Conversion Total Hip Arthroplasty in Patients With Osteopetrosis: Insights From Two Unique Cases.

CASE: Two patients with osteopetrosis underwent conversion total hip arthroplasty (THA) after failure of internal fixation due to hip fractures. We experienced challenges, including difficulty of hardware removal, remaining of previous broken screws in the canal, difficulty in finding the femoral canal, and an intraoperative acetabulum fracture. Despite complications, both patients achieved satisfactory functional outcome after surgery at the latest follow-up. CONCLUSION: Our cases showed that previous hip fracture and failed internal fixation make conversion THA more complex and unpredictable in patients with osteopetrosis. This in turn underscores the critical need for advanced preoperative planning, intraoperative flexibility, and meticulous postoperative care.

A mechanistic simulation of induced DNA damage in a bacterial cell by X- and gamma rays: a parameter study.

Mechanistic Monte Carlo simulations calculating DNA damage caused by ionizing radiation are highly dependent on the simulation parameters. In the present study, using the Geant4-DNA toolkit, the impact of different parameters on DNA damage induced in a bacterial cell by X- and gamma-ray irradiation was investigated. Three geometry configurations, including the simple (without DNA details), the random (a random multiplication of identical DNA segments), and the fractal (a regular replication of DNA segments using fractal Hilbert curves), were simulated. Also, three physics constructors implemented in Geant4-DNA, i.e., G4EmDNAPhysics_option2, G4EmDNAPhysics_option4, and G4EmDNAPhysics_option6, with two energy thresholds of 17.5 eV and 5-37.5 eV were compared for direct DNA damage calculations. Finally, a previously developed mathematical model of cell repair called MEDRAS (Mechanistic DNA Repair and Survival) was employed to compare the impact of physics constructors on the cell survival curve. The simple geometry leads to undesirable results compared to the random and fractal ones, highlighting the importance of simulating complex DNA structures in mechanistic simulation studies. Under the same conditions, the DNA damage calculated in the fractal geometry was more consistent with the experimental data. All physics constructors can be used alternatively with the fractal geometry, provided that an energy threshold of 17.5 eV is considered for recording direct DNA damage. All physics constructors represent a similar behavior in generating cell survival curves, although the slopes of the curves are different. Since the inverse of the slope of a bacterial cell survival curve (i.e., the D10-value) is highly sensitive to the simulation parameters, it is not logical to determine an optimal set of parameters for calculating the D10-value by Monte Carlo simulation.

Digital Screen Time and the Risk of Female Breast Cancer: A Retrospective Matched Case-Control Study.

Background: As the use of electronic devices such as mobile phones, tablets, and computers continues to rise globally, concerns have been raised about their potential impact on human health. Exposure to high energy visible (HEV) blue light, emitted from digital screens, particularly the so-called artificial light at night (ALAN), has been associated with adverse health effects, ranging from disruption of circadian rhythms to cancer. Breast cancer incidence rates are also increasing worldwide. Objective: This study aimed at finding a correlation between breast cancer and exposure to blue light from mobile phone. Material and Methods: In this retrospective matched case-control study, we aimed to investigate whether exposure to blue light from mobile phone screens is associated with an increased risk of female breast cancer. We interviewed 301 breast cancer patients (cases) and 294 controls using a standard questionnaire and performed multivariate analysis, chi-square, and Fisher's exact tests for data analysis. Results: Although heavy users in the case group of our study had a statistically significant higher mean 10-year cumulative exposure to digital screens compared to the control group (7089±14985 vs 4052±12515 hours, respectively, P=0.038), our study did not find a strong relationship between exposure to HEV and development of breast cancer. Conclusion: Our findings suggest that heavy exposure to HEV blue light emitted from mobile phone screens at night might constitute a risk factor for promoting the development of breast cancer, but further large-scale cohort studies are warranted.

Do blue light filter applications improve sleep outcomes? A study of smartphone users' sleep quality in an observational setting.

Exposure to blue light at bedtime, suppresses melatonin secretion, postponing the sleep onset and interrupting the sleep process. Some smartphone manufacturers have introduced night-mode functions, which have been claimed to aid in improving sleep quality. In this study, we evaluate the impact of blue light filter application on decreasing blue light emissions and improving sleep quality. Participants in this study recorded the pattern of using their mobile phones through a questionnaire. In order to evaluate sleep quality, we used a PSQI questionnaire. Blue light filters were used by 9.7% of respondents, 9.7% occasionally, and 80% never. The mean score of PSQI was more than 5 in 54.10% of the participants and less than 5 in 45.90%. ANOVA test was performed to assess the relationship between using blue light filter applications and sleep quality (p-value = 0.925). The findings of this study indicate a connection between the use of blue light filter apps and habitual sleep efficiency in the 31-40 age group. However, our results align only to some extent with prior research, as we did not observe sustained positive effects on all parameters of sleep quality from the long-term use of blue light filtering apps. Several studies have found that blue light exposure can suppress melatonin secretion, exacerbating sleep problems. Some studies have reported that physical blue light filters, such as lenses, can affect melatonin secretion and improve sleep quality. However, the impact of blue light filtering applications remains unclear and debatable.

Using smartphones before bedtime and being exposed to its blue light can make it harder to fall asleep and disrupt your sleep. Some smartphone makers have introduced a night mode feature claiming it can help improve your sleep. In this study, we wanted to find out if using these blue light filters on smartphones really makes a difference. We asked people how often they used blue light filters on their phones and also had them fill out a questionnaire about their sleep quality. Only about 10% of people said they used blue light filters regularly, another 10% used them occasionally, and the majority, around 80%, never used them. When we looked at the results, more than half of the participants had sleep scores higher than 5, indicating they might have sleep problems. Less than half had sleep scores lower than 5, suggesting better sleep quality. We used some statistical tests to see if using blue light filters had any link to sleep quality, and the results showed that there was only a connection between the use of blue light filter apps and habitual sleep efficiency in the 31­40 age group. Our findings matched what other studies have found before, that using blue light filters on smartphones may not significantly help improve sleep. So, while it might be a good idea to limit smartphone use before bed, using a blue light filter app may not be the magic solution for better sleep.

Prediction of acute methanol poisoning prognosis using machine learning techniques.

Methanol poisoning is a global public health concern, especially prevalent in developing nations. This study focuses on predicting the severity of methanol intoxication using machine learning techniques, aiming to improve early identification and prognosis assessment. The study, conducted at Loghman Hakim Hospital in Tehran, Iran. The data pertaining to individuals afflicted with methanol poisoning was retrieved retrospectively and divided into training and test groups at a ratio of 70:30. The selected features were then inputted into various machine learning methods. The models were implemented using the Scikit-learn library in the Python programming language. Ultimately, the efficacy of the developed models was assessed through ten-fold cross-validation techniques and specific evaluation criteria, with a confidence level of 95%. A total number of 897 patients were included and divided in three groups including without sequel (n = 573), with sequel (n = 234), and patients who died (n = 90). The two-step feature selection was yielded 43 features in first step and 23 features in second step. In best model (Gradient Boosting Classifier) test dataset metric by 32 features younger age, higher methanol ingestion, respiratory symptoms, lower GCS scores, type of visual symptom, duration of therapeutic intervention, ICU admission, and elevated CPK levels were among the most important features predicting the prognosis of methanol poisoning. The Gradient Boosting Classifier demonstrated the highest predictive capability, achieving AUC values of 0.947 and 0.943 in the test dataset with 43 and 23 features, respectively. This research introduces a machine learning-driven prognostic model for methanol poisoning, demonstrating superior predictive capabilities compared to traditional statistical methods. The identified features provide valuable insights for early intervention and personalized treatment strategies.

Concurrent Learning Approach for Estimation of Pelvic Tilt from Anterior-Posterior Radiograph.

Accurate and reliable estimation of the pelvic tilt is one of the essential pre-planning factors for total hip arthroplasty to prevent common post-operative complications such as implant impingement and dislocation. Inspired by the latest advances in deep learning-based systems, our focus in this paper has been to present an innovative and accurate method for estimating the functional pelvic tilt (PT) from a standing anterior-posterior (AP) radiography image. We introduce an encoder-decoder-style network based on a concurrent learning approach called VGG-UNET (VGG embedded in U-NET), where a deep fully convolutional network known as VGG is embedded at the encoder part of an image segmentation network, i.e., U-NET. In the bottleneck of the VGG-UNET, in addition to the decoder path, we use another path utilizing light-weight convolutional and fully connected layers to combine all extracted feature maps from the final convolution layer of VGG and thus regress PT. In the test phase, we exclude the decoder path and consider only a single target task i.e., PT estimation. The absolute errors obtained using VGG-UNET, VGG, and Mask R-CNN are 3.04 ± 2.49, 3.92 ± 2.92, and 4.97 ± 3.87, respectively. It is observed that the VGG-UNET leads to a more accurate prediction with a lower standard deviation (STD). Our experimental results demonstrate that the proposed multi-task network leads to a significantly improved performance compared to the best-reported results based on cascaded networks.

Simultaneous Tunnel Grafting and Anterior Cruciate Ligament Reconstructions Revision Using Double Suspensory Fixation: A Single-Stage Solution.

The anterior cruciate ligament (ACL) is often vulnerable to sports-related injuries, leading to numerous ACL reconstructions (ACLRs) annually in the United States. Although largely successful, these procedures face the risk of recurrent instability due to graft failure. ACLR failures are typically attributed to technical errors and patient-related factors, with improper positioning of the tibial and femoral tunnels as the most common technical mistake. Current 2-stage revision techniques involve primary bone grafting followed by secondary tendon graft placement, resulting in increased costs and extended rehabilitation times. This article proposes a single-stage revision strategy involving simultaneous tunnel grafting and ACLR revision. The method employs double suspensory fixation by adjustable loop buttons, thereby eliminating the dependence on metaphyseal bone stock for stable graft fixation. This new procedure may offer a more efficient and cost-effective approach, reducing the need for a second surgery and potentially allowing patients to return to normal activities more quickly.

Latent infections in conversion total hip arthroplasty following internal fixation of femoral neck fractures: a systematic review and meta-analysis of diagnostic methods.

BACKGROUND: Accurate diagnosis of latent infections prior to conversion total hip arthroplasty (THA) following internal fixation of femoral neck fractures is crucial for successful surgical outcomes. This systematic review aimed to provide a comprehensive evaluation of the current literature regarding the diagnosis of latent infections before conversion THA. METHODS: Systematic search of PubMed, EMBASE, and Cochrane (CENTRAL) databases was conducted, and the diagnostic accuracy of various markers and techniques was assessed. The quality of the included studies was evaluated using the QUADAS-2 instrument. RESULTS: Five studies comprising 661 patients were included in the review. Pooled analysis using C-reactive protein (CRP) as a diagnostic marker resulted in a sensitivity and specificity of 72% and 76%, respectively, while using erythrocyte sedimentation rate (ESR) yielded a sensitivity and specificity of 75% and 78%, respectively. Fibrinogen and platelet count showed lower sensitivity and specificity compared to CRP and ESR. The best combined markers were CRP and serum platelet count, with a sensitivity of 76% and specificity of 86% based on one study. CONCLUSION: Our review underscored the limitations and inconsistencies present in current diagnostic methods for latent infections in conversion surgery. Future research needs to focus on standardizing threshold values, exploring the potential of synovial fluid analysis, imaging techniques, and molecular methods, as well as developing tailored diagnostic algorithms. PROSPERO: CRD42023394757.

Evaluation of core decompression outcome in systemic lupus erythematosus with hip osteonecrosis: a retrospective cohort study.

BACKGROUND: Osteonecrosis is a major cause of morbidity for patients with systemic lupus erythematosus (SLE). Although core decompression is an approved and trusted technique to prevent further joint deterioration, this surgical method seems to be less beneficial for SLE patients. We aimed to evaluate the outcomes of core decompression in SLE patients with primary stages of femoral head osteonecrosis. METHODS: In this study, 23 patients (39 affected hip joints) with osteonecrosis of the femoral head with stage II of the disease, based on the Ficat-Arlet classification system, underwent core decompression. Also, patients demographic characteristics, clinical data, medication history, comorbidities, immunological findings, hip plain radiographs, history of total hip arthroplasty after core decompression, and patients satisfaction with joint function according to the Oxford hip score questionnaire were obtained. RESULTS: In the study, 53.8% of affected joints showed signs of radiographic deterioration in follow-up imaging. Sixty-one and a half percent (61.5%) of patients had unsatisfactory joint performance. A third (33.3%) of affected hip joints underwent total hip arthroplasty up to 5 years from core decompression. SLE patients with a history of receiving bisphosphonate were 83.2% less dissatisfied with their joint function than patients without a history of bisphosphonate use (P < 0.02). Of the 23 studied cases, the mean cumulative dose of prednisolone before and after core decompression surgery was 46.41 mg and 14.74 mg respectively. Besides, one case (2.6%) that had a high anti-phospholipid antibodies level during follow-up did not have any radiographic deterioration, and 9 cases (23.1%) had some degrees of radiographic deterioration. CONCLUSIONS: The patients group that used bis-phosphonate, had a higher level of satisfaction with joint function after core decompression. Patients with high-level anti-phospholipid antibodies are related to a poor prognosis after core decompression.

Indirect effects of interference of two emerging environmental contaminants on cell health: Radiofrequency radiation and gold nanoparticles.

BACKGROUND: The global need for wireless technologies is growing rapidly. So, we have been exposed to a new type of environmental pollution: radiofrequency radiation (RFR). Recent studies have shown that RFR can cause not only direct effects but also indirect or non-targeted effects such as the bystander effect (BE). In this study, we investigated the BE induced by RFR in the present of gold nanoparticles (GNP). Moreover, we studied the expression of cyclooxygenase-2 (COX-2). METHODS: Non-toxic dose of 15-nm GNP was used to treat the Chinese Hamster Ovary (CHO) cells. After 48 h of incubation, cells were exposed to 900 MHz GSM RFR for 24 h. Then we collected the cell culture medium of these cells (conditioned culture medium, CCM) and transferred it to new cells (bystander cells). Cell deaths, DNA breaks, oxidative stress and COX-2 expression were analyzed in all groups. RESULTS: The results showed that RFR increased metabolic death in cells treated with GNP. Inversely, the colony formation ability was reduced in bystander cells and RFR exposed cells either in the presence or absence of GNP. Also, the level of reactive oxygen species (ROS) in GNP treated cells showed a significant reduction compared to those of untreated cells. However, RFR-induced DNA breaks and the frequencies of micronuclei (MN) were not significantly affected by GNP. The expression of COX-2 mRNA increased in RFR GNP treated cells, but the difference was not significant. CONCLUSION: Our results for the first time indicated that RFR induce indirect effects in the presence of GNP. However, the molecular mediators of these effects differ from those in the absence of GNP. Also, to our knowledge, this is the first study to show that COX-2 is not involved in the bystander effect induced by 900 MHz RFR.

The impact of retaining the femoral stem in revision total hip arthroplasty: a systematic review, meta-analysis, and meta-regression.

INTRODUCTION: The management of well-fixed femoral stems in revision total hip arthroplasty (rTHA) remains a subject of debate, with concerns over potential complications arising from stem retention. This study aimed to investigate the re-revision rates due to aseptic loosening of the stem, overall re-revision rates, dislocation rates, and factors influencing these outcomes in rTHA with a retained well-fixed femoral stem. MATERIALS AND METHODS: A systematic search was conducted across several databases including PubMed, EMBASE, and CENTRAL to identify pertinent publications from their inception through 2023. We specifically focused on studies that reported outcomes of rTHA with retained well-fixed femoral stems. The study designs incorporated in our research encompassed both cohort studies and case series studies. Thirty-five studies involving isolated acetabular revision and retaining the stem were included, representing a total of 3497 patients. Data extraction was tailored to the study questions. Meta-analyses, meta-regression, and subgroup analyses were conducted to evaluate the outcomes and their relationship with various factors. Pooled results, meta-regression, and subgroup analyses were performed using random-effects models. To assess and reduce bias, we employed Egger's test and the trim and fill method. RESULTS: The meta-analysis included 3497 patients with a mean follow-up of 9.28 years. The 10-year risk of re-revision after retaining femoral stem using highly cross-linked polyethylene was 1.7% (95% CI 1.1%-2.3%; I2: 60%) for stem aseptic loosening and 8.8% (95% CI 6.2%-11.4%; I2: 78%) overall re-revision. Dislocation risk was 5.7% (95% CI 4.1-7.0%; I2: 61%). Ceramic heads showed lower stem failure risk than metal heads in long-term follow-ups (P < 0.001). The posterolateral approach in revision surgery resulted in better long-term outcomes compared to the direct lateral approach (P < 0.001). Follow-up duration, timeline of study, Harris Hip Score, type of stem fixation, femoral head material, BMI, age, stem age, and surgical approach were evaluated as influential factors on these outcomes. CONCLUSION: The re-revision rate due to aseptic loosening of the retained stem during rTHA was found to be significantly low, supporting the idea of retaining well-fixed stems during rTHA. The overall re-revision and dislocation rates also presented comparable or better outcomes to prior studies. A range of factors, including the use of highly cross-linked polyethylene and ceramic femoral heads, was found to influence these outcomes. LEVEL OF EVIDENCE: IV. PROSPERO REGISTRATION NUMBER: CRD42022351157.

Evaluation of core decompression outcome in systemic lupus erythematosus with hip osteonecrosis: a retrospective cohort study

Abstract Background Osteonecrosis is a major cause of morbidity for patients with systemic lupus erythematosus (SLE). Although core decompression is an approved and trusted technique to prevent further joint deterioration, this surgical method seems to be less beneficial for SLE patients. We aimed to evaluate the outcomes of core decompression in SLE patients with primary stages of femoral head osteonecrosis. Methods In this study, 23 patients (39 affected hip joints) with osteonecrosis of the femoral head with stage II of the disease, based on the Ficat-Arlet classification system, underwent core decompression. Also, patients demographic characteristics, clinical data, medication history, comorbidities, immunological findings, hip plain radiographs, history of total hip arthroplasty after core decompression, and patients satisfaction with joint function according to the Oxford hip score questionnaire were obtained. Results In the study, 53.8% of affected joints showed signs of radiographic deterioration in follow-up imaging. Sixty-one and a half percent (61.5%) of patients had unsatisfactory joint performance. A third (33.3%) of affected hip joints underwent total hip arthroplasty up to 5 years from core decompression. SLE patients with a history of receiving bisphosphonate were 83.2% less dissatisfied with their joint function than patients without a history of bisphospho-nate use (P < 0.02). Of the 23 studied cases, the mean cumulative dose of prednisolone before and after core decompression surgery was 46.41 mg and 14.74 mg respectively. Besides, one case (2.6%) that had a high anti-phospholipid antibodies level during follow-up did not have any radiographic deterioration, and 9 cases (23.1%) had some degrees of radiographic deterioration. Conclusions The patients group that used bis-phosphonate, had a higher level of satisfaction with joint function after core decompression. Patients with high-level anti-phospholipid antibodies are related to a poor prognosis after core decompression.

Single-stage bilateral conversion arthroplasty for hip fusion via direct anterior approach in a patient with severe ankylosing spondylitis and kyphoscoliosis: a case report.

BACKGROUND: Severe ankylosing spondylitis (AS) frequently involves hip joints and, occasionally, presents with concurrent spinal deformities, such as kyphoscoliosis, creating complex challenges for surgical management. CASE PRESENTATION: We present a 26-year-old Persian male with a history of AS and severe kyphoscoliosis, leading to bilateral hip fusion and immobility. Following spinal deformity correction, a one-stage bilateral conversion to total hip arthroplasty (THA) was conducted through the direct anterior approach. CONCLUSION: Primary correction of spinal deformities allows for extended surgical procedures under general anesthesia. Single stage bilateral hip conversion arthroplasty via the direct anterior approach enhances postoperative mobilization, reduce the risk of re-ankylosis, and improve the overall quality of life for AS patients with this unique presentation.

Mobile Cellular Data and Wi-Fi Use Are Not Associated with Adverse Health Effects.

Background: Smartphone users frequently connect to the Internet via mobile data or Wi-Fi. Over the past two decades, the worldwide percentage of people who connect to the Internet using their mobile phones has increased drastically. Objective: This study aimed to evaluate the potential link between mobile cellular data/ and Wi-Fi use and adverse health effects. Material and Methods: This cross-sectional study was conducted on 2,796 employees (52% female and 48% male) of Shiraz University of Medical Sciences (SUMS), Shiraz, Iran. The sociodemographic data (e.g., gender, age, nationality, and education level) were collected for all the participants. They were also requested to provide information about their smartphone use including the characteristics of the connection to the Internet using their smartphones (mobile data and Wi-Fi). In addition, the participants' history of diabetes, hypertension, cardiac ischemia, myocardial infarction, renal failure, fatty liver, hepatitis, chronic lung disease, thyroid disease, kidney stone, gall bladder stone, rheumatoid disease, epilepsy, and chronic headache was recorded through face-to-face interviews. Results: 94% of people participating in this study reported using mobile/Wi-Fi internet. The mean (±SD) Internet usage per day was 117.85±122.70 minutes including 76±98 minutes of mobile data and 42±81 minutes of Wi-Fi use. Conclusion: Our findings showed no link between mobile phone Internet usage and the risk of the above-mentioned health problems. As in 2021, the global average daily time spent on the Internet using mobile phones was 155 minutes, the participants' lower use time could explain the failure to show any detrimental effects. Considering the study limitations, further large-scale studies are warranted.

Genicular Artery Embolization for Knee Osteoarthritis: A Comprehensive Review.

¼ Genicular artery embolization (GAE) is a promising treatment option for patients with knee osteoarthritis who are unresponsive to nonsurgical treatments and not yet candidates for surgery.¼ Current evidence supports the effectiveness of GAE in reducing pain and synovitis, with few reported major adverse events.¼ The cost-effectiveness and long-term results of GAE compared with other treatment options require further investigation.¼ Limitations of existing studies include small sample sizes, single-center trials, and lack of comparison between embolic agents and other treatments.¼ Future research should focus on larger, multicenter trials with longer follow-up periods and head-to-head comparisons with alternative treatment modalities to establish the role of GAE in the management of knee osteoarthritis.

Family History of Alzheimer's Disease Increases the Risk of COVID-19 Positivity: A SUMS Employees Cohort-based Study.

Background: Substantial data indicate that genetic and environmental factors play a key role in determining the risk of Alzheimer's disease (AD). Moreover, it is known that having relatives with AD increases the risk of developing this disease. Objective: This study is aimed at investigating whether having a family history of AD, may increase the risk of COVID-19 in a cohort-based study. Material and Methods: Participants of this retrospective cohort study were previously enrolled in the SUMS Employees Cohort (SUMSEC). All participants including those whose SARS-CoV-2 infection was confirmed by positive PCR test and chest CT scan were requested to respond to interviewer-administered questionnaires. Moreover, AD was diagnosed via memory and thinking impairment, concentration problems, confusion with location, and problems in finishing daily tasks. Results: The total numbers of female and male participants with a family history of AD were 463 and 222 individuals, respectively. When all types of family history of AD were considered, a 51.3% increase was found in the relative frequency of the participants with both family history of AD and confirmed COVID-19 compared with those only with a family history of AD. Conclusion: Despite the limitations of our study, and from a broader perspective, our findings can further support the concept that AD risk haplotypes including APOE are linked to the same morbidities from cardiovascular disease and obesity that increase vulnerability to COVID-19. Given this consideration, millions of APOE ε4 carriers around the globe should be advised to take additional precautions to prevent life-threatening diseases such as COVID-19.

Medical education during the COVID-19 pandemic: lessons for the orthopedic departments.

BACKGROUND: After the Coronavirus pandemic, many educational routines were stopped for the safety of medical staff. To achieve educational goals, we have implemented new policies in our hospitals. In this study, we aimed to evaluate the effect of such strategies. METHOD: This survey-based study uses questionnaires to assess newly implemented educational strategies. We surveyed 107 medical staff of the orthopedic department of Tehran University of Medical Sciences, including faculty members, residents, and students. The survey contained three series of questionnaires for these groups. RESULTS: The maximum satisfaction for all three groups was observed in the platform and facilities for using e-classes, and the cost- and time-saving capabilities (Respectively, faculty members (FM): 81.8%, residents (R): 95.2%, students/interns (S/I): 87.0%; FM: 90.9%, R: 88.1%, S/I: 81.5%). The new policies have been shown to reduce the stress level of most trainees, increase the quality of knowledge-based education, increase the opportunity for reexamining educational content, expand discussion and research opportunities, and improve work conditions. There was a broad acceptance of the virtual journal clubs and morning reports. However, there were discrepancies between residents and faculty members on issues such as the evaluation of trainees, the new educational curriculum, and flexible shift schedules. Our strategies failed to improve skill-based education and patient treatment status. Most participants indicated that e-learning should be used with face-to-face training post-pandemic (FM: 81.8%, R: 83.3%, S/I: 75.9%). CONCLUSION: Our efforts to optimize the educational system during this crisis have generally improved trainees' work conditions and educational experience. Most participants believed that e-learning and virtual methods should be used alongside traditional training as a complementary component after the pandemic.

How Reactivation of SARS-CoV-2 in Astronauts with Dysregulated Immune Systems Can Negatively Affect the Odds of Success in Future Space Missions.

We have previously reported that during future space missions the risk of severe COVID-19 infection will be a cardinal issue that needs careful attention. Our studies show that even with the most reliable pre-mission screening and quarantine strategies, astronauts with a latent (hidden, inactive, or dormant) SARS-CoV-2 infection might be sent to space. Given this consideration, an asymptomatic individual with dormant SARS-CoV-2 infection may successfully pass all the pre-launch medical tests. Then during a space mission such as a journey to Mars or beyond, when the immune system of these astronauts starts to weaken, the dormant infection may progress to a severe infection that possibly affects the chance of the mission's success. The effects of microgravity and the elevated space radiation are two key factors that should be evaluated. Furthermore, the limited size of the spacecraft, the proximity of crew members during flight operations, spacecraft atmospheric composition, limited exercise capability, effects of viral response to space radiation, and uncertainty in the likelihood of the virus to mutate and evolve during a space mission merit additional study.

Slight pelvic obliquity is normal in a healthy population: a cross-sectional study.

PURPOSE: Pelvic obliquity (PO) has not been extensively investigated, and there is no gold standard for measurement. The PO is essential for surgeons in planning hip arthroplasty, which includes the restoration of leg length discrepancy (LLD). We aimed to establish a normative range of PO angles by measuring healthy individuals without musculoskeletal disorders. METHODS: Our study included 134 consecutive cases (70 females) referred to our institution between April 2020 and September 2021 for non-orthopedic problems. Patients were screened for normal gait and posture using the visual observation method (VOM) and the Modified Gait Abnormality Rating Scale (GARS-M). In standing standard radiographs, the PO angle was measured as the angle between the horizontal plane and the inter-teardrop line. RESULTS: Patients' mean age and Body Mass Index (BMI) were 39.7 ± 16.8 and 22.3 ± 3.1, respectively. PO angles did not follow a normal distribution, with a median (IQR) of 2.0° (0.9°-3.1°). According to the Wilcoxon one-sample test, the median PO angle differed significantly from zero (P < 0.001). The PO angle did not differ significantly between males and females (2° vs. 2°, P = 0.46), nor did it correlate significantly with age (P = 0.24). Considering the 95% percentile of PO angles was 5.6°, this range (0°-5.6°) was regarded as a normative value. CONCLUSION: Normative values for PO in the normal healthy population range from 0° to 5.6°, with a median value of 2.0°. The PO angle was independent of age and sex and differed significantly from 0°. Slight pelvic obliquity may be normal, and physicians should not always assume that it is caused by pain, scoliosis, or weakness of the abductors. LEVEL OF EVIDENCE: III.