulation in which a locally adapted beneficial allele is introduced. We study the effect of different spatial patterns of local adaptation, and different metapopulation dynamics, upon the fixation probability of the beneficial allele. Controlling for the average selection pressure, we find that a small area of positive selection can significantly increase the global probability of fixation. However, local adaptation becomes less important as extinction rate increases. Deme extinction and recolonization have a spatial smoothing effect that effectively reduces spatial variation in fitness.

Hip fracture incidence in the canton of Vaud, Switzerland, 1986-1991.

The objective of this study was to estimate the incidence of hip fracture in the canton of Vaud, Switzerland (total population 584 000), for the period 1986-1991 using routine hospital discharge data collected by the Cantonal Service of Statistical Research and Information (SCRIS). For the survey period, the estimated average annual crude incidence rate of hip fractures was 167 per 100 000 persons aged 20 or older (241 for women and 84 for men). For the population aged 50 years or older, the crude incidence rate was 388 per 100 000 persons (546 for women and 185 for men). The average annual age-specific rates rose exponentially by successive 5-year age groups. The median age of patients at the time of the fracture was 82 years in women and 74 years in men. There was no significant difference between the total number of cervical and trochanteric fractures. Between the ages of 20 and 84 years, the cumulative risk for a woman to be admitted to hospital with a hip fracture was twice that of a man (15.8% vs 7.8%). From 1986 to 1991, the age- and sex-adjusted incidence, like the ratio of cervical to trochanteric fractures, did not show any significant trend, although it was consistent with an increase in men (p=0.09). However, the annual number of fractures rose from 644 to 776, particularly among very aged men. The mean length of stay in the acute care hospital fell from 38 days in 1986 to 25 days in 1991. Finally, the comparison of these results with those obtained in 1986 for the same population from more exhaustive sources has confirmed the provision of a consistent, although overestimated, assessment of hip fracture incidence by means of these routine hospital statistics in the canton of Vaud, Switzerland.

Vertebral microarchitecture and fragility fracture in men: a TBS study.

INTRODUCTION: Although osteoporosis is considered a disease of women, 25% of the individuals with osteoporosis are men. BMD measurement by DXA is the gold standard used to diagnose osteoporosis and assess fracture risk. Nevertheless, BMD does not take into account alterations of microarchitecture. TBS is an index of bone microarchitecture extracted from the spine DXA. Previous studies have reported the ability of the spine TBS to predict osteoporotic fractures in women. This is the first case-controlled study in men to evaluate the potential diagnostic value of TBS as a complement to bone mineral density (BMD), by comparing men with and without fractures. METHODS: To be eligible for this study, subjects had to be non-Hispanic US white men aged 40 and older. Furthermore, subjects were excluded if they have or have had previously any treatment or illness that may influence bone metabolism. Fractured subjects were included if the presence of at least one fracture was confirmed. Cases were matched for age (±3 years) and BMD (±0.04 g/cm(2)) with three controls. BMD and TBS were first retrospectively evaluated at AP spine (L1-L4) with a Prodigy densitometer (GE-Lunar, Madison, USA) and TBS iNsight® (Med-Imaps, France) in Lausanne University Hospital blinded from clinical outcome. Inter-group comparisons were undertaken using Student's t-tests or Wilcoxon signed rank tests. Odds ratios were calculated per one standard deviation decrease as well as areas under the receiver operating curve (AUC). RESULTS: After applying inclusion/exclusion criteria, a group of 180 male subjects was obtained. This group consists of 45 fractured subjects (age=63.3±12.6 years, BMI=27.1±4.2 kg/m(2)) and 135 control subjects (age=62.9±11.9 years, BMI=26.7±3.9 kg/m(2)) matched for age (p=0.86) and BMD (p=0.20). A weak correlation was obtained between TBS and BMD and between TBS and BMI (r=0.27 and r=-0.28, respectively, p<0.01). Subjects with fracture have a significant lower TBS compared to control subjects (p=0.013), whereas no differences were obtained for BMI, height and weight (p>0.10). TBS OR per standard deviation is 1.55 [1.09-2.20] for all fracture type. When considering vertebral fracture only TBS OR reached 2.07 [1.14-3.74]. CONCLUSION: This study showed the potential use of TBS in men. TBS revealed a significant difference between fractured and age- and spine BMD-matched nonfractured subjects. These results are consistent with those previously reported on for men of other nationalities.

Fracture de la paroi mediale de l'orbite. A propos de 4 observations. [Fracture of the medial wall of the orbit. Apropos of 4 cases]

Fractures or the medial wall of the orbit are uncommon and clinical signs are often discreet. This report was focused on isolated fractures of the medial wall of the orbit. Blow-out trauma is usually the cause. In these cases the clinical signs ranged from simple ecchymosis to blindness by haematoma of the orbital cone. Computed tomography is a major tool for diagnosis and making therapeutic indications for these fractures. Treatment depends on the oculomotor involvements as measured by forced duction tests.

Isolated bilateral zygomatic arch fracture: an unusual pattern.

Isolated fractures of the zygomatic arch represent 5% to 14% of all zygomatic complex fractures. Bilateral isolated zygomatic arch fractures, which are defined as fractures of both zygomatic arches without any other facial fracture, are extremely rare. In this case report, we present a rare case of this facial fracture pattern.

Lateral condyle fracture of the humerus in children treated with bioabsorbable materials

Les fractures du condyle externe de l'enfant sont un traumatisme relativement fréquent qui survient le plus souvent chez l'enfant entre 5 et 15 ans. Elles sont classées en 3 grades : le grade 1 sans déplacement qui peuvent être traitées conservativement et les grades 2 (déplacées) et 3 (disloquées) qui nécessitent une prise en charge chirurgicale par réduction ouverte et embrochage. Le traitement traditionnel de ces fractures consistent en la mise en place de broches/vis métalliques qui doivent être retirées quelques semaines plus tard lors d'une seconde intervention. Depuis les années 90, des matériaux bio-résorbables à base d'acide polyglycoliques sont apparus en chirurgie orthopédique et traumatologique. En raison de la survenue de complications telles que réactions inflammatoires, formation de séromes ou ostéolyse, l'utilisation du matériel conventionnel a été préférée. Cependant, depuis quelques années, de nouveaux matériaux en acide polylactique sont apparus sur le marché. La période de résorption étant beaucoup plus lente, ces matériaux induisent des réactions beaucoup plus faibles, sans conséquences cliniques relevées jusqu'à présent. Chez l'adulte, de récentes études ont prouvés l'efficacité et l'absence d'effets secondaires liés à ces matériaux. Par contre, chez l'enfant, peu d'études à moyen terme ont été réalisées et l'impact sur l'os en croissance est peu connu, même si pour l'heure aucune conséquence clinique n'a été relevée. Dans le cadre de notre étude, nous avons comparé 2 groupes d'enfants traités pour des fractures du condyle externe du coude. Le premier groupe traité par du matériel conventionnel et le second par matériel résorbable. Les enfants ont tous étés suivis de manière très étroite durant la première année et la récupération clinique est similaire pour les 2 groupes. A 4 ans du traumatisme, les résultats fonctionnels sont identiques pour les 2 groupes et aucune complication liée au matériel résorbable n'a été mise en évidence. Par ailleurs, à 1 et 4 ans, les clichés radiologiques montrent l'absence de lésions liées au matériel résorbable. En conclusion, dans le cadre de notre travail nous avons pu montrer l'efficacité des matériaux résorbables dans la prise en charge des fractures du condyle externe du coude chez l'enfant. Ces matériaux permettent d'optimiser la prise en charge de ce type de fracture en prévenant un risque opératoire et anesthésique liés à une seconde intervention nécessaire au retrait du matériel d'ostéosynthèse conventionnel. Par ailleurs le coût lié à la prise en charge globale de ce type de fracture est moindre lors de l'utilisation de matériel résorbable.

Formaldehyde-fixation of platelets for flow cytometric measurement of phosphatidylserine exposure is feasible.

Strong platelet activation results in a redistribution of negatively charged phospholipids from the cytosolic to the outer leaflet of the cellular membrane. Annexin V has a high affinity to negatively charged phospholipids and can be used to identify procoagulant platelets. Formaldehyde fixation can cause factitious Annexin V binding. Our aim was to evaluate a method for fixing platelets avoiding additional Annexin V binding. We induced expression of negatively charged phospholipids on the surface of a fraction of platelets by combined activation with convulxin and thrombin in the presence of Annexin V-fluorescein isothiocyanate and calcium. Aliquots of resting and activated platelets were fixed with a low concentration, calcium-free formaldehyde solution. Both native platelets and fixed platelets were analyzed by flow cytometry immediately and after a 24-h storage at 4°C. We observed that the percentage of Annexin V positive resting platelets ranged from 1.5 to 9.3% for the native samples and from 0.4 to 12.8% for the fixed samples (P=0.706, paired t-test). The amount of Annexin V positive convulxin/thrombin activated platelets varied from 12.9 to 35.4% without fixation and from 15.3 to 36.3% after formalin fixation (P=0.450). After a 24-h storage at 4°C, Annexin V positive platelets significantly increased both in the resting and in the convulxin/thrombin activated samples of native platelets (both P<0.001), while results for formalin fixed platelets did not differ from baseline values (P=0.318 for resting fixed platelets; P=0.673 for activated fixed platelets). We conclude that platelet fixation with a low concentration, calcium-free formaldehyde solution does not alter the proportion of Annexin V positive platelets. This method can be used to investigate properties of procoagulant platelets by multicolor flow-cytometric analysis requiring fixation steps.

Prédiction de la fracture vertébrale: pouvoir discriminant de l'IMC, de la DMO, du TBS, du FRAX, seuls ou combinés. L'étude OsteoLaus.

Introduction. - L'ostéoporose est caractérisée par une diminution de la DMO et une altération de la microarchitecture (MA). La MA est évaluable en routine clinique par la mesure du Trabecular Bone Score (TBS), par simple ré-analyse de l'image lombaire de la DMO. Le TBS a démontré sa valeur diagnostique et pronostique, partiellement indépendante des FRC et le la DMO. Le but de la cohorte OsteoLaus est de combiner en routine clinique les FRC et les informations données par la DXA (DMO, TBS, VFA) et FRAX pour mieux identifier les femmes à risque de fracture. Matériels et Méthodes. - Dans la cohorte OsteoLaus (1 500 femmes, 50 à 80 ans, Lausanne, Suisse) les FRC, la DMO lombaire et de la hanche, l'IVA, le TBS et le FRAX sont relevés. La sensibilité et la spécificité des différents outils pour prédire les fractures vertébrales (FxV) de grade 2/3 ont été calculées. Résultats. - Nous avons inclus 451 femmes : âge 67,4 ± 6,7 ans, IMC 26,1 ± 4,6, DMO lombaire 0,943 ± 0,168 (T-score -1,4 SD), TBS 1,271 ± 0,103. La corrélation entre DMO et TBS est faible (r2 = 0,16). La prévalence des FxV 2/3 est de 9,3 %. Conclusion. - L'IMC a un mauvais pouvoir discriminant dans notre cohorte. Ces résultats préliminaires confirment l'indépendance partielle entre le TBS et la DMO. Une approche combinant TBS et FRAX semble être le meilleur compromis en termes de sensibilité/spécificité pour identifier les femmes avec une FxV 2/3 prévalente qui aurait pu être mal classifiée par la DMO ou le TBS ou le FRAX seuls.

Traumatic hernia of the abdominal wall after pelvic and acetabular fracture: a case report.

Traumatic hernia of the abdominal wall is a rare and easily missed injury in the presence of major pelvic and abdominal lesions. We present a radiographically documented case of combined pelvic and acetabular fracture with a major contralateral traumatic hernia with avulsion of the internal oblique, the external oblique and the transverse abdominal muscles diagnosed four months after the initial trauma. To our knowledge no similar case has been described in the current literature.

Fracture ostéoporotique chez les femmes ménopausées: l'alendronate réduit le risque. [Osteoporotic fracture in menopausal women: alendronate reduces the risk]

Cette rubrique présente les résultats d'une revue systématique publiée par la Collaboration Cochrane dans la Cochrane Library au premier trimestre 2008 (www.cochrane.org/). Volontairement limité à un champ de recherche circonscrit, cet article reflète l'état actuel des connaissances de ce domaine. Il ne s'agit donc pas de recommandations pour guider la prise en charge d'une problématique clinique considérée dans sa globalité (guidelines).

Seeds enriched with phosphorus and molybdenum improve the contribution of biological nitrogen fixation to common bean as estimated by 15n isotope dilution

Seeds with a high concentration of P or Mo can improve the growth and N accumulation of the common bean (Phaseolus vulgaris L.), but the effect of enriched seeds on biological N2 fixation has not been established yet. This study aimed to evaluate the effect of seeds enriched with P and Mo on growth and biological N2 fixation of the common bean by the 15N isotope dilution technique. An experiment was carried out in pots in a 2 x 3 x 2 x 2 factorial design in randomized blocks with four replications, comprising two levels of soil applied P (0 and 80 mg kg-1), three N sources (without N, inoculated with rhizobia, and mineral N), two seed P concentrations (low and high), and two seed Mo concentrations (low and high). Non-nodulating bean and sorghum were used as non-fixing crops. The substrate was 5.0 kg of a Red Latosol (Oxisol) previously enriched with 15N and mixed with 5.0 kg of sand. Plants were harvested 41 days after emergence. Seeds with high P concentration increased the growth and N in shoots, particularly in inoculated plants at lower applied P levels. Inoculated plants raised from high P seeds showed improved nodulation at both soil P levels. Higher soil P levels increased the percentage of N derived from the atmosphere (%Ndfa) in bean leaves. Inoculation with the selected strains increased the %Ndfa. High seed P increased the %Ndfa in inoculated plants at lower soil P levels. High seed Mo increased the %Ndfa at lower soil P levels in plants that did not receive inoculation or mineral N. It is concluded that high seed P concentration increases the growth, N accumulation and the contribution of the biological N2 fixation in the common bean, particularly in inoculated plants grown at lower soil P availability.