La craniectomie decompressive dans la prise en charge des traumatismes craniens graves avec signes radiologiques d’engagement cerebral.

Introduction La craniectomie décompressive peut- elle améliorer le pronostic des patients victimes d’un traumatisme crânien fermé grave avec engagement cérébral ? Objectif Le but de la présente étude était d’évaluer l’efficacité de la craniectomie décompressive dans la prise en charge du traumatisme crânien grave, isolé et fermé avec signes radiologiques d’engagement cérébral. Méthodes Il s’agissait d’une étude réalisée à l’Hôpital Général de Douala pendant 36 mois, de janvier 2007 à décembre 2009, incluant 13 patients victimes d’un traumatisme crânien grave, isolé et fermé, présentant les signes radiologiques d’engagement cérébral. La craniectomie décompressive était indiquée devant l’aggravation ou la persistance du tableau clinique et radiologique malgré le traitement médical conventionnel. Résultats Après deux à dix mois de suivi, l’évolution fut classée selon le score du coma évolutif ; "Glasgow outcome scale (GOS) score ". Dix patients (76, 93 %) ont évolué favorablement GOS (4-5).Un patient (07,69%) est resté végétatif GOS3. Deux décès (15,38%) ont été observé GOS1. Les principales complications étaient : une hydrocéphalie, une hernie cérébrale à travers le foramen de craniectomie, un abcès du cerveau et un état de mal convulsif. Conclusion La craniectomie décompressive est une méthode efficace pouvant améliorer le pronostic des patients victimes de traumatisme crânien grave avec signes radiologiques d’engagement cérébral.Mots clés : craniectomie-décompressive-engagement cérébral-traumatisme crânien

Origin of calcium in pedogenic carbonate nodules from silicate watersheds in the Far North Region of Cameroon: Respective contribution of in situ weathering source and dust input

Significant amounts of pedogenic Ca-carbonate nodules have been observed in the Far North Region of Cameroon in the carbonate-free watershed of the Mayo Tsanaga, thus a priori not favourable for carbonate nodules accumulations. These nodules are associated with a Clay-Rich Parent Material (CRPM), covering either a granitic (upstream) or a greenstone bedrock (downstream). In this peculiar context, the amount of pedogenic carbonate nodules represents large quantities of Ca and C. Therefore, determining the Ca sources for pedogenic carbonate nodules is a key point regarding the mechanisms leading to carbonate nodule precipitation and their role in the biogeochemical cycle of Ca. Three sites, two on granite and one on greenstone, were studied by combining Sr et Nd isotope systematics in order to assess the Ca sources of carbonate nodules and the origin of the CRPM associated with nodules. Carbonate nodules have a distinct Sr isotopic composition in each profile, pointing to the contribution of a local source for Ca. Sr isotopic compositions of plagioclases and carbonate nodules display a concomitant variation in each profile, indicating that plagioclases acted as a Sr, and thus Ca, source for the carbonate nodules. Nevertheless, carbonate nodules have a higher Sr isotopic signature than plagioclases, implying the contribution of another more radiogenic Sr source. Sr and Nd isotope data from the CRPM show that it is a mixture of weathered bedrock compounds and Saharan dust. This result highlights two other potential Sr and Ca sources: biotite and Saharan dust. Calculations of their respective contributions demonstrate that in situ weathering significantly adds to the Ca source of nodules. This result contrasts with many other studies from similar settings that highlight the importance of allochthonous - marine, aeolian - inputs. This conclusion points out that a substantial part of Ca is transferred from the local bedrock to the carbonate nodules. This mechanism seems to have been possible as peculiar edaphic conditions preserved the primary Ca sources, making in situ weathering a significant process for providing Ca

Complications per et postopératoires immédiates des arthrodèses lombaires et lombosacrées: Étude prospective d'une cohorte de 872 patients

Purpose of the study: Incidence of complications following lumbar or lumbosacral fusion is still an imprecise notion. The aim of this prospective observational study was to determine the frequency of intraoperative and early postoperative complications after this procedure and to analyze favoring factors. Material and methods: Twenty-one orthopedic units participated in this study which included 872 patients who underwent lumbar or lumbosacral fusion procedures involving the sector limited by L1 and S1. A minimum of 6 months follow-up was required for inclusion. Four types of complications were studied: general complications, infection, neurological and meningeal compications, mechanical problems. The following preoperative and intraoperative parameters were recorded: epidemiological and morphological data, history of lumbar spine surgery, comorbid conditions, indication for surgery, and technical aspects of the fusion. Two types of analysis were performed. The first was a descriptive analysis designed to determined the overall incidence of complications and the incidence of each type of complication. A multivariate analysis was then performed in order to determine factors influencing occurrence of complications. Results: Mean follow-up was 13 months, mean age of the cohort was 51 ± 15.5 years. Prior lumbar surgery was noted in 12% of the patients. A decompression procedure was associated in 40% of the patients due to lumbar stenosis. Posterolateral arthrodesis was used in 71% of the patients and 91% were instrumented. Most of the fusions were short, involving one or two levels. One or more intraoperative or early postoperative complications were observed in 200 patients (23%). The incidences of the four types of complications expressed in percent of the total cohort were 9,7%, 5,6%, 8.6%, and 3,6% for general, infectious, neurological and meningeal, and mechanical complications respectively. Three factors exhibited a significant correlation with occurrence of complications, irrespective of the type: excess weight, presence of several comorbid conditions, and extent of the zone of fusion. Conclusion: This study enabled a precise assessment of the incidence of complications subsequent to lumbar or lumbosacral fusion: 23%. The incidence of serious complications requiring a reoperation was 14.7%. This finding, together with the factors found to influence occurrence of these complications should be kept in mind when determining indications for lumbar or lumbosacral fusion

Principe de caractérisation des ondes isotropes de mesure de champ électrique en milieu équivalent aux tissus biologiques

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