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Background The arthroscopic method offers a less invasive technique of Bankart repair for traumatic anterior shoulder instability. The aim of the study is to determine the mid−/long-term functional outcome, failure rates and predictors of failure after primary arthroscopic Bankart repair for traumatic anterior shoulder instability. Methods A total of 100 patients were primarily operated using arthroscopic Bankart repair after traumatic anterior shoulder instability. Medical records were retrospectively reviewed, and patients were assessed using postal questionnaire after a mean follow-up of 8.3 years [3–14]. Clinical assessment was performed using Constant score, Rowe score, and American Shoulder and Elbow Surgeons score. Results The overall recurrence rate was 22%. The Kaplan-Meier failure-free survival estimates. were 80% at 5 years and 70% at 10 years. Nearly half (54.5%) of recurrences occurred at 2 years postoperative. Compared with normal shoulder, there were statistical differences in all 3 scores. Failure rate was significantly affected by age at the time of surgery with 86% of recurrence cases observed in patients aged 30 years or younger. Nevertheless, Younger age at the time of surgery ( P  = 0.007) as well age at the time of initial instability ( P  = 0.03) was found to correlate negatively with early recurrence within 2 years of surgery. Among those with recurrent instability, recurrence rate was found to be higher if there had been more than 5 instability episodes preoperatively ( P  = 0.01). Return to the preinjury sport and occupational level was possible in 41 and 78%, respectively. Conclusion Failure-free survival rates dropped dramatically over time. Alternative reconstruction techniques should be considered in those aged ≤30 years due to the high recurrence rate.

To faithfully transmit genetic information, cells must replicate their entire genome before division. This is thought to be ensured by the temporal separation of replication and chromosome segregation. Here we show that in 20-40% of unperturbed yeast cells, DNA synthesis continues during anaphase, late in mitosis. High cyclin-Cdk activity inhibits DNA synthesis in metaphase, and the decrease in cyclin-Cdk activity during mitotic exit allows DNA synthesis to finish at subtelomeric and some difficult-to-replicate regions. DNA synthesis during late mitosis correlates with elevated mutation rates at subtelomeric regions, including copy number variation. Thus, yeast cells temporally overlap DNA synthesis and chromosome segregation during normal growth, possibly allowing cells to maximize population-level growth rate while simultaneously exploring greater genetic space.

Part I of this series of publications addressed the background and fundamentals of the lifetime assessment of prototype Francis turbines. Part II concentrated on the developed methods of numerical calculation and assessment procedures. The present contribution (Part III) deals with the instrumentation and the metrological range of the assessment procedure. The most important sensors, measurement tools, and data acquisition units are presented (background). The instrumentation of the prototype Francis turbine is used, on the one hand, for machine unit monitoring and plant operating and, on the other hand, for generating measurement data to validate and adjust/correct the numerical simulations. Measurement data form the basis for further evaluations at various levels. A wide variety of measured variables are required to carry out the remaining lifetime of a component using fatigue analysis. Those variables include pressure and acceleration signals, vibration monitoring, and strain gauge applications for mechanical stress analysis. The available measurement signals are divided into groups based on the developed method. Thus, already-available data from the control room are compared with machine monitoring and temporarily measured data. The correlation of all available data is essential today to determine an exact idea of the occurring flow phenomena and their effects on the mechanical stresses on the component. This interaction of the different data sources and, subsequently, the use of selected quantities for the numerical calculation are part of the newly developed concept for fatigue strength analysis of mechanical components of a turbine unit (methods). The results of this journal article are divided into the discussion of the necessary instrumentation and mounting of the sensors and into the evaluation, presentation, and interpretation of the measurement data. In addition, a fatigue strength assessment is made at the position of the strain gauges. These results serve as a basis for validating the numerical stress calculation. It is worth mentioning that the validation of the numerical results and the discussion of the deviations and error consideration is carried out in Part IV of this publication series (results). This journal article of the series on condition assessment of prototype Francis turbines ends with a discussion of the results and conclusions for further data processing (conclusion).

Background The preservation or restoration of hip geometry following total hip arthroplasty (THA) is of importance, considering that alterations in the centrum-collum-diaphysis (CCD)-angle, femoral offset (FO), acetabular offset (AO) and total offset (TO) change hip biomechanics. Therefore, the most suitable implant should be used. The aim of this study was to compare the ability of two short-stem-systems and one straight-stem-system to reconstruct hip geometry. Methods Two-hundred-fifty-one patients (mean age: 62.0 ± 10.0 years; 51.8% males) undergoing THA with three different stem types were retrospectively included, after excluding 11 patients with missing radiological follow-up. Pre- and postoperative radiographic images (group I, ANA.NOVA Alpha Schaft Proxy®, ImplanTec , 12 options: n  = 99; group II, Optimys® Mathys , 24 options: n  = 62; group III: Corail®-System , DePuy-Synthes , 76 options: n  = 90) were analyzed. Differences in pre- and postoperative hip geometry (i.e. CCD, FO, AO, TO) were compared between groups with one-way-analysis-of-variance (ANOVA), and post-hoc t-tests. Results The CCD-angle increased by a mean of 8.4° ± 7.2° from pre-to postoperative, with no significant difference between groups ( p  = 0.097). Significantly larger increases in FO were observed for groups II (4.1 mm ± 7.8 mm) and III (4.9 ± 7.2 mm), in comparison to group I (1.6 ± 6.9 mm; p  = 0.006). AO decreased by a mean of 2.2 ± 4.5 mm, with the largest decrease observed in group III (-3.3 ± 5.3 mm), and the smallest for group I (-1.4 ± 3.6 mm; p  = 0.011). There was no significant difference in change of TO between groups ( p  = 0.177). Conclusions Reconstruction of hip geometry using a single-version novel short-stem-system is achievable with comparable results to stem-systems offering multiple options.

Background Thigh pain and cortical hypertrophies (CH) have been reported in the short term for specific short hip stem designs. The purpose of the study was to investigate 1) the differences in clinical outcome, thigh pain and stem survival for patients with and without CHs and 2) to identify patient and surgery-related factors being associated with the development of CHs. Methods A consecutive series of 233 patients with 246 hips was included in the present retrospective diagnostic cohort study, who had received a total hip arthroplasty (THA) between December 2007 and 2009 with a cementless, curved, short hip stem (Fitmore, Zimmer, Warsaw, IN, USA). Clinical and radiographic follow-up, including the radiographic parameters for hip geometry reconstruction, were prospectively assessed 1, 3, and 6 to 10 years after surgery. Results Cortical hypertrophies were observed in 56% of the hips after a mean of 7.7 years, compared to 53% after 3.3 years being mostly located in Gruen zone 3 and 5. There was no significant difference for the Harris Hip Score and UCLA score for patients with and without CHs. Only one patient with a mild CH in Gruen zone 5 and extensive heterotopic ossifications around the neck of the stem reported thigh pain. The Kaplan Meier survival rate after 8.6 years was 99.6% (95%-CI; 97.1–99.9%) for stem revision due to aseptic loosening and no association with CHs could be detected. Postoperative increase in hip offset was the only risk factor being associated with the development of CHs in the regression model (ΔHO; OR 1.1 (1.0–1.2); p  = 0.001). Conclusions The percentage of cortical hypertrophies remained almost constant in the mid-term compared to the short-term with the present cementless short hip stem design. The high percentage of cortical hypertrophies seems not be a cause for concern with this specific implant in the mid-term. Level of evidence Diagnostic Level IV

The modification of surface geometries to reduce friction is an omnipresent topic of research. In nature, different low-friction surfaces, such as fish skins, exist. To transfer this knowledge to technical applications, for example, to journal or plain bearings, many numerical and experimental studies of textured surfaces have been performed. In this work, the influence of the geometric parameters (texture length l, width b, angle α and start position xstart) of a wedge-shaped texture on three different convergent oil film gaps was analyzed in full-film lubrication and compared with untextured oil film gaps. With the aid of a CFD (computational fluid dynamics) model, a comprehensive variation study was conducted, and the best-performing wedge-shaped texture was determined. The results show that an open texture at the inlet provides the largest improvement. Furthermore, it can be observed that the optimal relative texture width and absolute inlet height for the three investigated oil film gaps are similar. In contrast to the volume flow of the untextured geometry, the volume flow of the textured one is significantly higher, especially that perpendicular to the movement direction.

Background The aim of this study is to compare the functional midterm outcome of stemless shoulder prostheses with standard anatomical stemmed shoulder prostheses and to show that the STEMLESS results are comparable to the STEMMED with respect to active maximum range of shoulder motion (ROM) and Constant score (CS). Methods Seventeen patients underwent total shoulder arthroplasty (TSA) in 25 shoulder joints. Stemless TSA was performed in 12 shoulder joints (group STEMLESS), third-generation stemmed TSA in 13 shoulder joints (group STEMMED). Functional results were documented using the CS. 3D-motion-analysis using the Heidelberg upper extremity model (HUX) was conducted to measure active maximum (ROM). Results The group STEMLESS achieved a CS of 67.9 (SD 12.0) points and the group STEMMED of 70.2 (SD 5.8 points) without significant difference between the groups ( p  = 0.925). The maximum ROM of the group STEMLESS, ascertained by 3-D-motion-analysis, was in forward flexion 125.5° (SD 17.2°), in extension 49.4° (SD 13.8°), in abduction 126.2° (SD 28.5°) and in external rotation 40.3° (SD 13.9°). The maximum ROM of the group STEMMED, also ascertained by 3-D-motion analysis, was in forward flexion 135.0° (SD 16.8°), in extension 47.2° (SD 11.5°), in abduction 136.3° (SD 24.2°) and in external rotation 40.1° (SD 12.2°). The maximum ROM of the STEMLESS group was lower in forward flexion and abduction, higher in extension and almost identical in external rotation. But there was no significant difference (forward flexion p  = 0.174, extension p  = 0.470, abduction p  = 0.345, external rotation p  = 0.978). Conclusion Both types of shoulder prostheses achieve a similar and good active ROM and similar results in CS. Trial registration DRKS00013166 , retrospectively registered, 11.10.2017

Surface topography has a significant influence on the friction behaviour in lubricated contacts. During running-in, the surface topography is continuously changed. The surface structure influences the contact stiffness (asperity contact pressure) as well as the microhydrodynamics (flow factors). In this study, different models for wear simulation of real rough surfaces were created in Matlab© (MathWorks, Natick, MA) and Abaqus© (ABAQUS Inc., Palo Alto, CA, USA) using the Usersubroutine Umeshmotion. The arithmetic mean height Sa(wh), the maximum height Sz(wh), as well as the asperity contact pressure pasp(h,wh) as a function of the wear height (wh) are used to characterise the surface for the respective wear state. The surface characteristics obtained from the simulations are validated with parameters from experiments. The aim of this study was to create a simulation methodology for mapping surface development during the running-in process. The results show, that the qualitative course of the surface parameters can be reproduced with the applied simulation methodology. Compared to the experiments, the rough surfaces are flattened faster. By adapting the simulation results in postprocessing, good agreements with the experiments can be achieved.

Anaphase chromatin bridges can lead to chromosome breakage if not properly resolved before completion of cytokinesis. The NoCut checkpoint, which depends on Aurora B at the spindle midzone, delays abscission in response to chromosome segregation defects in yeast and animal cells. How chromatin bridges are detected, and whether abscission inhibition prevents their damage, remain key unresolved questions. We find that bridges induced by DNA replication stress and by condensation or decatenation defects, but not dicentric chromosomes, delay abscission in a NoCut-dependent manner. Decatenation and condensation defects lead to spindle stabilization during cytokinesis, allowing bridge detection by Aurora B. NoCut does not prevent DNA damage following condensin or topoisomerase II inactivation; however, it protects anaphase bridges and promotes cellular viability after replication stress. Therefore, the molecular origin of chromatin bridges is critical for activation of NoCut, which plays a key role in the maintenance of genome stability after replicative stress. Mendoza and colleagues provide insights into the specificity of the NoCut checkpoint, showing that although different types of chromosomal defects delay cytokinetic abscission, only after replication stress does this prevent DNA damage.

Part I of the publication series addressed the fundamentals of lifetime assessment of prototype Francis turbines. This paper (Part II) focuses on the numerical part of the procedure. The essential steps and requirements shall be presented (background). The starting points for the numerical considerations are the pressure fields of the transient CFD simulations, which are exported per time step and applied to the existing structure via a fluid–structure interaction. That enables a transient mechanical stress calculation to be conducted, resulting in the fatigue analysis of the component to estimate the remaining lifetime. The individual model requirements should be represented accordingly and applied to the prototype facility (method). The results obtained from this application should be discussed and evaluated. It has to be mentioned that the validation of the numerical results will be performed at Part IV of this publication series (results). The present paper will end up discussing the results and conclusions about further data processing (Conclusion).