Displaced femoral neck fractures comprise more than a third of all hip fractures. There is controversy as to the optimal treatment. Despite attempts to improve the methods for internal fixation, complication rates have been almost unchanged: 20-40% non-union and late segmental collapse in another 10-20%. Internal fixation has been the preferred treatment in Scandinavia, whereas primary hemi- or total arthroplasty have been more prevalent in the rest of Europe and North America. In this study, patients 75 years or older, including those with mental impairment, were randomized to either internal fixation or cemented primary total hip arthroplasty (THA). A total of 146 hips in 143 patients were followed for two years. After one year 23% had died, and after two years 29%. Mortality was about the same in both groups. The accumulated mortality was pronounced among the mentally impaired patients. In the internal fixation group, 44% underwent further surgery. In the THA group, 18% dislocated. The dislocation rate was higher for the mentally impaired patients. The Harris hip scores were higher in the THA group, whereas pain was more common in the internal fixation group. The first 50 patients in each treatment group were studied concerning heterotopic ossification (HO), a well-known complication after THA. The incidence of HO in the THA group was similar to what is found after THA due to osteoarthritis. However, only 1/39 developed severe symptoms. A subgroup of 100 patients was included in a study concerning nutritional status and functional capacity using the Modified Norton scale, Katz index of ADL and a questionnaire measuring instrumental activities of daily living. The THA group fared better concerning weight change over time, locomotion and pain. The nutritional intervention did not show any measurable effects. All patients were followed until two years postoperatively and all fracturerelated hospital costs, including reoperations, were calculated. We found no difference in total costs between the treatment groups. Costs to the municipality were calculated comparing the baseline cost before surgery with the average cost per month during the first postoperative year. No difference was found between the treatment groups. On the basis of our results, we recommend arthroplasty for patients in this age group with normal mental function and high functional demands.

The intent of this thesis is to contribute to the understanding of the origin of fractures in rock. The man-made fracturing from engineering activities in crystalline rock as well as the fracturing induced by the natural process of meteorite impacts is studied by means of various characterization methods. In contrast to engineering induced rock fracturing, where the goal usually is to minimize rock damage, meteorite impacts cause abundant fracturing in the surrounding bedrock. In a rock mass the interactions of fractures on the microscopic scale (mm-cm scale) influence fractures on the mesoscopic scale (dm-m scale) as well as the interaction of the mesocopic fractures influencing fractures on the macroscopic scale (m-km scale). Thus, among several methods used on different scales, two characterization tools have been developed further. This investigation ranges from the investigation of micro-fracturing in ultra-brittle rock on laboratory scale to the remote sensing of fractures in large scale structures, such as meteorite impacts. On the microscopic scale, the role of fractures pre-existing to the laboratory testing is observed to affect the development of new fractures. On the mesoscopic scale, the evaluation of the geometric information from 3D-laser scanning has been further developed for the characterisation of fractures from tunnelling and to evaluate the efficiency of the tunnel blasting technique in crystalline rock. By combining information on: i) the overbreak and underbreak; ii) the orientation and visibility of blasting drillholes and; iii) the natural and blasting fractures in three dimensions; a analysis of the rock mass can be made. This analysis of the rock mass is much deeper than usually obtained in rock engineering for site characterization in relation to the blasting technique can be obtained based on the new data acquisition. Finally, the estimation of fracturing in and around two meteorite impact structures has been used to reach a deeper understanding of the relation between fracture, their water content and the electric properties of the rock mass. A correlation between electric resistivity and fracture frequency in highly fractured crystalline rock has been developed and applied to potential impact crater structures. The results presented in this thesis enables more accurate modelling of rock fractures, both supporting rock engineering design and interpretation of meteorite impact phenomena. / QC 20100709

The presence of fractures, joints and karst features within rock strongly influence the hydraulic and mechanical behavior of a rock mass, and there is a strong desire to characterize these features in a noninvasive manner, such as by using ground penetrating radar (GPR). These features can alter the incident waveform and polarization of the GPR signal depending on the aperture, fill and orientation of the features. The GPR methods developed here focus on changes in waveform, polarization or texture that can improve the detection and discrimination of these features within rock bodies. These new methods are utilized to better understand the interaction of an invasive shrub, Juniperus ashei, with subsurface flow conduits at an ecohydrologic experimentation plot situated on the limestone of the Edwards Aquifer, central Texas. First, a coherency algorithm is developed for polarimetric GPR that uses the largest eigenvalue of a scattering matrix in the calculation of coherence. This coherency is sensitive to waveshape and unbiased by the polarization of the GPR antennas, and it shows improvement over scalar coherency in detection of possible conduits in the plot data. Second, a method is described for full-waveform inversion of transmission data to quantitatively determine fracture aperture and electromagnetic properties of the fill, based on a thin-layer model. This inversion method is validated on synthetic data, and the results from field data at the experimentation plot show consistency with the reflection data. Finally, growing hierarchical self-organizing maps (GHSOM) are applied to the GPR data to discover new patterns indicative of subsurface features, without representative examples. The GHSOMs are able to distinguish patterns indicating soil filled cavities within the limestone. Using these methods, locations of soil filled cavities and the dominant flow conduits were indentified. This information helps to reconcile previous hydrologic experiments conducted at the site. Additionally, the GPR and hydrologic experiments suggests that Juniperus ashei significantly impacts infiltration by redirecting flow towards its roots occupying conduits and soil bodies within the rock. This research demonstrates that GPR provides a noninvasive tool that can improve future subsurface experimentation.

Diss. (sammanfattning) Umeå : Umeå universitet, 2009. / Härtill 4 uppsatser. Även tryckt utgåva.

This study provides new insights on the mechanisms that controlled the development of solution-enhanced fractures and suprastratal deformation associated with the Mississippian Madison Sequence IV evaporite paleokarst complex. Based on detailed field mapping utilizing LiDAR, GPS, and field observations, we document a paleostructural high (oriented 145º) associated with the Ancestral Rockies uplift within the study area. One hundred twenty-one sediment-filled, solution-enhanced fractures within the Seq. IV cave roof were mapped and characterized by their dominant fill type (Amsden or Madison) and vertical extent. Spatial analysis reveals minimum spacing of these features occurs in areas uplifted during the Late Paleozoic suggesting a link between paleostructural position and solution feature spacing. Shape analysis of these solution features also supports structural position during the Late Paleozoic acted as a dominant control on fracture morphology: (1) downward tapering and fully penetrative features concentrate in areas that experienced uplift; (2) upward tapering concentrate in areas that were undeformed. Mapping of Seq. IV cave roof strata demonstrates vertical collapse variability exceeds 22 m and fault intensity increases in areas of increased collapse. These findings have significant implications for prediction and characterization of solution-enhanced fractures and suprastratal deformation within evaporite paleokarst systems. / text

An appreciation of the extent of syndepositional fracturing, faulting, and cementation of carbonate platform margins is essential to understanding the role of early diagenesis and compaction in margin deformation. This study uses integrated lidar and outcrop data along the Capitan Reef from an area encompassing the mouths of both Rattlesnake and Walnut Canyons. Mapping geomorphic expressions of syndepositional faults and fractures at multiple scales of observation was the main approach to delineating zones of syndepositional fractures. Ridge- groove couplets visible in exposures of the Capitan Reef throughout the Guadalupe Mountains were targeted because the ability to identify these as signs of syndepositional fracture development would have implications for the entire reef complex. Results show that these ridgegroove couplets are the product of differential weathering of syndepositional as well as burial-related fractures. Recessive grooves have an average syndepositional fracture spacing of ~13 m whereas ridges have a spacing of ~33 m. vi Smaller (~5-20 m-wide) scale erosional lineaments common in the study area and mappable on airborne lidar are formed by differential erosion of planes of syndepositional faults. Maps of these fault lineaments on the lidar show that syndepositional faults extend laterally for 300 m - 2000 m and relay near the terminations of the faults at each end. Faults can be further grouped into fault systems consisting of sets of faults connected by fault relays that extend for at least the entire length (~12 km) of the study area. Although vertical displacement along faults is typically less than 11 m, syndepositional faults result in changes in structural dip domain of 1-6 degrees across an individual fault. Even smaller erosional lineaments (10 cm-1 m) are visible on the airborne lidar that form as a result of differential erosion of individual fractures. Larger fractures (> 20 cm) can be reliably mapped on the lidar, but smaller features (< 20 cm) cannot be reliably mapped with currently available data and can only be captured using field studies. Fracture fill types are heterogeneous along strike as shown by comparisons of field study locations. Siliciclastic-dominated fills are likely sourced from overlying siliciclastic units of the shelf, which, in this area, were from the Ocotillo Siltstone. These silt-filled fractures are broadly distributed, indicating preferential development and infill of syndepositional fractures during the deposition of the Ocotillo Siltstone in the G27/28 high-frequency sequences. Development of early fractures is also shown to have been influenced by mechanical stratigraphy with changes in fracture spacing between massive to thick-bedded shelf-margin (~17 m fracture spacing) and outer-shelf facies tracts versus thin-bedded outer-shelf and shelf-crest (~28 m fracture spacing). Ultimately, this study demonstrated that the Capitan shelf margin was ubiquitously overprinted by syndepositional fracturing and faulting and that this nearsurface structural modification influenced early diagenetic patterns and internal vii sedimentation throughout the reef margin. Before this study, the extent and nature of syndepositional fracture/fault development within the margin were largely unquantified. Here, by integrating field observations and surface weathering reflections of these fractures as observed in the lidar, we can demonstrate a widespread impact of early fracturing more akin to analogous early-lithified margins such as the Devonian of the Canning Basin of Australia. / text

Pre-existing structural elements can have substantial effects on fracture and fault development in younger strata, especially in areas that undergo significant changes in tectonic setting due to reactivation along older structures. This may affect reservoir permeability, yet remain difficult to detect in subsurface data. The focus of this study centers on two styles of pre-existing structures—Paleozoic thrust belts and Late Triassic rift faults in the Devils River Uplift and Maverick Basin, respectively—which affect the development of faults and fractures in Cretaceous strata. Fault and fracture data were characterized in both the outcrop and within a 3D seismic volume. Furthermore, the role of mechanical stratigraphy on fault and fracture style in both localities was examined. The Pecos River Canyon overlies the Paleozoic Ouachita fold-thrust belt with associated EW and SE-NW trending structures. At the surface, faults are expressed in two predominant orientations (N38E and N70E), which may be predictable angles if the pre-existing structures are reactivated by left lateral oblique slip. Detailed investigation of the fracture development related to these faults was conducted in a dry side canyon along the Pecos River. Mechanical layers were identified and mapped in outcrop to highlight fracture intensity variations between the different layers. The porosity and/or the degree of dolomitization are identified as controls on fracture development, with the lowest strength layer and least fractured being highly dolomitized with the largest porosity of any observed layer in outcrop. Southeast of Lewis Canyon, a 3D seismic of the Maverick Basin reveals linear discontinuities, interpreted as low-offset faults, within the Cretaceous Glen Rose through Austin Chalk that appear similar to those observed in outcrop along the Lower Pecos River. These faults are shown to have an increase in intensity within strata above older Late Triassic-age rift faults. It is proposed that the small faults form during reactivation of the rift faults and exhibit differential degrees of intensity and vertical terminations against six identified mechanical boundaries observed within the 3D seismic volume. / text

Small-scale morphology of gas hydrate is important for understanding the formation of gas hydrate deposits, for estimating the concentrations of gas hydrate from geophysical data, and for predicting their response to climate change or commercial production. The recent use of borehole pressure coring tools has allowed marine gas-hydrate-bearing sediments to be recovered with centimeter to sub-millimeter gas hydrate structures preserved in their in situ condition. Once these sediment samples are recovered at in situ temperature and pressure, nondestructive analyses, including gamma density, P-wave velocity, and X-ray imaging, are used to examine the character of the gas hydrate relative to the structure of the surrounding sediment. Gas hydrate morphology from pressure core data is summarized from the recent national gas hydrate expeditions of India, China, and Korea, as well as from Ocean Drilling Program Leg 204, Integrated Ocean Drilling Program Expedition 311, and the Gulf of Mexico Chevron-Texaco Joint Industry Project. The most striking result is the variability of gas hydrate morphology in clay, ranging from complex vein structures to an invisible pore-filling matrix. Both of these morphologies have been observed in clay sediments at gas hydrate saturations equivalent to 30-40% of pore volume. A clear knowledge of detailed gas hydrate morphology will provide important data to help determine the mechanisms of gas hydrate deposit formation and also provide crucial data for modeling the kinetics of deposit dissociation, from both natural and artificial causes. The morphology also has large effects on sedimentary physical properties, from seismic velocities on a large scale to borehole electrical resistivities on a smaller scale, and gas hydrate morphology will therefore impact estimation of gas hydrate saturation from geophysical data. The detailed morphology of gas hydrate is an essential component for a full understanding of the past, present, and future of any gas hydrate environment.

Fractures in the distal of the forearm are the most popular fractures of the muscular skeletal system. The aim of this study was to evaluate the effectiveness of joints mobilization method after fractures in the distal of the forearm. The goals of the study: To evaluate the effectiveness of different physical therapeutics methods in reconstruction of hand joints’ amplitudes as well as local hand brawn and function. To estimate the influence of different physical therapeutics methods on the change of hand pain while reconstructing hand’s functions. Organization and methods of the study. The examination was performed with patients grouped into two groups according to casual selection: 1. experimental group – patients underwent active and passive exercises and the joints mobilization method; 2. control group – patients underwent active and passive physical therapeutics exercises. Each group consisted of 30 patients whose mean age accordingly is 52,6±2,3 and 51,6±3,4 years. The study was performed at Kaunas Red Cross Hospital. A closed reduction was performed on all the patients after fracture in the distal of the forearm. Immobilization period lasted for 5 – 6 weeks. The physical therapeutics was started 3 – 5 days after removing the immobilization. Active exercises, passive movements of wrist and fingers joints and mobilization of the joints were applied to the patients of the experimental group. Passive movements as well as active exercises of wrist and fingers joints... [to full text]

Osteoporosis, a classical age-related disease and known to be more common in women than in men, has been reported increasingly often in men during the past few years. Although men at all ages after puberty have larger bones than women, resulting in greater bending strength, mortality after a hip fracture, one of the major complications of osteoporosis, is more common in men than in women. Sex hormone deficiency is associated with unrestrained osteoclast activity and bone loss. Even though estrogen deficiency is more pronounced in women, it appears to be a major factor in the pathogenesis of osteoporosis in both genders. In contrast to osteoporosis in postmenopausal women, the treatment of osteoporosis in men has been scarcely reported. Nevertheless, some drugs commonly used for the treatment of osteoporosis in women also appear to be effective in men. The aim of this study is to review primary osteoporosis in the elderly with particular emphasis on gender-related aspects. / Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.