High-Precision Low-Cost Gimballing Platform for Long-Range Railway Obstacle Detection.

Increasing demand for rail transportation results in denser and more high-speed usage of the existing railway network, making new and more advanced vehicle safety systems necessary. Furthermore, high traveling speeds and the large weights of trains lead to long braking distances-all of which necessitates a Long-Range Obstacle Detection (LROD) system, capable of detecting humans and other objects more than 1000 m in advance. According to current research, only a few sensor modalities are capable of reaching this far and recording sufficiently accurate data to distinguish individual objects. The limitation of these sensors, such as a 1D-Light Detection and Ranging (LiDAR), is however a very narrow Field of View (FoV), making it necessary to use high-precision means of orienting to target them at possible areas of interest. To close this research gap, this paper presents a high-precision pointing mechanism, for the use in a future novel railway obstacle detection system, capable of targeting a 1D-LiDAR at humans or objects at the required distance. This approach addresses the challenges of a low target price, restricted access to high-precision machinery and equipment as well as unique requirements of our target application. By combining established elements from 3D printers and Computer Numerical Control (CNC) machines with a double-hinged lever system, simple and low-cost components are capable of precisely orienting an arbitrary sensor platform. The system's actual pointing accuracy has been evaluated using a controlled, in-door, long-range experiment. The device was able to demonstrate a precision of 6.179 mdeg, which is at the limit of the measurable precision of the designed experiment.

Singleton-Merten syndrome: A rare cause of femoral head necrosis.

Singleton-Merten syndrome (SMS) is a type I interferonopathy. In this report, we disclose the first-to the best of our knowledge-direct association of SMS with femoral head necrosis (FHN). The following case report presents the condition of a 38-year-old male suffering from SMS with FHN, characterized by acute symptoms and rapid disease progression. As per the recommendations of the Association Research Circulation Osseous (ARCO) and the S3-guidelines, we successfully treated the FHN with core decompression. Our histological results correlate with the changes described in medical literature in patients with SMS and MDA5-knockout in vivo experiments such as osteopenia, widened medullary cavity, and thin cortical bone. Moreover, the conducted immunohistochemistry shows strong CD56 positivity of the osteoblasts and osteocytes, as well as significant CD68 and CD163 positivity of the middle-sized osteoclasts. Collectively, these findings suggest an underlying syndrome in the FHN. A six-month post-operative follow-up revealed complete recovery with the absence of the initial symptoms and ability to resume normal daily activities. Taken together, our findings suggest that SMS is an additional cause of FHN in young adults. Early detection and adequate treatment using well-established joint-preserving techniques demonstrate a favorable improvement of the patient's clinical condition.

[Risk factors affecting mortality in patients with hip fractures at a regional trauma center]. / Einflussfaktoren auf die Mortalität bei Patienten mit hüftgelenknahen Frakturen an einem regionalen Traumazentrum.

BACKGROUND: Primary care hospitals and regional trauma centers play an essential role in the treatment of hip fractures. OBJECTIVE: This study investigated the relationship between patient-related parameters and in-hospital mortality as well as complications of hip fractures at a regional trauma center. METHODS: In a retrospective study, data were collected from all patients > 60 years admitted over 2 years to a regional trauma center with a hip fracture. Patient-related parameters included age, sex, fracture location, method of surgical treatment, time of surgery, duration of surgery, length of inpatient stay, blood transfusion, complications, comorbidities, use of anticoagulant medication and need for postoperative intensive care treatment. The relationship between these parameters and hospital mortality as well as complications was investigated. RESULTS: Data were collected from 360 patients undergoing 335 surgeries (f:m 225:110) with a mean age of 83 ± 8 years. The total in-hospital mortality rate was 7.76% (n = 26). Factors increasing in-hospital mortality included: age > 85 years (odds ratio [OR] 5.126; 95% confidence interval [CI] 0.665-39.498; p = 0.1167); male sex (OR 1.85 95%-CI [0.82-4.14]; p = 0.0555); time of surgery > 24 h (OR 1.896 95%-CI [0.661-5.441]; p = 0.2341); ≥ 3 comorbidities (OR 10.61 95%-CI [3.681-27.501]; p < 0.0001); intake of anticoagulants (OR 6.19 95%-CI [2.69-14.24]; p < 0.0001) and postoperative intensive care (OR 5.9 95%-CI [2.56-13.76]; p < 0.0001). CONCLUSION: In the present study a statistically significant influence of the number of comorbidities or Charlson comorbidity index, the intake of anticoagulant drugs and need for postoperative intensive care treatment on the in-hospital mortality of patients with proximal femoral fractures in a regional trauma center was found.

Vitamin D level and low-energy fracture risk in children and adolescents: a population-based case-control study of 45 cases.

The objective is to document the rate of vitamin D deficiency and insufficiency among children with low-energy fractures and compare it to fracture-free control group. We included all children under 15 years presenting to the emergency department with low-energy fractures; controls were children without history of fractures from the outpatient department. Conventional X-ray and laboratory blood tests were performed. Vitamin D deficiency was defined as serum level ≤20 ng/ml, and the mean values were compared through two-sample t-tests. The influence of vitamin D on the fractures was defined using Chi-square test, significance with P-value < 0.05. The relationships between variables and odds of fracture occurrence were examined using logistic regression models. The final sample included 37 cases (30 males, 7 females, 7.4 ± 3.7 years) and 70 control individuals (42 males, 28 females, 7.8 ± 4.6 years) without significant differences regarding age, sex, and month of inclusion. Children with fractures had lower levels of vitamin D (21.87 ± 8.40 ng/ml vs. 25.89 ± 7.62 ng/ml) (P = 0.01). Vitamin D played a protective role against low-energy fractures (OR, 1.08; 95% CI, 1.01-1.14; P = 0.02), boys showed three times greater fracture risk than girls (OR, 3.00; 95% CI, 1.12-8.07; P = 0.03). Finally, vitamin D deficiency correlated with almost five times increased risk of pediatric low-energy fractures (OR, 4.63; 95% CI, 1.92-11.18; P = 0.001). This is the first MENA study establishing a relation between vitamin D deficiency and low-energy fractures among children and adolescents. The findings show the protective role of vitamin D on the pediatric bone and may help physicians preventing morbidity on children and costs on their families and the socioeconomic health system.

Cemented versus Cementless Stem Fixation in Revision Total Knee Arthroplasty: A Systematic Review and Meta-Analysis.

The number of revision knee arthroplasties (rTKA) is growing significantly as is the use of intramedullary stems for optimized stability. The choice of the most appropriate stem fixation method is still controversial. The purpose of this meta-analysis is to compare cemented versus cementless stem fixation in rTKA. Publications with patients undergoing rTKA with a follow-up > 24 months were systemically reviewed. Extracted parameters included total revision and failure rates for any reason, incidence of aseptic loosening, periprosthetic infection, and radiolucent lines, as well as the clinical outcome. A statistical regression analysis was then performed on all extracted clinical and radiological outcome data. A total of 35 publications met the inclusion criteria and were included and analyzed. Overall, 14/35 publications compared cementless versus cemented stem fixation, whereas 21/35 publications investigated only one stem fixation method. There were no significant differences in revision (p = 0.2613) or failure rates (p = 0.3559) and no differences in the incidence of aseptic loosening (p = 0.3999) or periprosthetic infection (p = 0.1010). The incidence of radiolucent lines was significantly higher in patients with cemented stems (26.2% versus 18.6%, p < 0.0001). However, no differences in clinical outcomes were observed. No superiority of a specific stem fixation method in rTKA was found. Rates of revision or failure for any reason as well as incidence of aseptic loosening and periprosthetic infection in cemented versus cementless stem fixation showed no significant difference. A higher incidence of radiolucent lines was observed in cemented stem fixation; however, no effect was observed on the clinical outcome.

Periprosthetic Infections of the Shoulder Joint: Characteristics and 5-Year Outcome of a Single-Center Series of 19 Cases.

Periprosthetic shoulder infection (PSI) remains a devastating complication after total shoulder arthroplasty (TSA). Furthermore, there is a paucity in the literature regarding its diagnostic and therapeutic management, especially the absence of therapy concepts devised exclusively for PSI. The aim of the presenting study is to examine the characteristics and outcome of patients with PSI who were treated according to well-established algorithms developed originally for periprosthetic joint infection (PJI) of the hip and knee and determine if these algorithms can be applied to PSI. This single-center case series included all patients with a PSI presenting between 2010 and 2020. Recorded parameters included age, sex, affected side, BMI, ASA score, Charlson comorbidity index, preoperative anticoagulation, indication for TSA (fracture, osteoarthritis or cuff-arthropathy), and type of infection (acute or chronic PSI). The outcome was divided into treatment failure or infect resolution. Staphylococcus epidermidis and aureus were the commonest infecting pathogens. Acute PSI was mainly treated with debridement, irrigation, and retention of the prosthesis (DAIR) and chronic cases with two/multiple-stage exchange. The treatment failure rate was 10.5%. C-reactive protein was preoperatively elevated in 68.4% of cases. The mean number of operative revisions was 3.6 ± 2.6, and the mean total duration of antibiotic treatment was 72.4 ± 41.4 days. The most administered antibiotic was a combination of clindamycin and fluoroquinolone. In summary, the data of the current study suggest that therapeutical algorithms and recommendations developed for the treatment of PJI of the hip and knee are also applicable to PSI.

Superinfection with Difficult-to-Treat Pathogens Significantly Reduces the Outcome of Periprosthetic Joint Infections.

Periprosthetic joint infection (PJI) is a serious complication after total joint arthroplasty. In the course of a PJI, superinfections with pathogens that do not match the primary infecting micro-organism may occur. To our knowledge, there are no published data on the outcome of such infections in the literature. The aim of this study was to assess the outcome of PJI with superinfections with a difficult-to-treat (DTT) pathogen. Data of 169 consecutive patients with PJI were retrospectively analyzed in this single-center study. Cases were categorized into: Group 1 including non-DTT-PJI without superinfection, Group 2 DTT-PJI without superinfection, Group 3 non-DTT-PJI with DTT superinfection, and Group 4 non-DTT-PJI with non-DTT superinfection. Group 3 comprised 24 patients and showed, after a mean follow-up of 13.5 ± 10.8 months, the worst outcome with infection resolution in 17.4% of cases (p = 0.0001), PJI-related mortality of 8.7% (p = 0.0001), mean revision rate of 6 ± 3.6 (p < 0.0001), and duration of antibiotic treatment of 71.2 ± 45.2 days (p = 0.0023). PJI caused initially by a non-DTT pathogen with a superinfection with a DTT pathogen is significantly associated with the worst outcome in comparison to non-DTT-PJI, PJI caused initially by a DTT pathogen, and to non-DTT-PJI with a non-DTT superinfection.

Delayed Rifampin Administration in the Antibiotic Treatment of Periprosthetic Joint Infections Significantly Reduces the Emergence of Rifampin Resistance.

Rifampin is one of the most important biofilm-active antibiotics in the treatment of periprosthetic joint infection (PJI), and antibiotic regimens not involving rifampin were shown to have higher failure rates. Therefore, an emerging rifampin resistance can have a devastating effect on the outcome of PJI. The aim of this study was to compare the incidence of rifampin resistance between two groups of patients with a PJI treated with antibiotic regimens involving either immediate or delayed additional rifampin administration and to evaluate the effect of this resistance on the outcome. In this retrospective analysis of routinely collected data, all patients who presented with an acute/chronic PJI between 2018 and 2020 were recorded in the context of a single-center comparative cohort study. Two groups were formed: Group 1 included 25 patients with a PJI presenting in 2018-2019. These patients received additional rifampin only after pathogen detection in the intraoperative specimens. Group 2 included 37 patients presenting in 2019-2020. These patients were treated directly postoperatively with an empiric antibiotic therapy including rifampin. In all, 62 patients (32 females) with a mean age of 68 years and 322 operations were included. We found a rifampin-resistant organism in 16% of cases. Rifampin resistance increased significantly from 12% in Group 1 to 19% in Group 2 (p < 0.05). The treatment failure rate was 16% in Group 1 and 16.2% in Group 2 (p = 0.83). The most commonly isolated rifampin-resistant pathogen was Staphylococcus epidermidis (86%) (p < 0.05). The present study shows a significant association between the immediate start of rifampin after surgical revision in the treatment of PJI and the emergence of rifampin resistance, however with no significant effect on outcome.