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Ziel dieser Operation ist es, das mediale patellofemorale Ligament mittels distal gestieltem Quadricepssehnenstreifen zu ersetzen. Hierzu wird mit einem minimal invasiven Instrumentarium ein Quadricepssehnenstreifen uber einen kleinen superomedialen Zugang entnommen und dann nach medial zwischen zweiter und dritter Schicht des medialen Retinakulums geshuttelt. Einer der entscheidendsten Schritte ist das bildwandergestutzte Aufsuchen des Isometriepunkts, sodass physiologische Langenveranderungen und ein zufriedenstellendes postoperatives Ergebnis resultieren. Hiernach kann das Transplantat unter dosiertem Zug und Zentralisierung der Patella femoral fixiert werden. Eine fruhfunktionelle Nachbehandlung fuhrt hierbei zu einem guten Outcome.

Im Verlauf ihres Lebens erleidet mehr als die Halfte der Bevolkerung eine Fraktur, davon in 5–10 % mit gestorter oder ausbleibender Heilung. Die vorliegende Arbeit soll einen Uberblick uber die verschiedenen Moglichkeiten und Limitierungen einer adjuvanten Therapie zur Stimulation der Frakturheilung geben. Goldstandard bei gestorter Frakturheilung oder Pseudarthrose ist immer noch die Transplantation autologen Knochens. Daneben besteht die Moglichkeit einer physikalischen Stimulation sowie der direkten Beeinflussung der biologischen Prozesse wahrend der Frakturheilung durch osteogene Zellen oder Wachstumsfaktoren.

ZusammenfassungDie steigende Lebenserwartung wird zu einer Häufung von osteoporotisch bedingten Frakturen und Verletzungen von geriatrischen Patienten führen. Die häufigste Ursache von Frakturen sind dabei Stürze in Kombination mit Osteoporose. Durch spezielle Implantate konnte zwar eine Verbesserung der Möglichkeiten in der operativen Therapie erreicht werden, der Patient im hohen Lebensalter ist jedoch häufig multimorbide und benötigt eine interdisziplinäre Versorgung mit anschließender geriatrischer Rehabilitation zur vollständigen Wiedereingliederung. Art der Zusatzerkrankungen und zusätzlicher, altersbedingter Degeneration aller Organe beeinflussen die Indikation zum operativen Vorgehen und die Wahl des Behandlungsverfahrens nachhaltig. Osteoporotische Frakturen sind durch Mehrfragment- und Splitterbrüche, ausgeprägte metaphysäre Defektzonen sowie typische Lokalisationen wie an Wirbelsäule, proximalem Femur, distalem Radius sowie proximalem Humerus gekennzeichnet. Die Indikation zur operativen Stabilisierung von Frakturen bei Patienten im höheren Lebensalter muss der individuellen Erkrankungsschwere, dem spezifischen Verletzungsmuster und den Fähigkeiten des Patienten, die rehabilitativen Maßnahmen aktiv zu unterstützen, Rechnung tragen. Intramedulläre Verriegelungsnagelsysteme bieten wesentliche Vorteile gegenüber anderen speziellen Verfahren in Bezug auf ein geringeres Operationstrauma und eine frühere Belastungsstabilität und sind der „goldene Standard“ für schaft- und gelenknahe Frakturen. Winkelstabile Formplatten weisen ein geringeres Risiko einer sekundären Fraktur-Dislokation auf, können häufig über einen minimal invasiven Zugang nach gedeckter Reposition verankert werden und bieten vor allem bei periprothetischen Frakturen – ohne Lockerung des Implantats – eine dauerhafte Stabilisierung.

ZusammenfassungIn einem Kooperationsprojekt der AG Alterstraumatologie der Deutschen Gesellschaft für Unfallchirurgie und der Lohmann & Birkner Health Care Consulting GmbH mit dem Verband der Ersatzkassen e. V. (vdek) wurden der Arbeitsgemeinschaft Alterstraumatologie die relevanten Daten von ca. 23 Millionen Versicherten aus den Jahren 2002 bis 2004 zur Verfügung gestellt. Aus dem vorhandenen Datensatz wurden alle Krankenhausaufenthalte der Patienten ab einem Alter von 60 Jahren mit der Hauptdiagnose “hüftgelenksnahe Fraktur und keine weitere Verletzung” extrahiert und analysiert. Von 724 606 stationären Behandlungen fand sich in 68 929 (9,5 %) Fällen die Diagnose “hüftgelenknahe Fraktur” im Datensatz. Mit zunehmendem Alter zeigte sich eine deutliche Steigerung der Inzidenz von proximalen Femurfrakturen mit einem Maximum der Verletzungszahlen um das 82. Lebensjahr mit über 3000 Fällen. Die operative Behandlung der proximalen Femurfraktur erfolgte bei 49,5 % der Fälle mit einem gelenkerhaltenden stabilisierenden Verfahren (Osteosynthese – Schrauben – DHS – Nagelsysteme) und bei 48,6 % mit einer Endoprothese sowie bei 1,9 % mit einem sonstigen Verfahren. Für die osteosynthetischen Verfahren konnten kürzere Liegezeiten im Vergleich zu der prothetischen Versorgung nachgewiesen werden. Die Versorgung der proximalen Femurfraktur im Vergleich zu der tatsächlichen Bettenanzahl in Deutschland zeigt eine Mehrversorgung in den Kliniken mit 101 bis 600 Betten. Die Versorgung der proximalen Femurfrakturen, in Abhängigkeit von der Krankenhausgröße, zeigte eine überwiegende gleiche Verteilung der Operationsverfahren. Die Erlöse pro Fall der verschiedenen Osteosyntheseverfahren für die Krankenkassen wiesen keine wesentlichen Unterschiede auf und lagen bei ca. 6000 Euro (5815 Euro bis 6083 Euro). Die durchschnittlichen Erlöse für die Implantation einer Prothese lagen etwa 1000 Euro höher als die für Osteosyntheseverfahren (Hemiendoprothese: 7036 Euro, Totalendoprothese: 7201 Euro) und wiesen in den einzelnen Altersgruppen keine gravierenden Kostendifferenzen auf. Die akute Krankenhausmortalität stieg mit zunehmendem Alter bis auf 8,6 % in der Altersgruppe ab 85 Jahren an. Aufgrund der demografischen Entwicklung ist mit einer dramatischen Zunahme der Verletzungen in der Altersgruppe ab 85 Jahren von 74 % zu rechnen, insbesondere bis zum Jahre 2020 und von 350 % bis zum Jahre 2050.

The hydrophobic hydration of fullerenes in water is of significant interest as the most common Buckminsterfullerene (C60) is a mesoscale sphere; C60 also has potential in pharmaceutical and nanomaterial applications. We use an all-atom molecular dynamics simulation lasting hundreds of nanoseconds to determine the behavior of a single molecule of C60 in a periodic box of water, and compare this to methane. A C60 molecule does not induce drying at the surface; however, unlike a hard sphere methane, a hard sphere C60 solute does. This is due to a larger number of attractive Lennard-Jones interactions between the carbon atom centers in C60 and the surrounding waters. In these simulations, water is not uniformly arranged but rather adopts a range of orientations in the first hydration shell despite the spherical symmetry of both solutes. There is a clear effect of solute size on the orientation of the first hydration shell waters. There is a large increase in hydrogen-bonding contacts between waters in the C60 first hydration shell. There is also a disruption of hydrogen bonds between waters in the first and second hydration shells. Water molecules in the first hydration shell preferentially create triangular structures that minimize the net water dipole near the surface near both the methane and C60 surface, reducing the total energy of the system. Additionally, in the first and second hydration shells, the water dipoles are ordered to a distance of 8 Å from the solute surface. We conclude that, with a diameter of approximately 1 nm, C60 behaves as a large hydrophobic solute.

Most of the current scores and outcome prediction calculations in traumatology are based on the Abbreviated Injury Scale (AIS). However, this is not routinely used for documentation and coding of injuries in many countries, including Germany. Instead of the AIS, the International Classification of Diseases (ICD) is used. While the ICD functions as the basis for automated calculating of the diagnosis-related groups (DRG), no possibility of simple conversion of the 10th version of the ICD into AIS is available so far.The aim of this work is to develop and apply a methodology for simple conversion from ICD 10 to current AIS.The developed mapping procedure was based on a 1 : n relationship between trauma codes of ICD-10-GM and the codes of the AIS2005. Calculated ISS from the conversion codes were then compared with the actual ISS coding available from the clinical trauma documentation.It can be shown that, despite the considerable differences in the structure and systematic of both classification systems, an automated translation is technically possible.The preliminary result of the mapping suggests, however, that despite the technical feasibility of a reliable conversion and comparability of ICD 10 and AIS in the required quality is still questionable. An automated conversion is still possible and quality would possibly improve by inclusion of additional information.

OBJECTIVES Staphylococcus aureus osteomyelitis often develops to chronicity despite antimicrobial treatments that have been found to be susceptible in in vitro tests. The complex infection strategies of S. aureus, including host cell invasion and intracellular persistence via the formation of dynamic small colony variant (SCV) phenotypes, could be responsible for therapy-refractory infection courses. METHODS To analyse the efficacy of antibiotics in the acute and chronic stage of bone infections, we established long-term in vitro and in vivo osteomyelitis models. Antibiotics that were tested include β-lactams, fluoroquinolones, vancomycin, linezolid, daptomycin, fosfomycin, gentamicin, rifampicin and clindamycin. RESULTS Cell culture infection experiments revealed that all tested antibiotics reduced bacterial numbers within infected osteoblasts when treatment was started immediately, whereas some antibiotics lost their activity against intracellular persisting bacteria. Only rifampicin almost cleared infected osteoblasts in the acute and chronic stages. Furthermore, we detected that low concentrations of gentamicin, moxifloxacin and clindamycin enhanced the formation of SCVs, and these could promote chronic infections. Next, we treated a murine osteomyelitis model in the acute and chronic stages. Only rifampicin significantly reduced the bacterial load of bones in the acute phase, whereas cefuroxime and gentamicin were less effective and gentamicin strongly induced SCV formation. During chronicity none of the antimicrobial compounds tested showed a beneficial effect on bone deformation or reduced the numbers of persisting bacteria. CONCLUSIONS In all infection models rifampicin was most effective at reducing bacterial loads. In the chronic stage, particularly in the in vivo model, many tested compounds lost activity against persisting bacteria and some antibiotics even induced SCV formation.

Despite our growing knowledge about the mechanisms of fracture healing, about 5 to 10 % of all fractures show impaired healing or non-union formation. We have learned about the biomechanical requirements for adequate fracture healing, leading to sophisticated osteosynthesis techniques and specific implant systems. A poor "biology" is often made responsible for the failure of bone healing. However, the underlying "biological" mechanisms are multifactorial and poorly understood. There is a lack of knowledge and clinical evidence about specific biological factors which influence fracture healing. However, it is the responsibility of the medical practitioner to address all factors that could negatively influence fracture healing, while respecting general principles of conservative or operative fracture management. The current review aims to summarise patient-related factors that influence fracture healing including co-morbidities of the patient just as well as life style-related factors such as smoking, nutrition and alcohol consumption. It is hardly possible to prove a significant influence for each of these factors in clinical studies, because homogeneous cohorts and very high patient numbers would be needed. Nevertheless, a deeper knowledge about these factors potentially influencing fracture healing could help us to improve fracture healing and decrease the number of non-unions in our patients. Just as well as the surgeons performs precise incisions with a knife, a precise analysis and improvement of the "biology" are possible and recommended.

The reasons for delayed fracture healing or non-union formation are multifactorial. Mechanical factors are well known to influence the process of fracture healing. However, there is a lack of knowledge about the biological conditions that have to be achieved for adequate bone healing. Treatment of non-unions is still demanding and we have only poor options to stimulate the bone healing process. Therefore, it is important to optimise the biological conditions to avoid non-union formation. Beside patient-related factors, pharmacological drugs are able to impede or stimulate fracture healing. Especially geriatric patients show a pre-existing drug medication due to different co-morbidities. However, also younger patients are frequently treated with different drugs for infection prophylaxis, analgesia or thrombosis prophylaxis. The aim of the current review article is to give an overview about the influence of different pharmacological agents on the process of fracture healing. A deeper understanding of a drug-related influence on fracture healing could help the medical practitioner to optimise the general conditions for adequate fracture healing, i.e., by avoiding specific pharmacological agents. Vice versa some drugs could be used to stimulate fracture healing in the future.

In this communication, I discuss and improve the detection and modeling of the over-dispersion of winter storm occurrence using the example of Germany. For this purpose, the generalized Poisson distribution and information criterions for the model selection are introduced. Correct statistical model selection ensures the statistical significance of the model, including a possible over-dispersion. Moreover, I derive the relation between expectation and variance of a thinned inhomogeneous Poisson process. This is also applied to well detect the over-dispersion in winter storm data for Germany of Karremann et al. (2014).

To improve patient safety and quality in joint arthroplasty a certification of arthroplasty centers (EndoCert©) and a German arthroplasty register (EPRD) have been implemented. This should guarantee a long-term improvement in documentation of arthroplasty in the future. Although the stages of operations in elective and trauma-associated joint arthroplasty are comparable, the surgical preconditions are often quite different. As required by the German Society of Trauma Surgery (DGU) this study analyzed the current situation with respect to the proportion of fracture-associated joint arthroplasties among the total volume carried out in Germany.A uniform internet-based questionnaire was sent to all listed trauma centers in Germany by the central office of the DGU. In addition any information regarding hip joint arthroplasty in 2011 was collected from the Federal Statistical Office of Germany.The questionnaire was returned by 324 (47 %) out of 690 of the trauma centers contacted. A total of 34,135 total hip arthroplasties (THA) and 26,753 total knee arthroplasties (TKA) were carried out in 2011 by these clinics. The absolute numbers for total endoprosthesis replacement cited by the trauma centers were 5718 THAs and 3829 TKAs. According to the data from the Federal Statistical Office of Germany 131,966 hip fractures were registered in 2011, including 69,582 femoral neck fractures (patient age19 years) and 62,384 pertrochanteric fractures. From a total number of THAs of approximately 200,000 in Germany 47,695 (approximately 25 %) of these were associated with trauma.The data analyzed in this study and the results obtained from known literature sources demonstrate that THA is the most frequently performed procedure in trauma management of femoral neck fractures. Because of the ubiquitous and high incidence and the need for emergency treatment due to correlated risks and complications of delayed treatment, a high and standardized around the clock (24 h and 7 days a week) treatment option is mandatory. Long waiting times to treatment or transfer are inacceptable due to the increased mortality and complications.

The origins of the hydrophobic effect are widely thought to lie in structural changes of the water molecules surrounding a nonpolar solute. The spatial distribution functions of the water molecules surrounding benzene and cyclohexane computed previously from molecular dynamics simulations show a high density first hydration shell surrounding both solutes. In addition, benzene showed a strong preference for hydrogen bonding with two water molecules, one to each face of the benzene ring. The position data alone, however, do not describe the majority of orientational changes in the water molecules in the first hydration shells surrounding these solutes. In this paper, we measure the changes in orientation of the water molecules with respect to the solute through spatial orientation functions as well as radial/angular distribution functions. These data show that the water molecules hydrogen bonded to benzene have a strong orientation preference, whereas those around cyclohexane show a weaker tendency. In addition, the water–water interactions within and between the first two hydration shells were measured as a function of distance and “best” hydrogen bonding angle. Water molecules within the first hydration shell have increased hydrogen bonding structure; water molecules interacting across shell 1 and shell 2 have reduced hydrogen bonding structure.

The hydration structures of the hydrophobic solutes benzene and cyclohexane were investigated using molecular dynamics (MD) simulations of a single solute in water. Detailed, spatially resolved, three-dimensional maps of the density of the water O and H atoms surrounding either benzene or cyclohexane were generated from the simulation data. MD simulations were computed for each solute using either the ENCAD or GROMACS program package and one of five distinct water models: F3C, TIP3P, TIP4P, SPC, or SPC/E. For each solute, five 100 ns data sets, each representing a unique simulation condition, were analyzed. The water structure maps generated from the five data sets for each solute are remarkably similar. Our results show that water molecules in the first hydration shell around cyclohexane bind weakly. In contrast, water molecules bind more strongly and in a hydrogen-bonding orientation to the faces of the benzene ring. The high-resolution maps of the water structure surrounding benzene and cyclohexane presented in this paper reveal details of the positional preferences of water not resolved by other methods. They also show that the hydration structure at this level of detail is remarkably insensitive to the potential energy functions and simulation methods used.

Beim Morbus Bechterew, der ankylosierenden Spondylitis, handelt es sich um eine abakterielle rheumatoide Entzundung, die mit einer fortschreitenden Kyphosierung der Wirbelsaule einhergeht. Eine Osteoporose ist regelhaft nachweisbar. Aufgrund des erhohten Frakturrisikos konnen bereits Niedrigenergietraumen zu schwerwiegenden Lasionen der Wirbelsaule fuhren. Als Folge der veranderten Biomechanik resultieren nahezu ausschlieslich hoch instabile Verletzungen. Die Therapie der Wahl ist operativ, wobei die dorsale, multisegmentale Spondylodese die sicherste Art der Primarstabilisierung darstellt. Verbleibt ein Defekt der vorderen Saule, ist sekundar eine ventrale Gegenstabilisierung indiziert

Treatment of bone defects and non-unions frequently requires the transplantation of autologous bone. As an alternative, different kinds of bone substitutes have been used more often during the past years. These bone substitutes include synthetic materials, just as well as processed materials from human donors (allogen) or animals (xenogen). The relatively low hurdles in the approval process, compared to pharmaceutical drugs, have led to an almost unmanageable amount of different kinds of bone substitutes. Due to sparse clinical studies, evidence-based decisions for a specific product or a specific indication are hardly possible. Therefore, a deeper knowledge about basic properties of different bone substitutes is needed for a rational clinical decision. The present review aims to clarify the sometimes confusing nomenclature of bone substitutes and discuss their different biological properties. Generally, bone substitutes can be discriminated in osteogenic, osteoinductive and osteoconductive materials. The great majority of bone substitutes and especially synthetic materials serve as a matrix for bone growth and therefore possess mainly osteoconductive properties. The combination of these osteoconductive materials with osteogenic cells or osteoinductive growth factors, leads to composite materials with higher bone forming potential. Clinically, the quality and vitality of the recipient bone defect is of great importance. As a prerequisite for successful transplantation of bone substitutes or autologous bone, the recipient bone defect should be mechanically stable, free of infection with vital bone ends and intact soft tissue coverage. Bone defects in the spine, methaphyseal defects after trauma/tumour and diaphyseal segmental defects are typical indications for the application of bone substitutes. Unfortunately, the current literature does not allow concrete recommendations for specific bone substitutes or specific clinical indications. However, this review aims to discuss clinical benefits and limitations of bone substitutes for frequent indications to help clinicians in their decision making process.

The kinetic intermediate of RNase H is structured in a core region of the protein. To probe the role of this intermediate in the folding of RNase H, the folding kinetics of mutant proteins with altered native state stabilities were investigated. Mutations within the folding core destabilize the kinetic intermediate and slow refolding in a manner consistent with an obligatory intermediate model. Mutations outside of the folding core, however, do not affect the stability of the kinetic intermediate but do perturb the native state and transition state. These results indicate that interactions formed in the intermediate persist in the transition and native states and that RNase H folds through a hierarchical mechanism.

The ribonuclease H (RNase H) family of enzymes selectively degrades the RNA strand of RNA-DNA hybrids. This activity is essential for retroviruses such as HIV and resides in a domain of the larger reverse transcriptase molecule. RNase H from Escherichia coli is the best-characterized member of the family and serves as a model for structure/function studies. Despite having almost identical alpha + beta folds, the isolated domain from HIV is inactive and much less stable than the E. coli homolog. The HIV domain also shows increased disorder in its C-terminal regions (E-helix and His-containing loop). We investigated the importance of this region by studying a variant of E. coli RNase H lacking these elements (RNHdeltaE). Despite the elimination of 33 of 155 residues (including a complete helix), this C-terminal deletion mutant folds cooperatively as a subdomain. Surprisingly, this protein lacking residues near the active site retains weak Mn2+-dependent activity. A peptide corresponding to the deleted E-helix is helical in isolation and stimulates the activity of the deletion mutant in vitro. These results have implications for the catalytic mechanism of RNase H and drug design targeted to HIV reverse transcriptase.

Folding of ribonuclease HI from Escherichia coli populates a kinetic intermediate detectable by stopped-flow circular dichroism. Pulse labelling hydrogen exchange reveals that this intermediate consists of a structured core region of the protein, namely helices A and D and beta-strand 4. This kinetic intermediate resembles both the acid molten globule of ribonuclease HI and rarely populated, partially unfolded forms detected under native conditions. These results indicate that the first portion of ribonuclease HI to fold is the most thermodynamically stable region of the native state, and that folding of this protein follows a hierarchical process.

The incidence of proximal fractures of the femur will increase with the demographic change in the German population. Besides osteosynthesis, which in most cases of femoral neck, pertrochanteric and femoral head fracture is the method of choice, arthroplasty of the hip is likewise an established therapy. Indications are dislocated femoral neck fractures of the elderly. But there are good results for arthroplasty after proximal femoral fractures in younger active patients as well, when the fracture was not recognized or treated immediately. The outcome of hip arthroplasty after fracture is influenced by the elderly and unhealthy patient himself and the difficult planning and operation conditions due to fracture and its morphology. Most important for the best result are an interdisciplinary preparation of the patient and a well-planned surgery. In these cases common complications like thromboembolism, massive intraoperative blood loss and general infections like urinary tract infection can be reduced. For hip arthroplasty after fracture total hip replacement as well as hemiarthroplasty with bipolar prosthesis should be considered. The implant chosen and the implantation technique with or without bone cement has to be determined. Facts like the general state of health, biological age, level of activity and comorbidities should be taken into account appropriately.

Fragestellung: Biomechanische Evaluation der Kniegelenkskinematik nach Rekonstruktion des vorderen Kreuzbandes in Einzel- und Doppelbündeltechnik mit additiver Naht des Meniskus Methodik: Die Kinematik der intakten Kniegelenkes wurde in 12 humanen Präparaten mittels anteriorer tibialer[for full text, please go to the a.m. URL], Deutscher Kongress für Orthopädie und Unfallchirurgie (DKOU 2013)

Acute osteochondral lesions of the knee are injuries often caused by patella dislocations. In cases of negative standard x-rays magnetic resonance imaging (MRI) scans should be used to exclude these injuries, as even large fragments can escape visualization with x-rays. These lesions are strong indications for surgical intervention especially if refixation is considered. The intra-articular defect is visualized using arthroscopy and the dislocated fragment is retrieved entirely. Inspection of the fragment is performed ex situ to determine whether or not refixation should be performed. The refixation technique to be used for lesions in the femoro-patellar joint depends on fragment size and defect site. Current biodegradable implants have demonstrated good clinical results without the need for implant removal. The rehabilitation protocol should be individualized to the patient, size and site of the defect.

The incidence of pelvic fractures at 0.3-8% is low compared to all fractures. Nevertheless, the number of pelvic fractures in the elderly is increasing. Due to the increased age of the patient differences in trauma mechanism, fracture pattern and therapy occur. Most pelvic fractures in the elderly are caused by low-energy trauma. This makes it difficult to find the right diagnosis especially in insufficiency fracture of the pelvis. The time until the right treatment is started is prolonged significantly. Elderly patients who suffer from a high-energy fracture have a significantly higher risk of haemorrhage. At the same time emergency stabilisation of the pelvis using a C-clamp is dangerous due to the special fracture morphology with transiliac instabilities and the combination with osteoporosis. Low-energy trauma leads to simple fractures of the pubis, which often can be treated without operation. In these cases fractures of the dorsal pelvic ring need to be excluded using CT scan. Fracture of the dorsal part of the pelvic ring such as insufficiency fractures of the sacrum should be stabilized by 3D-guided percutaneous iliosacral screw fixation to reduce pain and allow early mobilisation.

Benchmarking is a very popular business process and meanwhile is used in research as well. The aim of the present study is to elucidate key numbers of German university trauma departments regarding research and teaching. The data set is based upon the monthly reports given by the administration in each university. As a result the study shows that only well-known parameters such as fund-raising and impact factors can be used to benchmark university-based trauma centers. The German federal system does not allow a nationwide benchmarking.

Bicycles are becoming increasingly popular. In Münster, a German town with a population of 273,000, bicycles were the main method of transportation in 2009, used more often (37.8%) than cars (36.4%). Each day in Münster, bicycles are used around 450,000 times. In 1982, they were only used around 270,000 times a day. However, the increased use of bicycles has also led to an increased number of bicycle accidents.Between February 2009 and January 2010, data on bicycle-accidents leading to injuries were collected by the Police of Münster and in all emergency units of the six hospitals in Münster. A systematic acquisition of technical data from the police and the medical data from the hospitals were combined anonymously. None of the forms contained personal data of patients involved, except for patient age and sex as well as time and place of bicycle accidents to match the questionnaires. The data were entered into a central database (MS Access for input/MySQL for data retrieval).2250 patients were included in this study. For each of these patients either a patient record or a hospital record or a police record or a combination of any of these different records existed in our database. In total, 1767 patients received medical treatment at a hospital and 484 people included in the study did not go to a hospital. Three fatalities occurred as a result of bicycle accidents. Considering reasons for hospital admission, traumatic brain injuries were the leading cause (25.7%). However, the largest resource consumption was attributed to fractures of the upper extremities (36.8%) and lower extremities (29.9%) with major surgery.Bicycle accidents occur more frequently than indicated by police records. The results of the Münster Bicycle Study have shown that the actual number of bicycle accidents exceeds the officially reported number by nearly two times. Since bicycle helmets cannot prevent accidents it is recommended not only to focus on helmet use as the only injury prevention method. Other factors, such as weather, pavement and default of traffic, roadworthiness of the bicycles or alcohol/drug abuse also affect the accident rates.

An efficient self-consistent 2-D Schrodinger/Poisson solver, including shifted periodic boundary conditions, is used to obtain the wavefunctions and energy levels in the quantum wires formed at the corners of periodic saw-tooth structures consisting of layers of Al 1− x Ga x As and GaAs materials. We find that the formation of a quantum wire at the corners of the GaAs layer is very sensitive to the physical parameters of the neighboring Al 1− x Ga x As layers. Simple potential models yield solutions which are qualitatively very different from self-consistent results. Electron population build-up in the GaAs region between the corners can be better controlled by using asymmetric doping. A direct consequence of the asymmetry is that in most cases there is electron confinement only at every other corner.

Fractures of the tibial head are severe injuries, characterized by enormous variety. Fractures can be classified into fractures of the tibial plateau, luxation fractures, and comminuted fractures. Due to the mechanism of injury luxation fractures are frequently associated with lesions of the menisci and intra- and extra-articular ligaments. Multiple factors can be etiologic for post-traumatic gonarthrosis: nonanatomic reduction of the joint surface, malalignment, and unaddressed associated injuries. Therefore in addition to diagnostic steps such as X-ray, CT scan, and MRI a sophisticated therapeutic regime is necessary. In cases with severely damaged soft tissue or unstable patients, the fracture should initially be reduced and fixed with an external fixator and the definite fixation should be performed in a second setting. Arthroscopically assisted treatment is reserved for fractures of the tibial eminence, crack fractures, and impression fractures. Comminuted and bilateral fractures can be addressed via different incisions. New locking plates with angular stability allow avoidance of bilateral plating in most situations. In specific cases such as compound fractures and for patients with low compliance, a hybrid fixator may be a well-chosen alternative.

Corresponding to the demographic development, fractures of the humerus, wrist, or hip will occur noticeably more often during the next four decades. The number of patients with hip fractures will increase to 170% of present-day numbers, and in the age group80 years to 250%. Trauma surgical departments should train their staff as well as adapt their workflows and ambient conditions to this demanding clientele to be prepared for these changes. For the elderly, a fracture may lead to need for permanent home care, which is why postoperative transfer to ambulatory care is especially important. The expected cost progression in traumatology of the elderly may be moderated by the conjunction of inpatient and ambulatory care, the utilization of synergies among the different service types, and by implementation of prophylaxis for osteoporosis and falls.

The structure of liquid water and its interaction with biological molecules is a very active area of experimental and theoretical research. The chemically complex surfaces of protein molecules alter the structure of the surrounding layer of hydrating water molecules. The dynamics of hydration water can be detected by a series of experimental techniques, which show that hydration waters typically have slower correlation times than water in bulk. Specific water-mediated interactions in protein complexes have been studied in detail, and these interactions have been incorporated into potential energy functions for protein folding and design. The subtle changes in the structure of hydration water have been investigated by theoretical studies.

The goal of this study was to evaluate the accuracy of CT-based computer-assisted pedicle screw insertion in the thoracic spine in patients with fractures, metastases, and spondylodiscitis compared to a conventional technique. A total of 324 pedicle screws were inserted in the thoracic spines of 85 patients: 211 screws were placed using a CT-based optoelectronic navigation system assisted by an image intensifier and 113 screws were placed with a conventional technique. Screw positions were evaluated with postoperative CT scans by an independent radiologist. In the computer-assisted group, 174 (82.5%) screws were found completely within their pedicles compared with 77 (68.1%) correctly placed screws in the conventional group ( p0.003). Despite use of the navigation system, 1.9% of the computer-assisted screws perforated the pedicle wall by more than 4 mm. The additional use of the image intensifier helped to identify the correct vertebral body and avoided cranial or caudal pedicle wall perforations.

We have employed natural guide star adaptive optics (AO) on the Keck II telescope to obtain near-infrared (H and K') images of three field galaxies, each of redshift greater than 0.5. These are among the highest-redshift non-active disk galaxies to be imaged with AO. Each of the galaxies was chosen because it had been observed previously with the Hubble Space Telescope (HST) Wide Field Planetary Camera 2 (WFPC2) by others. Our AO images in the near infrared (NIR) closely match both the depth and high spatial resolution of those optical data. Combining the archival V and I data with our new H and K' images potentially produces a long wavelength baseline at uniform resolution. The NIR data probe emission well longward of the 4000-Angstrom break at these redshifts, and provide stellar fluxes less contaminated by dust. We fit two-dimensional galaxy bulge-plus-disk models simultaneously in all bands, and compare stellar-population-synthesis modeling to the photometry of these separated components. This is an initial foray into combining HST and AO imaging to produce a high spatial-resolution multi-color dataset for a large sample of faint galaxies. Our pilot program shows that NIR AO images from large ground-based observatories, augmented by HST images in the optical, can in principle provide a powerful tool for the analysis of faint field galaxies. However, the AO data S/N will have to be increased, and AO PSFs need to be controlled more carefully than they were here., Comment: 22 pages, 16 Postscript figures. Accepted for publication in the ApJ Supplements

Verschiedene Studien konnten eine signifikante Verbesserung der Pedikelschrau-benlagen durch den Einsatz von Navigationssystemen zeigen. Daten uber die klinische Relevanz und Verhinderung von neurologischen Komplikationen durch die Navigation liegen jedoch nur bedingt vor. Ziel dieser Studie war es, die Haufigkeit von neurologischen Komplikationen und Revisionsoperationen bei Patienten mit navigierten und nicht navigierten Pedikelschrauben zu vergleichen.