Impact assessment of multiple pressures on ecosystem services with a state and transition model: Application to Posidonia oceanica seagrass meadows.

A significant challenge in the integration of ecosystem services into decision-making processes lies in effectively capturing the dynamics of marine socio-ecological systems, including their evolutionary pathways, equilibrium states, and tipping points. This paper explores the evolutionary trajectories of a vital marine ecosystem endemic to the Mediterranean Sea: the Posidonia oceanica seagrass meadows, in response to various drivers of change. A state-and-transition model is employed to assess the ecosystem services provided by P. oceanica across different states defined by selected transitions, such as overfishing, fragmentation, pollution, and invasion by non-native species. To apply this model, scientific expertise is combined with field data generated using the Ecosystem-Based Quality Index to evaluate the conservation status of P. oceanica. This integrated approach allows for the representation of the ecosystem services offered by the meadows across different states, leveraging ecological data. The findings highlight the disproportionate impact on provisioning services, particularly sea urchins and commercial fish production, which suffer the most under various stressors. Notably, when these services decline to critical levels, the meadows cease to provide significant benefits. Finally, a synthesized representation is presented, merging ecological insights with monitoring data, offering a framework that is more accessible to stakeholders and decision-makers.

Minimally invasive treatment of displaced intra-articular calcaneal fractures using the balloon kyphoplasty technique: preliminary study.

BACKGROUND: The balloon kyphoplasty approach to the treatment of vertebral fractures can be adapted to achieve the reduction and cement stabilisation of intra-articular compression fractures at other sites, such as the calcaneus. PATIENTS AND METHOD: We studied six patients with a median follow-up of 12 months (range, 6-30 months). Fluoroscopy guidance was used to obtain optimal balloon positioning under the joint depression site. Reduction was achieved by expanding the balloon and stabilisation by injecting the cavity with resorbable tricalcium-phosphate cement in the younger patients and polymethyl-metacrylate cement in the two elderly patients with osteoporosis. No internal fixation was used. RESULTS: No intra-operative, postoperative, or delayed complications were recorded. Median hospital stay length was 4.5 days (range, 3-7 days). All the fractures healed within the usual timeframe, without loss of reduction. Median time to full weight-bearing ambulation was 52.5 days (range, 15-75 days). The functional outcomes correlated with the good anatomic results, with a median American Orthopaedic Foot and Ankle Society score of 87.0 (range, 86-97). DISCUSSION: This preliminary study shows that balloon reduction and cement fixation of intra-articular calcaneal fractures is easy to perform, reproducible, and devoid of specific complications. Good-quality reduction and stabilisation until fracture healing were achieved, and time to recovery of self-sufficiency was short, even in elderly patients with osteoporosis. These results support the use of this minimally invasive technique. LEVEL OF EVIDENCE: Level IV, retrospective study.

Progressive limitation of knee flexion secondary to an accessory quinticeps femoris muscle in a child: a case report and literature review.

We describe a symptomatic, progressive restriction of knee flexion due to an accessory quadriceps femoris in a nine-year-old girl. There was no history or findings of post-injection fibrosis, nor any obvious swelling of the affected quadriceps. At arthroscopy no intra-articular pathology was found. An accessory 'quinticeps femoris' was diagnosed by ultrasonography and MRI. Following excision of the muscle and tendon full flexion of the knee was regained and there was no recurrence of the contracture.

Acute osteomyelitis in children: the pathogenesis revisited?

PURPOSE OF THE STUDY: The present study reviews our experience of acute hematogenous osteomyelitis in 450 children over a period of 20 years from 1985 to 2004 at the Nouméa Territorial Hospital in New Caledonia. The objective was to formulate a new theory of the pathogenesis of this affection and to report our research on the disparity in the pathology between temperate countries and our own tropical Pacific area. PATIENT AND METHODS: Only children with an initially normal X-ray and showing symptoms for less than one week were included in the study. Subacute osteomyelitis, infant osteoarthritis and spinal and sacroiliac joint infections were all excluded. All children were treated according to a preestablished protocol including: clinical examination; blood tests; ultrasound, to determine the presence and size of the periosteal elevation and to exclude soft tissue abscess and frequent pyomyositis. Ultrasound was used in the decision to treat with antibiotics alone or with surgery. Computed Tomography was used for deep structures assessment and medical therapy guidance Surgery was limited to open drainage of the subperiosteal abscess only. Regular follow-up of outpatients was continued until normal blood test and X-ray results were achieved. RESULTS AND DISCUSSION: Four hundred and fifty children with a diagnosis of acute hematogenous osteomyelitis were identified, giving an average incidence of 22 new cases per year (range, 12-35). This incidence was two to five times as high as found in Europe. Fifty-three percent of our cases required surgical drainage (vs. 20 % in Europe). Ethnically, 60 % of the children were Melanesian and 20 % Polynesian (both represented less than 50 % of the local population). A similar incidence, about four times as high as in the population of European descent, was reported in Polynesians by our neighbors in New Zealand. The limbs were affected in 90 % of cases, and specifically lower limbs in 70 %. Multiple osseous lesions and systemic infection were recorded in 43 children (9.5 %). Blood cultures and surgical samples were positive in 80 % of cases, and otherwise negative. All the children were successfully treated, without chronic evolution or sequelae needing secondary surgery. The predominant microorganisms isolated were Staphylococcus aureus, in 81 % of cases, none of which were methicillin-resistant, and group A Streptococcus in 7.5 % of cases. A previous study of soft-tissue S. aureus infection showed the presence of Panton-Valentine Leukocidin (PVL) genes in 89 % of cases. These very infrequent genes are responsible for leukotoxic apoptosis, producing leukocidin, causing local acute aggressiveness. A parallel study, in progress for more than a year, is focusing on detecting PVL genes in S. aureus isolated from acute osteomyelitis: in the first nine children analyzed, PVL genes were likewise detected in 89 % of the S. aureus isolated, with no methicillin resistance. Ultrasonography allowed positive diagnosis in 64 % of cases on the day of admission and 84 % by the second day. Because of this very early presence of subperiosteal abscess at the beginning of the disease, and several other issues raised in the present study, we believe that Trueta's theory of acute osteomyelitis pathogenesis does not provide any logical explanation for our anatomoclinical observations. We believe that the primary focus of infection is in the osteoperiosteal area rather than under the growth plate in the metaphyseal bone. The term of Acute Osteo-Periostitis would therefore be much more suitable. A history of blunt trauma was found in 63 % of cases in the present series, and often reported in the literature. We speculate that two forms of infection fixation may develop: a local form, where bacteria carried by the blood stream reach a subperiosteal edema or hematoma secondary to blunt trauma, which is in our opinion the most frequent cause; and a general form, where fixation occurs as single or multifocal osteoperiostitis, and multivisceral locations in severe forms of septicemia. The disparity in this pathology between temperate countries and our own tropical Pacific area is certainly due to PVL-positive S. aureus and ethnic factors. The high prevalence of Melanesian and Polynesian patients confirms that they are at high risk of musculoskeletal infection in New Caledonia as in other Pacific countries, and it is possible that these ethnic groups are genetically susceptible to PVL-positive strains. LEVEL OF EVIDENCE: Level IV. Retrospective case series.

Fractures of the upper transthoracic cage.

We have reviewed our experience in managing 11 patients who sustained an indirect sternal fracture in combination with an upper thoracic spinal injury between 2003 and 2006. These fractures have previously been described as 'associated' fractures, but since the upper thorax is an anatomical entity composed of the upper thoracic spine, ribs and sternum joined together, we feel that the term 'fractures of the upper transthoracic cage' is a better description. These injuries are a challenge because they are unusual and easily overlooked. They require a systematic clinical and radiological examination to identify both lesions. This high-energy trauma gives severe devastating concomitant injuries and CT with contrast and reconstruction is essential after resuscitation to confirm the presence of all the lesions. The injury level occurs principally at T4-T5 and at the manubriosternal joint. These unstable fractures need early posterior stabilisation and fusion or, if treated conservatively, a very close follow-up.

[Epiphyseal distal torsion of the femur in osteoarthritic knees. A computed tomography study of 75 knees with medial arthrosis]. / La torsion épiphysaire distale du fémur dans le genou arthrosique. Etude tomodensitométrique de 75 genoux avec arthrose médiale.

PURPOSE OF THE STUDY: We used computed tomography (CT) to measure external torsion of the distal femur preoperatively in patients with osteoarthritic knees presenting genu varum in order to assess the correlation between femoral distal external torsion (FDET) and radiological or epidemiological data obtained during the general preoperative work-up. MATERIAL AND METHODS: Seventy-five knees were studied in 38 patients. Mean age was 70.4 years; there were 13 men and 25 women. The degree of external torsion of the distal femur was defined as the angle measured on the CT-scan between a line drawn tangent to the most posterior part of the condyles and the epidondylar line drawn from the lateral epicondyle to the most prominent point of the medial epicondyle. This angle was compared with the angle of the epiphyseal tibial varum measured on the anteroposterior radiograph and the overall deviation of the lower limb (HKA), and with the angle between the mechanical axis and the femoral shaft axis (HKS). We assessed the effect of gender and sex and looked for correlations between the FDET angle and measurements made on standard radiographs. Student's t test was used compare the FDET angle by sex and side. The alpha risk was set at 5%. RESULTS: The FDET angle measured a mean 5.36 +/- 1.87 degrees (0-9 degrees ). We did not find any correlation between the FDET angle and tibial epiphyseal varum or HKS angles. A weak statistical correlation between the FDET and the HKA angles had no clinical value. Finally, the FDET angle was not correlated with sex or side. DISCUSSION: Computed tomography provides reliable and reproducible measurements. Our work clearly demonstrated the wide interindividual variability of the FDET angle. We were unable to identify any measurement on standard radiographs allowing an indirect prediction of the FDET angle. CONCLUSION: Our findings suggest that measuring the FDET angle on preoperative CT-scans in candidates for total hip arthroplasty can be useful for adapting the angle of rotation for the femoral component to each patient.

[Ipsilateral hip and femoral shaft fractures: components of therapeutic choice]. / Fractures homolatérales de la diaphyse et du col fémoral: éléments de choix thérapeutique.

PURPOSE OF STUDY: Ten cases of ipsilateral hip and femoral shaft fractures were reviewed. MATERIAL AND METHODS: All patients were treated operatively for both fractures between 1988 and 1997 in Pitié Hospital. Five were treated with antegrade reamed intramedullary nails and cancellous screw fixation of the femoral neck, and 5 by long Gamma nail. The shaft fractures were fixed prior to definitive neck stabilization. RESULTS: Ipsilateral hip and femoral shaft fractures accounts for 5.6 p. 100 of the whole femoral shaft fractures registered in the same period. All cases occurred in young adults and resulted from high-energy impaction injuries. There were numerous associated injuries and all patients were polytrauma. The hip fracture was initially overlooked in 1 case without subsequent nonunion or avascular necrosis. At a mean follow-up examination of 22 months, two-thirds had a good result and one-third a fair or a poor result. Nonunion of the femoral neck occurred in one patient as a result of initial displacement and subsequent malreduction, while all shaft fractures united. DISCUSSION: X-ray films of the hip should be done in all cases of femoral shaft fracture in order to decrease the high incidence of missed femoral neck fractures in ipsilateral injuries of the femur. The results indicate that patients with ipsilateral fractures of the femoral neck and shaft can obtain good results when rigid anatomic stabilization of the femoral neck is performed. The femoral shaft fracture is given first priority and is reduced and immobilized with antegrade closed intramedullary nailing. The femoral neck fracture is then treated with cancellous screw fixation or compression screw with long Gamma nail. CONCLUSION: The authors recommend the use of a long Gamma nail to fix this dual fracture whenever possible.

[Prognostic value of hemodynamic results in the acute phase of myocardial infarction]. / Valeur pronostique des résultats hémodynamiques à la phase aiguë de l'infarctus du myocarde.

The prognostic value of right cardiac catheterization in the acute phase of myocardial infarction is presently well established. The objective of this study is to determine the best discriminating threshold of the pulmonary capillary pressure (PCP) on the one hand and the cardiac index on the other hand. 96 patients presenting an acute myocardial infarction were entered in the study. Six thresholds for each parameter were studied. The following results were obtained: there are important clinical and hemodynamic discrepancies, especially for severe cases. The cardiac index (CI) has a better prognostic value than the pulmonary capillary pressure. The threshold greater than 18 mmHg for PCP and less than 2.2 l/min for the cardiac index, proves to be the most discriminating (better sensitivity with better specificity: sensitivity 60 p. cent with specificity at 81 p. cent for PCP; sensitivity at 73 p. cent with specificity at 78 p. cent for CI). A combined analysis of the two parameters, associated to their best discriminating threshold enables to identify a class of high-risk patients presenting approximately an 80 p. cent mortality in a hospital environment. In spite of the development of non-invasive methods to evaluate the prognosis in the acute phase of myocardial infarction, the hemodynamic exploration remains the leading method for its evaluation.

Abnormal properties of skin fibroblasts from patients with breast cancer.

The growth properties of fibroblasts from the thoracic skin of patients with mammary cancers were compared to those of fibroblastic cultures from patients with benign lesions or having undergone surgery for non-neoplastic diseases. As expected, an inverse correlation was found between the doubling potential of fibroblasts in vitro and the donor's age for cells from patients with benign lesions; however no correlation, was found with cultures from cancer patients. Moreover, the latter group responded in an abnormal way to three biological parameters: anchorage dependence, colony formation on monolayers of normal human epithelial cells and saturation densities in overcrowded culture conditions. Skin fibroblasts from one patient with a benign lesion, whose mother had developed a breast cancer, displayed all the abnormal growth properties. Periodic controls of this patient resulted in the early detection of a carcinoma 3 years after the first operation for a benign microcystic lesion. Finally, we found that multiple subcultivations in overcrowded culture conditions cause the selection of a fibroblastic cell subset with greater growth potential which, in the cell strain tested, could invade foreign tissue in vitro.