[MRI of the axial skeleton for evaluation of prostate cancer extent in french Guyana]. / IRM du squelette axial pour le bilan du cancer de prostate en Guyane française.

INTRODUCTION: Spread evaluation of Prostate Cancer (PC) in French Guyana is bothered by the lack of bone scintigraphy. The availability of 4 MRI allows to develop alternatives using Axial Skeleton MRI (AS MRI). We report the related results. MATERIAL: AS MRI was done in patients with diagnosis of high risk PC: PSA>=10ng/ml and/or Gleason Score>=7 (predominant Gleason grade 4) and/or clinical T2b and/or T2b/T3 MRI and/or >50% positive biopsies. AS MRI was including spine, pelvis and skull assessement.The results were systematically compared to the clinical, biological and biopsy features. RESULTS: Amongst 163 AS MRI performed, 30 were positive and 133 negative. Of these 133 patients, 60 were submited to radical prostatectomy with or without lymphadenectomy. In these 133 patients with negative AS MRI, median PSA was 11ng/ml (1-51) and 27 (20,3%) had PSA>20ng/ml. In patients with positive AS MRI, only 1 had PSA<20ng/ml and predominant Gleason grade 3. CONCLUSION: Our study shows that AS MRI assessement is especially usefull in patients who are most likely to have bone metastasis that is to say those with PSA>20ng/ml and/or predominant Gleason grade 4. LEVEL OF EVIDENCE: 3.

[Skin ageing-General features of facial ageing and therapeutic choices]. / Vieillissement cutané ­ Vieillissement facial global : orientation thérapeutique.

Correction of cutaneous and facial ageing is the key reason for consultations in aesthetic dermatology. This demand on the part of patients, which has become a social phenomenon, has increased thanks to the remarkable progress made in nonsurgical and less invasive therapies such as lasers, botulinum toxin and fillers. But in order to optimise their use and to provide a personalised touch, since each face ages differently, an overall facial analysis, both static and dynamic, is essential. Indeed, ageing is obviously not restricted to skin but also concerns underlying tissue such as muscle, fat tissue and supporting bone. In this article, we provide a clinical and physiopathological analysis of the ageing of skin and of the various types of ageing, whether chronological, hormonal or environmental, and we examine the major role played by UV radiation, as well as tobacco smoke and, in certain cases, pollution. The description of cutaneous ageing covers not only the face, in which photoaging is the predominant factor, but also ageing of skin throughout the rest of the body. Next we describe the general modes of facial ageing for the subcutaneous structures, first those of the skin muscles, which compensate for their atrophy by means of permanent hypercontraction that result in dynamic wrinkles, then those of fat tissue in which ptosis can occur, coupled in some cases with atrophy and loss of the fullness and harmonious facial curves of youth, and those of supporting bone structures and preferential areas of resorption, which are also where the most pronounced ageing of soft tissue is discernible. The upper third, middle and lower third of the face do not age in the same way and the relevant methods of correction thus differ. Finally, we briefly discuss the therapeutic choices available, taking into account the generally extremely reasonable expectations of patients, who tend to seek moderate and natural rejuvenation in keeping with their personality, as well as the elimination of negative expressions associated with ageing, and who want neither a rigid face nor aesthetic cloning.

[Rational use of distraction osteogenesis in craniofacial surgery]. / Utilisation rationnelle de la distraction osseuse en chirurgie craniofaciale.

Distraction osteogenesis, initially developed by Ilizarov for limb, is the tissular extension caused by the progressive space of the osseous pieces following an osteotomy. Distraction is osteogenesic and histogenic. Twenty-five years ago, at the instigation of McCarthy, this technique was used to handle the craniofacial malformations in the various floors of the face : mandibular, mediofacial and cranial. The most wide-spread protocols respect a latency period from 0 to 7 days, a rhythm of distraction from 1 to 2mm a day in 2 at 4 times and a period of consolidation from 4 to 8 weeks. Distraction is the result of the inventiveness of the pioneers then the work to always adapt to the multiple complex clinical situations. The surgeon has to choose between internal or external materials allowing a mono- or multi-vectorial extension, in osseous and/or dental anchoring. The mandibular distraction is very effective for the treatment of the secondary obstructive syndromes in the unilateral or bilateral severe hypomandibular malformations. She also allows desobstruction of the superior airways within the framework of the mediofacial hypoplasies as well as the secondary treatment of the growth defects in cleft lips and palates. Finally, the distraction osteogenesis enhanced reliability of the fronto-facial advancement in early and secondary treatment of craniofaciosynostosis. This is a real support of the facial growth, which has to be included in a plan of global treatment.

Skeletal malformation in growing milk sheep.

INTRODUCTION: Two six-month old female Lacaune lambs with severe skeletal malformations of both front limbs were presented to the Department of Farm Animals, University of Zurich. The clinical examination showed alert animals with a high body weight and body condition score as well as a valgus deformation without pain or swelling. Radiographic examination showed severe irregularities in the epiphysial plate of the metacarpal bones in both lambs. Delayed growth in the lateral aspects of the physis was evident and resulted in valgus deformation. Nutritional causes were considered as the main reason for this presentation and a nutritional consultation was performed by the Institute of Animal Nutrition and Dietetics, University of Zurich. The estimated energy intake of these lambs was 65 % higher than the recommended maximum for growing sheep and the estimated vitamin D content of the diet was 71 % below the recommended allowance. Both animals were euthanized, and peripheral quantitative computed tomography (pQCT) was performed postmortem to measure total bone mineral density (BMD), trabecular bone mineral density (tBMD) and cortical bone mineral density (cBMD) of the left and right metatarsal bone of both animals. The BMD and the tBMD at 10 % of bone length were below the reference values and the BMD at 50 % was above the reference values. In addition, postmortem examination revealed a Salter-Harris-Typ-1 facture in the right caput humeri of one lamb. Histological evaluation showed defects in the articular cartilage with an eburnation in the metacarpal region and a disrupted area of columnar cartilage. This case report supports the fact that a high dietary energy intake leads to damage to the cartilage and the epiphyseal zone in sheep. In addition, insufficient dietary vitamin D intake contributed to the incomplete bone mineralization, as well as delayed growth and skeletal malformation.

INTRODUCTION: Deux agneaux Lacaune femelles de six mois présentant de graves malformations squelettiques des deux membres antérieurs ont été présentés au Département des animaux de rente de l'Université de Zurich. L'examen clinique a montré des animaux alertes avec un poids corporel et une note d'état corporel élevés ainsi qu'une déformation en valgus sans douleur ni gonflement. L'examen radiographique a montré de graves irrégularités dans la plaque épiphysaire des os métacarpiens chez les deux agnelles. Un retard de croissance du côté latéral de la physis était évident, entraînant une déformation en valgus. Des causes nutritionnelles ont été considérées comme étant la principale raison de cette situation et une consultation nutritionnelle a été effectuée par l'Institut de nutrition animale et de diététique de l'Université de Zurich. L'apport énergétique estimé de ces agneaux était supérieur de 65 % au maximum recommandé pour les moutons en croissance et la teneur estimée en vitamine D du régime alimentaire était inférieure de 71 % à l'apport recommandé. Les deux animaux ont été euthanasiés et une tomographie quantitative périphérique a été réalisée post mortem pour mesurer la densité minérale osseuse totale (DMO), la densité minérale osseuse trabéculaire (DMOt) et la densité minérale osseuse corticale (DMOc) des métatarses gauche et droit des deux animaux. La DMO et la DMOt à 10 % de la longueur de l'os étaient inférieures aux valeurs de référence et la DMO à 50 % était supérieure aux valeurs de référence. En outre, l'examen post-mortem a révélé une facture de Salter-Harris-Typ-1 dans le caput humeri droit d'un agneau. L'évaluation histologique a montré des défauts dans le cartilage articulaire avec une éburnation sousjacente dans la région métacarpienne et une zone de destruction du cartilage colonnaire. Ce rapport de cas confirme le fait qu'un apport énergétique alimentaire élevé entraîne des lésions du cartilage et de la zone épiphysaire chez les ovins. En outre, un apport alimentaire insuffisant en vitamine D a contribué à une minéralisation osseuse incomplète, ainsi qu'à un retard de croissance et à une malformation du squelette.

Moderate to vigorous physical activity and impact loading independently predict variance in bone strength at the tibia but not at the radius in children.

The objectives of this study were (i) to assess whether daily minutes of moderate to vigorous physical activity (MVPA) or vigorous physical activity (VPA) and impact counts (acceleration peaks ≥3.9g) independently predict variance in bone strength in children and youth and (ii) to estimate bone strength gain associated with increases in daily MVPA, VPA, or impact counts. We recorded 7-day activity of 49 participants (mean age 11.0 years, SD 1.7) using accelerometers and estimated radius and tibia bone strength using peripheral quantitative computed tomography. We used linear regression models adjusted for sex, body mass, and muscle area to address our objectives. Daily MVPA (mean 50 min, SD 23) and VPA (mean 17 min, SD 11) or impacts (mean 71 counts, SD 59) did not predict variance in radius strength. Daily VPA (ß = 0.24) predicted variance in tibia strength at the distal and shaft sites, and shaft strength was also predicted by MVPA (ß = 0.20) and impact counts (ß = 0.21). Our models estimated a 3%-6%, 4%, or 4%-11% gain in tibia strength after increasing daily MVPA by 10-20 min, VPA by 5 min, or impacts by 30-100 counts, respectively. In conclusion, daily minutes of MVPA or VPA and impact counts are independent predictors of tibia but not radius strength. Objective recording of activities associated with forearm bone strength and trials testing the efficacy of increasing daily MVPA, VPA, and related impacts on bone strength development in children and youth are warranted.

[Hand injuries in children]. / Généralités sur les traumatismes de la main de l'enfant.

The hand is one of the most commonly injured locations in children. In the young child, the ignorance of dangers may explain this frequency. In the older child, hand trauma is usually secondary to recreational sports. Most hand injuries in children are treated nonoperatively because of high remodeling potential. Surgical treatments are mandatory in case of open or unstable fracture, displaced intraarticular fractures and displaced phalangeal neck fractures. In phalangeal neck fractures, percutaneous treatment should be preferred. Finger stiffness and non-union are uncommon and are usually in relation with skin or vascular involvement. In case of physis fracture, clinical and radiological follow-up should monitor any growth problems.

Una propuesta teórica y conceptual para el modelado de la aparición de centros de osificación en diferentes tipos de huesos planos y largos / Une proposition théorique et conceptuelle pour le modelage des centres d'ossification dans différents types d'os plats et longs / Theoretical and conceptual proposal for appearance modeling of ossification centers in different types of flat and long bones

Se mostró un contexto de trabajo sobre el modelado de procesos de formación endocondral en cualquier tipo de osificación presente en los huesos del cuerpo. Siguiendo la suposición de que PTHrP (hormona paratiroidea) e Ihh (proteína Indian hedgehog) forman un bucle regulatorio bioquímico para el proceso endocondral, y BMP2 (proteína morfogenética de hueso-2) y Noggin en el intramembranoso, se implementaron los mecanismos regulatorios de este proceso. Para ello se utilizó un conjunto de ecuaciones de reacción-difusión ampliamente usadas en morfogénesis, en las que los factores bioquímicos se suponen secretados por células precursoras, mesenquimales y condrocitos, en el caso intramembranoso y endocondral, respectivamente. Se concluyó que la solución condujo a patrones denominados de Turing, que representan estos procesos de osificación de una forma muy aproximada(AU)

A work context on the modeling of endocondral formation process in any type of ossification present in the bones of the human body was shown. Assuming that PTHrP and Ihh form a biochemical regulatory loop for the endocondral process and BMP2 and Noggin for the intramembranous one, regulatory mechanisms for this formation process were implemented. For this purpose, a set of widely used diffusion reaction equations in morphogenesis were used in which the biochemical factors are supposed to be secreted by precursor cells, mesenchymal and chondrocytes in the case of intramembranous and chondroidal respectively. It was concluded that the solution led to the denominated Turing patterns which represent these ossification processes in a highly estimated form(AU)

Dans ce travail, un modelage du processus de formation endochondrale dans tout type d'ossification des os du corps est présenté. Supposant que PTHrP (peptide lié à l'hormone parathyroïdienne) et Ihh (protéine Indian Hedgehog) forment une boucle biochimique régulatrice pour le processus endochondral, et BMP2 (protéine morphogénétique osseuse-2) et Noggin pour le processus endomembraneux, des mécanismes régulateurs se produisent alors dans ce processus. C'est pourquoi, un groupe d'équations de réaction-diffusion largement utilisées dans la morphogenèse, où les facteurs biochimiques sont apparemment sécrétés par des cellules souches, mésenchymateuses et chondrocytes, a été utilisé. On a conclu que la solution a conduit à des modèles dits de Turing, représentant ces processus d'ossification de manière très similaire(AU)