A Late Pleistocene coastal ecosystem in French Guiana was hyperdiverse relative to today.

Warmer temperatures and higher sea level than today characterized the Last Interglacial interval [Pleistocene, 128 to 116 thousand years ago (ka)]. This period is a remarkable deep-time analog for temperature and sea-level conditions as projected for 2100 AD, yet there has been no evidence of fossil assemblages in the equatorial Atlantic. Here, we report foraminifer, metazoan (mollusks, bony fish, bryozoans, decapods, and sharks among others), and plant communities of coastal tropical marine and mangrove affinities, dating precisely from a ca. 130 to 115 ka time interval near the Equator, at Kourou, in French Guiana. These communities include ca. 230 recent species, some being endangered today and/or first recorded as fossils. The hyperdiverse Kourou mollusk assemblage suggests stronger affinities between Guianese and Caribbean coastal waters by the Last Interglacial than today, questioning the structuring role of the Amazon Plume on tropical Western Atlantic communities at the time. Grassland-dominated pollen, phytoliths, and charcoals from younger deposits in the same sections attest to a marine retreat and dryer conditions during the onset of the last glacial (ca. 110 to 50 ka), with a savanna-dominated landscape and episodes of fire. Charcoals from the last millennia suggest human presence in a mosaic of modern-like continental habitats. Our results provide key information about the ecology and biogeography of pristine Pleistocene tropical coastal ecosystems, especially relevant regarding the-widely anthropogenic-ongoing global warming.

Global diversity patterns of larger benthic foraminifera under future climate change.

Global warming threatens the viability of tropical coral reefs and associated marine calcifiers, including symbiont-bearing larger benthic foraminifera (LBF). The impacts of current climate change on LBF are debated because they were particularly diverse and abundant during past warm periods. Studies on the responses of selected LBF species to changing environmental conditions reveal varying results. Based on a comprehensive review of the scientific literature on LBF species occurrences, we applied species distribution modeling using Maxent to estimate present-day and future species richness patterns on a global scale for the time periods 2040-2050 and 2090-2100. For our future projections, we focus on Representative Concentration Pathway 6.0 from the Intergovernmental Panel on Climate Change, which projects mean surface temperature changes of +2.2°C by the year 2100. Our results suggest that species richness in the Central Indo-Pacific is two to three times higher than in the Bahamian ecoregion, which we have identified as the present-day center of LBF diversity in the Atlantic. Our future predictions project a dramatic temperature-driven decline in low-latitude species richness and an increasing widening bimodal latitudinal pattern of species diversity. While the central Indo-Pacific, now the stronghold of LBF diversity, is expected to be most pushed outside of the currently realized niches of most species, refugia may be largely preserved in the Atlantic. LBF species will face large-scale non-analogous climatic conditions compared to currently realized climate space in the near future, as reflected in the extensive areas of extrapolation, particularly in the Indo-Pacific. Our study supports hypotheses that species richness and biogeographic patterns of LBF will fundamentally change under future climate conditions, possibly initiating a faunal turnover by the late 21st century.

Controlled prospective study on ultrasound simulation training in fetal echocardiography: FESIM II.

PURPOSE: To analyze the learning curves of ultrasound novices in fetal echocardiography during structured simulation-based ultrasound training (SIM-UT) including a virtual, randomly moving fetus. METHODS: 11 medical students with minimal (< 10 h) prior obstetric ultrasound experience underwent 12 h of structured fetal echocardiography SIM-UT in individual hands-on sessions during a 6-week training program. Their learning progress was assessed with standardized tests after 2, 4, and 6 weeks of SIM-UT. Participants were asked to obtain 11 fetal echocardiography standard planes (in accordance with ISUOG and AHA guidelines) as quickly as possible. All tests were carried out under real life, examination-like conditions on a healthy, randomly moving fetus. Subsequently, we analyzed the rate of correctly obtained images and the total time to completion (TTC). As reference groups, 10 Ob/Gyn physicians (median of 750 previously performed Ob/Gyn scans) and 10 fetal echocardiography experts (median of 15,000 previously performed Ob/Gyn scans) were examined with the same standardized tests. RESULTS: The students showed a consistent and steady improvement of their ultrasound performance during the training program. After 2 weeks, they were able to obtain > 95% of the standard planes correctly. After 6 weeks, they were significantly faster than the physician group (p < 0.001) and no longer significantly slower than the expert group (p = 0.944). CONCLUSION: SIM-UT is highly effective to learn fetal echocardiography. Regarding the acquisition of the AHA/ISUOG fetal echocardiography standard planes, the students were able to reach the same skill level as the expert group within 6 weeks.

Controlled Prospective Study on the Use of Systematic Simulator-Based Training with a Virtual, Moving Fetus for Learning Second-Trimester Scan: FESIM III.

OBJECTIVES: To analyze the feasibility of structured ultrasound simulation training (SIM-UT) in teaching second-trimester ultrasound screening using a high-end simulator with a randomly moving fetus. METHODS: This was a prospective, controlled trial. A trial group of 11 medical students with minimal obstetric ultrasound experience underwent 12 hours of structured SIM-UT in individual hands-on sessions within 6 weeks. Learning progress was assessed with standardized tests. Performance after 2, 4, and 6 weeks of SIM-UT was compared with two reference groups ((A) Ob/Gyn residents and consultants, and (B) highly skilled DEGUM experts). Participants were asked to acquire 23 2nd trimester planes according to ISUOG guidelines in a realistic simulation B-mode with a randomly moving fetus as quickly as possible within a 30-minute time frame. All tests were analyzed regarding the rate of appropriately obtained images and the total time to completion (TTC). RESULTS: During the study, novices were able to improve their ultrasound skills significantly, reaching the physician level of the reference group (A) after 8 hours of training. After 12 hours of SIM-UT, the trial group performed significantly faster than the physician group (TTC: 621±189 vs. 1036±389 sec., p=0.011). Novices obtained 20 out of 23 2nd trimester standard planes without a significant time difference when compared to experts. TTC of the DEGUM reference group remained significantly faster (p<0.001) though. CONCLUSION: SIM-UT on a simulator with a virtual, randomly moving fetus is highly effective. Novices can obtain standard plane acquisition skills close to expert level within 12 hours of self-training.

Changes in acute and trauma hand surgery in the first Covid-19 lockdown in a German trauma center: a retrospective analysis of 338 cases.

INTRODUCTION: Although Covid-19 and especially lockdown periods have affected our everyday live, its impact on hand traumatology is under investigated. MATERIALS AND METHODS: We retrospectively analyzed all patients presenting at a FESSH accredited HTRC and level 1 trauma center in Germany during the Covid-19 lockdown period and an equivalent timeframe in 2019 regarding incidence of hand trauma, injury mechanism, type of injury and hand surgeries. RESULTS: 338 patients presented at our department with acute hand injuries. A significant reduction of work-related accidents was found during lockdown contrary to an increase of do-it-yourself related trauma. Although the incidence of hand trauma decreased during lockdown by 18%, the rate of hand surgery increased in absolute and relative numbers. CONCLUSIONS: Although Covid-19 has negatively impacting elective and semi-elective surgeries, acute hand surgery has gained in importance represented by a shift from work related to do-it-yourself trauma and an increased rate of surgical treatment. LEVEL OF EVIDENCE: IV (therapeutic).

[Resection arthroplasty for thumb basal joint arthritis]. / Die Resektionsarthroplastik bei Rhizarthrose.

Due to the crucial role of the thumb for gripping, osteoarthritis of the first carpometacarpal joint leads to a substantial impairment of hand function. There are effective nonoperative and joint-preserving surgical treatment options for early stages of the disease. In advanced cases, after exploiting conservative treatment, carpometacarpal thumb arthrodesis or arthroplasty may be indicated in selected cases but trapeziectomy with or without interposition or suspension constitutes the gold standard surgical procedure. This reliably provides favorable results, irrespective of the technique, with pain relief, good physical function, excellent patient global assessment and low complication rates.

[Fractures of the carpal bones without the scaphoid bone]. / Frakturen der Handwurzel ohne Os scaphoideum.

With the exception of the relatively frequent fractures of the scaphoid bone, isolated fractures of individual carpal bones are rare. Because these injuries are uncommon and because of the complex anatomy and function of the carpus, treatment of carpal bone fractures can be challenging. Carpal bone fractures generally occur in young, sports active and professional patients, can be easily overlooked in plain radiographs and are frequently associated with ligamentous instability, neurovascular injuries and tendon lesions. Small posttraumatic alterations of the precisely aligned carpal structure can cause chronic pain and functional impairment. Therefore, if a wrist fracture is suspected a thorough clinical examination and appropriate differentiated imaging is always necessary, at the end of which a fracture can be excluded or an appropriate conservative or surgical treatment is initiated, with the aim of restoration of carpal anatomy and function.

[Extensor tendon injuries of fingers in the region of the metacarpophalangeal joint (zone V)]. / Strecksehnenverletzungen der Finger im Bereich der Grundgelenke (Zone V).

Due to the exposed situation of the extension side of the metacarpophalangeal joint when the fingers are bent, injuries in this region are not uncommon. The extensor apparatus lies directly below the skin and the various parts can be easily injured. Due to the complex anatomical structure, the different clinical appearances and the various forms of treatment, injuries of the extensor tendons in the region of the metacarpophalangeal joint must be examined in a very differentiated manner. The not uncommonly occurring deviation phenomenon makes all injuries in zone V suspicious and special attention must be paid to them. The alarming multitude of revision surgeries with tenolysis, arthrolysis and restoration of the balance of extensor tendons or centering show that these operations are much more demanding than the way they are appreciated in the literature and by many surgeons (beginner's operation). The article presents the surgical treatment with suture techniques and reconstruction possibilities as well as the aftercare, in addition to the special anatomy and diagnostics.

Long-term functional outcome after dorsal capsular imbrication for post-traumatic dorsal instability of the distal radioulnar joint.

PURPOSE: The goal of this study was the assessment of long-term outcome of dorsal capsular imbrication of the distal radioulnar joint (DRUJ) in dorsal instability. METHODS: The study included ten patients (mean 38.7 years of age) with a mean follow-up time of 11.2 years (9.3 years to 14.3 years). Examination parameters included Disabilities of Arm, Shoulder, and Hand (DASH) questionnaire, modified Mayo Wrist Score (MMWS), determination of range of motion in comparison with the healthy extremity, pre- and post-operative pain level assessment, and examination of DRUJ stability. RESULTS: Eight of ten DRUJs proved to be stable after the above-mentioned follow-up. Mean MMWS was 92.5 (65-100; SD: 11.1). Mean DASH Score was 8.8 (0-60; SD: 18.4). Grip strength reached 93.5% of the contralateral unaffected hand. Range of motion did not differ significantly in comparison with the healthy contralateral extremity. Nine of ten patients regarded pain level reduction as excellent. Eight of ten patients regarded DRUJ stability as excellent after surgery. CONCLUSION: Dorsal capsular imbrication of the DRUJ is an efficacious surgical technique for post-traumatic dorsal instability in the long-term.

Distal radioulnar joint instability: current concepts of treatment.

Distal radioulnar joint (DRUJ) instability is often an underestimated or missed lesion which may entail fatal consequences. The triangular fibrocartilage complex is a biomechanically very important stabilizer of the DRUJ and guarantees unrestricted range of motion of the forearm. To detect DRUJ instability a systematic examination is of uppermost importance. The contralateral healthy arm will be used for comparison during clinical examination. X-rays are required to exclude osseous lesions or deformities. Computed tomography of both wrists in neutral forearm rotation, supination, and pronation may be necessary to verify DRUJ instability in ambiguous situations. Following a systematic clinical examination wrist and DRUJ arthroscopy detects lesions definitely. Tears of the distal radioulnar ligaments which entail DRUJ instability should be repaired preferably anatomically. Ulnar-sided ligament ruptures which cause instability are detected more often than radial-sided ones. Osseous ligament avulsions are mostly refixated osteosynthetically. Ligamentous tears of the distal radioulnar ligaments may be reconstructed using anchor suture or transosseous refixation. Secondary procedures such as tendon transplants are necessary for anatomical reconstruction in cases of unrepairable ligament tears.

[Secondary reconstruction of flexor tendons]. / Sekundäre Wiederherstellung von Beugesehnen.

The secondary reconstruction of flexor tendons is in most cases very demanding and tedious. The indications, selection of the correct surgical procedure, operative technique and further treatment have to be individually adjusted and are mostly very difficult. Due to the previous operations unpleasant surprises may occur intraoperatively, which must be recognized and treated by the surgeon. Nevertheless, a significant improvement of the function of the whole hand can be achieved for most patients, e.g. by a two-stage flexor tendon transplantation or other techniques described in this article.

Relationship Between Viremia and Specific Organ Damage in Ebola Patients: A Cohort Study.

Background: Pathogenesis of Ebola virus disease remains poorly understood. We used concomitant determination of routine laboratory biomarkers and Ebola viremia to explore the potential role of viral replication in specific organ damage. Methods: We recruited patients with detectable Ebola viremia admitted to the EMERGENCY Organizzazione Non Governativa Organizzazione Non Lucrativa di Utilità Sociale (ONG ONLUS) Ebola Treatment Center in Sierra Leone. Repeated measure of Ebola viremia, alanine aminotransferase (ALT), aspartate aminotransferase (AST), bilirubin, creatine phosphokinase (CPK), lactate dehydrogenase (LDH), activated prothrombin time (aPTT), international normalized ratio (INR), creatinine, and blood urea nitrogen (BUN) were recorded. Patients were followed up from admission until death or discharge. Results: One hundred patients (49 survivors and 51 nonsurvivors) were included in the analysis. Unadjusted analysis to compare survivors and nonsurvivors provided evidence that all biomarkers were significantly above the normal range and that the extent of these abnormalities was generally higher in nonsurvivors than in survivors. Multivariable mixed-effects models provided strong evidence for a biological gradient (suggestive of a direct role in organ damage) between the viremia levels and either ALT, AST, CPK LDH, aPTT, and INR. In contrast, no direct linear association was found between viremia and either creatinine, BUN, or bilirubin. Conclusions: This study provides evidence to support that Ebola virus may have a direct role in muscular damage and imbalance of the coagulation system. We did not find strong evidence suggestive of a direct role of Ebola virus in kidney damage. The role of the virus in liver damage remains unclear, but our evidence suggests that acute severe liver injury is not a typical feature of Ebola virus disease.

Functional outcome after endoscopic assisted release of the ulnar nerve for cubital tunnel syndrome: mid-to-long term results.

AIM OF THE STUDY: The aim of the study was to investigate functional and patient-rated outcome parameters after endoscopic assisted release of the ulnar nerve for cubital tunnel syndrome. METHODS: One hundred of 204 consecutive patients between 2006 and 2011 met the inclusion/exclusion criteria. Fifty-one of these patients were recruited and evaluated clinically and by questionnaire testing retrospectively after a mean follow-up of 82 months (range: 60-116). RESULTS: Neurological parameters (two-point-discrimination, application of Semmes-Weinstein monofilaments, Tinel's test), grip, and three-point pinch strength were not significantly different from the contralateral extremity at the time of examination, whereas key pinch strength was significantly weaker. Mean Disabilities of the Arm, Shoulder, and Hand score was 20.82. Patients' overall opinion was good/excellent for 78% of the study population. DISCUSSION: The examined surgical procedure proved to be as efficacious as open in-situ decompression regarding functional outcome with fewer post-operative complications. Regarding the results it might be postulated that grip strength and three-point pinch strength determination is not necessarily relevant for ulnar nerve evaluation. CONCLUSION: Endoscopic assisted release of the ulnar nerve is a reliable and safe treatment option for cubital tunnel syndrome with satisfactory mid-to-long term functional and patient-rated outcomes.

[Corrective osteotomy of the hand]. / Korrekturosteotomie an der Hand.

Fractures of fingers and metacarpals are among the most frequent injuries. Many fractures can be successfully treated conservatively. Nevertheless, various malformations, such as malrotation, spur development, bone shortening, deviation of the axis and combinations of these individual deformities may appear in the course of time. Corrective osteotomy can correct these deformities with clinically impaired function and improve/optimize hand function. Prerequisites for corrective osteotomy are a precise analysis of the deformity, precise osteotomy, exercise stable osteosynthesis and intensive follow-up treatment of the hand. Complications, such as implant failure, postoperative tendon and joint adhesions, joint contracture and nonunion are however possible.

Women with homozygous AT deficiency type II heparin-binding site (HBS) are at high risk of pregnancy loss and pregnancy complications.

Data regarding outcome and therapy of pregnancies in patients with homozygous antithrombin (AT) deficiency are very rare. We conducted a retrospective, descriptive investigation with emphasis on the obstetric history of eight women with homozygous AT deficiency heparin-binding site (HBS), who had at least one pregnancy. The aim of the study was to get a better insight into the outcome and identify suitable management procedures of pregnancy in this rare disease. All patients suffered from homozygous AT deficiency caused by the mutation c.391C>T p.Leu131Phe in the AT gene (SERPINC1). The women reported in total 23 pregnancies; one pregnancy was excluded because of induced abortion. We found that only seven out of the 22 analyzed pregnancies ended with a live infant, all of them were born preterm. Among the 15 negative outcomes, seven were early pregnancy losses and eight were intrauterine fetal deaths. We found no clear association between treatment protocols and outcome. Eight pregnancies were not treated at all; all of them ended with pregnancy loss. We conclude that homozygous AT deficiency HBS, a form of severe thrombophilia, is associated with high risk of pregnancy loss and preterm delivery. Rigorous anticoagulation and/or replacement of AT during pregnancy may improve the outcome.

A systematic review of pulse pressure variation and stroke volume variation to predict fluid responsiveness during cardiac and thoracic surgery.

This systematic review aims to summarize the published data on the reliability of pulse pressure variation (PPV) and stroke volume variation (SVV) to predict fluid responsiveness in an open-chest setting during cardio-thoracic surgery. The analysis included studies reporting receiver operating characteristics or correlation coefficients between PPV/SVV and change in any hemodynamic variables after a fluid challenge test in open-chest conditions. The literature search included seven studies. Increase in cardiac index and stroke volume index after a fluid challenge were the most adopted end-point variables. PPV and SVV showed similar area under the receiver operating characteristic curve values but high heterogeneity among studies. Cardiac and thoracic studies did not differ between PPV/SVV pooled area under the receiver operating characteristic curve. Studies exploring correlation between dynamic indices and end-point variable increase after fluid challenge showed conflicting results. The great heterogeneity between studies was due to small sample size and differences among protocol designs (different monitor devices, mechanical ventilation settings, fluid challenge methodologies, surgical incisions, and end-point variables). PPV and SVV seem to be inaccurate in predicting fluid responsiveness in an open-chest setting during cardio-thoracic surgery. Given the high heterogeneity of published data, more studies are needed to define the role of PPV/SVV in this context.

Feasibility, efficacy, and safety of ultrasound-guided axillary plexus blockade in pediatric patients with epidermolysis bullosa dystrophica.

BACKGROUND: In patients suffering from epidermolysis bullosa dystrophica (DEB), the most severe form of epidermolysis bullosa, trauma or friction cause separation of the skin from underlying tissue with consecutive painful blisters, scarifications, contractures, and pseudosyndactyly. To retain functionality of the hands surgical procedures are necessary. Anesthesia is challenging as difficult airways make general anesthesia risky. Regional anesthesia is considered controversial in patients with EB as accidental subcutaneous injections can cause severe blisters. As ultrasound-guided procedures became standard of care this might have changed however. AIM: In this case series, we describe feasibility, efficacy, and safety of ultrasound-guided plexus axillaris block in DEB patients undergoing hand surgery. METHOD: We performed a retrospective analysis of the charts of all children with DEB undergoing hand surgery under plexus axillaris block and sedation between 2009 and 2013 in our institution. RESULTS: Nineteen procedures in nine children were performed. Induction of anesthesia (securing monitoring, sedation, plexus block) took a mean time of 34 min. Perioperative analgesia was adequate in all procedures. No complications such as airway incidents, conversion to general anesthesia, movement during surgery, incomplete block, or formation of new blisters were seen. CONCLUSION: Ultrasound-guided plexus axillaris block in DEB patients undergoing hand surgery in our institution has been feasible, effective, and safe.

Biomechanical comparison of transosseous re-fixation of the deep fibres of the distal radioulnar ligaments versus deep and superficial fibres: a cadaver study.

PURPOSE: We hypothesized that the re-fixation of the deep and superficial fibres of the distal radioulnar ligaments provide improved stability compared to reconstruction of the deep fibres alone. METHODS: Fourteen fresh-frozen cadaver upper extremities were used for biomechanical testing. Transosseous re-fixation of the deep fibres of the distal radioulnar ligaments alone (single mattress suture group; n = 7) was compared to the transosseous re-attachment of the deep and superficial fibres (double mattress suture group; n = 7). Cyclic load application provoked palmar translation of the radius with respect to the rigidly affixed ulna. Creep, stiffness, and hysteresis were obtained from the load-deformation curves, respectively. Testing was done in neutral forearm rotation, 60° pronation, and 60° supination. RESULTS: The re-fixation techniques did not differ significantly regarding the viscoelastic parameters creep, hysteresis, and stiffness. Several significant differences of one cycle to the consecutive one within each re-fixation group could be detected especially for creep and hysteresis. No significant differences between the different forearm positions could be detected for each viscoelastic parameter. CONCLUSIONS: The re-fixation techniques did not differ significantly regarding creep, hysteresis, and stiffness. This means that the additional re-attachment of the superficial fibres may not provide greater stability to the DRUJ. Bearing in mind that the study was a cadaver examination with a limited number of specimens we may suppose that the re-attachment of the superficial fibres seem to be unnecessary. A gradual decline of creep and hysteresis from first to last loading-unloading cycle is to be expected and typical of ligaments which are viscoelastic.

The distal radial decompression osteotomy for ulnar impingement syndrome.

INTRODUCTION: The decompression of the distal radioulnar joint (DRUJ) is performed by ulnar translation of the radial shaft proximal to the sigmoid notch, i.e. detensioning of the distal part of the interosseous membrane (DIOM) while containment of the DRUJ is achieved by closed wedge osteotomy of the radius. The osteotomy shortens the radius which entails detensioning of the triangular fibrocartilage complex (TFCC). SURGICAL TECHNIQUE: Facilitating the modified Henry approach to the distal palmar radius a radial based wedge osteotomy is applied. The proximal osteotomy is proximal to the ulnar head and distal osteotomy is proximal to the sigmoid notch to prevent iatrogenic impingement. Ulnar translation of the radial shaft is performed to loosen the DIOM. The closed wedge osteotomy reduces radial inclination which will foster containment of the DRUJ. CONCLUSION: Distal radial decompression osteotomy of the DRUJ preserves DRUJ function while relieving painful impingement. Further surgical interventions are not compromised in case of failure.

Epidural analgesia does not influence anastomotic leakage incidence after open colorectal surgery for cancer: A retrospective study on 1,474 patients.

BACKGROUND: Anastomotic leakage is a major cause of morbidity after colorectal surgery. Epidural analgesia is the most effective method for postoperative pain relief after major abdominal surgery. Anyhow, its effect on anastomotic leakage rate is still controversial. This study aimed to compare epidural versus intravenous analgesia as risk factor for anastomotic leakage requiring reoperation in patients undergoing open colorectal surgery for cancer. METHODS: A retrospective study on 1,474 patients was performed. The Cox proportional hazards model was used to study the relation between primary and secondary factors of risk and anastomotic leakage occurrence within 30 days after elective operation. RESULTS: Overall 30-day anastomotic leakage requiring reoperation was 4.9% (95%CI: 3.8-6.0%). No difference in anastomotic leakage occurrence was observed between the epidural analgesia group and the intravenous analgesia group (Hazard ratio: 0.94; 95%CI: 0.53-1.67%; P = 0.8338). Females had a rate of anastomotic leakage 43% lower than males (P = 0.0301). The diverting stoma resulted to be protective for anastomotic leakage occurrence (P = 0.0052). AL significantly increased postoperative median length of stay but not in-hospital mortality. CONCLUSIONS: Epidural analgesia does not influence the AL risk after open colorectal surgery for cancer.