Neck Strain Research Articles

Efficacy of craniosacral therapy in cervicogenic headache: a literature review

BackgroundNeck discomfort is a frequent problem that can impair quality of life and make it difficult to perform daily tasks. Pain from neck strain is not limited to the cervical spine; it can also radiate into the skull and result in a headache of cervical origin, known as cervicogenic headache. Craniosacral can cure a wide array of musculoskeletal and neurological conditions, including headaches, but there is little evidence in the literature of its efficacy, particularly regarding cervicogenic headaches.ObjectiveTo determine the effectiveness of craniosacral therapy (CST) for cervicogenic headache and improve our understanding of cervicogenic headache.MethodsA review of the literature was performed using the following electronic search bases: PubMed, Google Scholar, Scopus and The Cochrane library. To perform the search, these MeSH terms were used: “Cervicogenic headache” AND “Neck pain” AND “Craniosacral therapy” AND ‘Headache’ between the date 2020 to 2022.ResultsEleven articles were included in the literature review. Overall, the results of published articles indicate 97.5–100% of the patients thought the treatment program was satisfactory. No adverse effects were reported. It has been demonstrated that CST is particularly safe and effective in lowering the intensity of neck pain. It may also enhance the quality of life and functional impairment for up to three months following the intervention. In addition to the conventional medical therapy, CST may be a beneficial therapeutic option for persistent and recurrent neck discomfort.ConclusionThis review shows that CST is very effective for the treatment of cervicogenic headaches. CST evaluation is feasible in randomized controlled trials and may offer insightful results to enhance therapeutic decision-making.

Augmented reality visualization for ultrasound-guided interventions: a pilot randomized crossover trial to assess trainee performance and cognitive load

BackgroundAugmented reality (AR) technology involving head-mounted displays (HMD) represents a significant innovation in medical education, particularly for training in guided invasive procedures. Novice physicians often face challenges in simultaneously identifying anatomical landmarks and performing procedures when learning point-of-care ultrasound (POCUS). Our primary objective was to determine the effectiveness of AR in enhancing physician training for ultrasound-guided interventions using AR visual overlays. The secondary objective was to compare cognitive load between traditional ultrasound training settings and AR-assisted training settings.MethodsThis randomized crossover study, conducted from 2021 to 2022, compared performance and cognitive load of trainees attempting accurate central venous catheter (CVC) placement using an AR-HMD to display ultrasound images (AR-US), compared with standard ultrasound without visual overlay (S-US). We enrolled 47 trainees, including 22 final-year undergraduate medical students and 25 postgraduate physicians (years 1–4) from three hospitals in Taiwan. All participants had basic training in US-guided CVC placement but lacked AR-US experience. Performance and cognitive load were assessed using time measurements and NASA Task Load Index (NASA-TLX), covering the dimensions of Mental-, Physical- and Temporal Demand, and Performance, Effort and Frustration.ResultsWe found AR technology reduced the time required for critical steps in CVC placement, while minimizing users’ neck strain. Female and junior trainees using AR-US identified anatomy and localized veins faster than those using S-US. Using AR-US, female trainees significantly outperformed males in anatomical identification [mean difference (MD): -10.79 s (95% CI: -2.37 to -19.21)]. The NASA-TLX cognitive load assessment showed mental workload trending lower in all dimensions except performance while using AR-US, compared to S-US. Similarly, junior trainees’ effort- and frustration scores were lower [MD: -2.73 (95% CI: -5.04 to -0.41) and -2.41 (95% CI: -4.51 to -0.31), respectively], as were female trainees’ effort scores [MD: -3.07 (95% CI: -6.10 to -0.03)] when using AR-US, compared to S-US, whereby these differences were statistically significant.ConclusionsAR technology helped improve trainee performance and reduced cognitive load during ultrasound-guided CVC placement. These findings support the application of AR technology to enhance physician training in ultrasound-guided interventional procedures, suggesting that AR-HMDs could be a valuable tool in medical education.Trial registrationThe trial was registered with Clinicaltrials.gov on 20/09/2023 as a clinical trial, under the identifier NCT 06055400.

Impact of Smartphone Addiction on Neck Pain Among University Students

Background: Smartphone addiction is increasingly common among university students and has been linked to musculoskeletal issues, particularly neck pain, due to prolonged improper postures. This study aimed to investigate the impact of smartphone addiction on neck pain among university students.Objective: To evaluate the relationship between smartphone addiction and neck pain among university students.Methods: A cross-sectional study was conducted from January to June 2023 among 219 university students aged 18-35. Data were collected using the Smartphone Addiction Scale-Short Version (SAS-SV) and the Neck Disability Index (NDI). Convenience sampling was used, and exclusion criteria included neurological disorders, prior neck surgeries, or musculoskeletal diseases. Ethical approval was obtained following the Helsinki Declaration. Data were analyzed using IBM SPSS version 25. Chi-square tests and multivariate analysis were applied to assess associations, with a significance level of p < 0.05.Results: 34.2% of participants reported neck pain related to smartphone use. Among them, 43.8% experienced mild pain while reading on smartphones. The NDI showed that 15.1% had moderate pain, while 4.1% experienced fairly severe pain.Conclusion: Excessive smartphone use is significantly associated with neck pain among university students. Preventive strategies and ergonomic awareness are recommended to reduce neck strain.

Cervical epidural hematoma: a case series highlighting uncommon causes

BackgroundCervical epidural hematoma (CEH) is a rare but potentially devastating condition, characterized by the accumulation of blood within the epidural space of the cervical spine, leading to spinal cord compression (Perron AD, Huff JS. Spinal cord disorders. In: Marx JA, et al. editors. Rosen’s emergency medicine: concepts and clinical practice. 8th ed. Philadelphia: Saunders; 2013. pp. 1419–27.); (Raasck K, Habis AA, Aoude A, Simoes L, Barros F, Reindl R. Spontaneous spinal epidural hematoma management: a case series and literature review. Spinal Cord Ser Cases. 2017;3:16043. https://doi.org/10.1038/scsandc.2016.43.); (Ryo Yamamoto M, Ito H, Shimuzu K, Wakabayashi H, Oyama. Two cases of cervical epidural hematoma presenting with left-sided hemiplegia and requiring surgical drainage. Cureus. 2022;14(4):e23915. https://doi.org/10.7759/cureus.23915.). While trauma and iatrogenic causes are well-documented, cases attributed to neck strain and acupuncture are uncommon. (Raasck K, Habis AA, Aoude A, Simoes L, Barros F, Reindl R. Spontaneous spinal epidural hematoma management: a case series and literature review. Spinal Cord Ser Cases. 2017;3:16043. https://doi.org/10.1038/scsandc.2016.43.); (Shiraishi S, Goto I, Kuroiwa Y, Nishio S, Kinoshita K. Spinal cord injury as a complication of an acupuncture. Neurology. 1979;29(8):1188–90. https://doi.org/10.1212/wnl.29.8.1188.) Here, we present two cases of CEH secondary to these unusual aetiologies. Both cases highlight the importance of considering uncommon causes of CEH to ensure early recognition and prompt treatment.Case presentationsCase 1 is an 81-year-old lady who presented with left hemiparesis and paraesthesia following a fall with neck strain. Magnetic resonance imaging (MRI) of cervical spine revealed left C3-C7 epidural haematoma with severe cord compression. In Case 2, a 35-year-old gentleman experienced sudden onset numbness and weakness in all limbs just 10 minutes after receiving acupuncture. MRI showed an epidural hematoma at the C2-C4 levels. Both patients underwent immediate surgical decompression and had significant recovery.ConclusionAlthough CEH is a rare occurrence, it can potentially be a neurosurgical emergency. Physicians must remain cognizant of the diverse aetiologies associated with CEH and the necessity for early recognition and immediate treatment.

Effect of Coherent Nanoprecipitate on Strain Hardening of Al Alloys: Breaking through the Strength-Ductility Trade-Off.

So-called strength-ductility trade-off is usually an inevitable scenario in precipitation-strengthened alloys. To address this challenge, high-density coherent nanoprecipitates (CNPs) as a microstructure effectively promote ductility though multiple interactions between CNPs and dislocations (i.e., coherency, order, or Orowan mechanism). Although some strain hardening theories have been reported for individual strengthening, how to increase, artificially and quantitatively, the ductility arising from cooperative strengthening due to the multiple interactions has not been realized. Accordingly, a dislocation-based theoretical framework for strain hardening is constructed in terms of irreversible thermodynamics, where nucleation, gliding, and annihilation arising from dislocations have been integrated, so that the cooperative strengthening can be treated through thermodynamic driving force ∆G and the kinetic energy barrier. Further combined with synchrotron high-energy X-ray diffraction, the current model is verified. Following the modeling, the yield stress σy is proved to be correlated with the modified strengthening mechanism, whereas the necking strain εn is shown to depend on the evolving dislocation density and, essentially, the enhanced activation volume. A criterion of high ∆G-high generalized stability is proposed to guarantee the volume fraction of CNPs improving σy and the radius of CNPs accelerating εn. This strategy of breaking the strength-ductility trade-off phenomena by controlling the cooperative strengthening can be generalized to designing metallic structured materials.

A Study to Compare the Effectiveness of McKenzie Neck Exercise and Contract Relax Stretching in Mechanical Neck Pain

Background: Mechanical neck pain is commonly defined as pain between the superior nuchal line and an imaginary transverse line through the tip of the first thoracic spinous process, extending laterally to the sagittal planes peripheral to the lateral borders of the neck. Neck pain (NP) can be local and/or referred into the head and/or upper limbs. NP is a prevalent musculoskeletal issue worldwide, similar to low back pain (LBP), characterized by episodic occurrences with high recurrence and chronicity rates. It frequently arises insidiously and is multifactorial in origin, with modifiable factors including smoking, poor posture, anxiety, depression, neck strain, and occupational activities. NP is a significant societal burden, particularly prevalent among office workers and computer users. Objective: The objective of this study was to compare the effectiveness of McKenzie neck exercises and contract-relax stretching in alleviating mechanical neck pain. Methods: This quasi-experimental study included 40 participants aged 25 to 50 years from Allied Hospital Faisalabad, selected using purposive sampling. Participants were divided into two groups of 20 each. Group 1 received McKenzie neck exercises, while Group 2 received contract-relax stretching. Both groups underwent treatment three times per week for 6 to 8 weeks. Pain and functional performance were evaluated using the Numeric Pain Rating Scale (NPRS) and Neck Disability Index (NDI). Statistical analysis was conducted using SPSS version 27.0, with the Wilcoxon signed-rank test applied for within-group comparisons and the Mann-Whitney U test for between-group comparisons. Results: In Group 1 (contract-relax stretching), NPRS scores improved from a mean of 2.56 (SD=0.51) to 2.11 (SD=0.47) (Z=-2.828, p<0.05), and NDI scores improved from a mean of 3.78 (SD=0.55) to 0.73 (SD=0.73) (Z=-3.419, p<0.05). In Group 2 (McKenzie neck exercises), NPRS scores improved from a mean of 2.61 (SD=0.50) to 1.72 (SD=0.57) (Z=-2.828, p<0.01), and NDI scores improved from a mean of 3.22 (SD=0.73) to 2.06 (SD=0.94) (Z=-3.391, p<0.05). Between-group comparisons indicated that Group 2 had significantly greater improvements in NPRS (mean rank 15.47 vs. 21.53, p<0.05) and NDI scores (mean rank 13.86 vs. 23.14, p<0.05). Conclusion: Both McKenzie neck exercises and contract-relax stretching effectively reduced pain and improved function in patients with mechanical neck pain. However, McKenzie neck exercises demonstrated significantly greater improvements in pain relief and functional outcomes. Therefore, McKenzie neck exercises may be preferred for managing mechanical neck pain. Keywords: Mechanical Neck Pain, McKenzie Neck Exercise, Contract-Relax Stretching, Numeric Pain Rating Scale, Neck Disability Index

Variables associated with the prevalence of self-reported work-related musculoskeletal disorders in veterinary laparoscopic surgeons.

To investigate the relationship between physical attributes and difficulty performing laparoscopic maneuvers with the prevalence of self-reported musculoskeletal injury. Online survey. Surgeons (n = 140) with 3 or more years of laparoscopic experience. Electronic survey distributed via LISTSERVEs and Facebook groups. Responses collected included surgeon attributes, presence of musculoskeletal injuries, and surgical practice data. Statistical analysis was performed using the Shapiro-Wilk test, linear regression, logistic regression, and Wilcoxon rank sum tests. A total of 52 of the 140 respondents reported a musculoskeletal injury with 38 specifying at least one injury (72%). Neck strain was the most prevalent reported musculoskeletal injury (18/52, 34.6%), followed by shoulder tendinopathies (16/52, 30.8%), arm/hand tendonitis (8/52, 15.4%), carpal tunnel (7/52, 13.5%), back pain (4/52, 7.7%) and arm/hand arthritis (1/52, 1.9%). Women were significantly more likely to report a musculoskeletal problem than men (p = .011) with the odds of women reporting a musculoskeletal injury 2.59 times greater than men. Women and surgeons with smaller glove sizes were significantly more likely to report shoulder tendonitis (p = .034, p = .1) and neck strain (p = .009, p = .001). Respondents with a musculoskeletal problem experienced significantly more difficulty using rotating cup biopsy forceps (p < .001) and perceived this as difficult a greater amount of time (p = .006). Female surgeons report more musculoskeletal injuries than their male counterparts. Surgeons with musculoskeletal injuries experience more difficulty performing particular laparoscopic maneuvers. Improving ergonomics for women and surgeons with smaller glove sizes must be prioritized to improve surgeon health and laparoscopic instrument use.

Carcass traits and meat quality assessment of two slow-growing chicks strains fed Acheta domesticus larval meal

Presently, there has been a noticeable rise in the consumption of poultry meat within the general population, particularly focusing on poultry sourced from alternative rearing systems as opposed to intensive ones. This study evaluated the impact of incorporating house cricket (Acheta domesticus,AD) larvae meal into the diet of 2 slow-growing chicken strains on their carcass traits and meat quality. A total of 256 one-day-old male chicks were utilized, with 128 belonging to the Red (R) strain and 128 to the Naked Neck (NN) strain. Chicks from each strain were randomly assigned to 16 replicates of 8 chicks each. Eight replicates were allocated to 2 distinct treatments (n=64 chicks/treatment) based on the diet employed: the control treatments for the Red (R-C) and Naked Neck (NN-C) strains were fed soybean meal, while the other 2 treatments were fed AD meal (R-AD and NN-AD). Three different rations were used throughout the growth cycle of the animals, tailored to meet the nutritional needs of the birds. All chickens were slaughtered at 95 d of age, and eight chickens per treatment were randomly chosen to assess carcass traits and meat quality. Near-infrared reflectance spectroscopy (NIRS) was employed to classify meat based on the feed and the chick strain, achieving a correct discrimination of 100% of the samples. The carcass traits exhibited significant alterations due to the inclusion of insect larval meal in the diet, resulting in reduced values across all parameters for chickens consuming AD meal, irrespective of genotype. The pH and cooking losses were generally higher for chicks fed cricket meal, as occurred with moisture. However, protein content was lower in the meat of chicks consuming cricket meal. Fat content showed lower values for NN chickens. There were minimal differences in the fatty acid profile, with lower C18:3n-3 values for chickens fed cricket meal. Therefore, including Acheta domesticus meal in the diets of slow-growing chick strains is a viable alternative to replace soybean meal. It provides meat quality characteristics comparable to those obtained in conventional systems.

The Burden of Back and Neck Strains and Sprains in Professional Baseball Players.

A retrospective case series study. To analyze the epidemiology of diagnoses of back and neck strains and sprains among Major League (MLB) and Minor League (MiLB) Baseball players. Baseball players perform unique sets of repetitive movements that may predispose to neck and back strains and sprains. Data are lacking concerning the epidemiology of these diagnoses in this population. De-identified data on neck/back strains and sprains were collected from all MLB and MiLB teams from 2011 to 2016 using the MLB-commissioned Health and Injury Tracking System database. Diagnosis rates of conditions related to cervical, thoracic, and lumbar musculature and their impact on days missed due to injury, player participation, and season or career-ending status were assessed. Injury rates were reported as injuries per 1000 athlete exposures (AEs). There were 3447 cases of neck/back strains and sprains in professional baseball players from 2011 to 2016. Seven hundred twenty-one of these occurred in MLB versus 2726 in MiLB. Of injuries 136 were season-ending (26 in MLB, 110 in MiLB); 22 were career-ending (2 in MLB, 20 in MiLB). The total days missed were 39,118 (8838 from MLB and 30,280 from MiLB). Excluding season or career-ending injuries, the mean days missed were 11.8 (12.7 and 11.6 in MLB and MiLB, respectively). The median days missed were 4 (3 and 5 in MLB and MiLB, respectively). Combining MLB and MiLB, the pitcher injury rate was 1.893 per 1000 AEs versus 0.743 per 1000 Aes for other position players ( P < 0.0001). There was a high incidence of neck/back strains and sprains in MLB and MiLB players, with nearly 40,000 aggregate days missed in our 6-year study period. The median days missed were lower than the mean days missed, indicating rightward outliers. Pitchers had over double the rates of injuries compared with other position players. Level III.

Designing and Manufacturing an Affordable and Easy to Use Visual Bio Feedback Device to Fix Forward Head Posture: A Pilot Study Involving Female Students

Forward Head Posture (FHP) is when the head leans forward due to factors such as heavy backpacks or poor computer ergonomics. FHP can lead to neck strain and discomfort as well as potential long-term issues such as arthritis. Treatment options include specialized exercises, orthopedic devices, manual therapy, physical exercises, and visual feedback techniques, along with guidance from specialists in physical medicine and rehabilitation. In this study, a visual feedback-based approach was used to address FHP in female students. The study spanned ten days and included a visual feedback group and a control group. The results showed significant improvements in maximum head angle deviation in the visual feedback group compared to the control group; however, there was no significant change in the DFA number, indicating stability in policy control by the central nervous system. The study demonstrated that visual feedback sessions led to immediate benefits, with participants progressively acquiring skills involving the maintenance of proper head positioning. The test results indicated that the neck angle decreased to less than 15 degrees, indicating a return to a normal state. The versatility of the developed affordable and easy-to-use device and the potential for using smartphone motion sensors for similar visual feedback systems are discussed in this paper as well. The study suggests the promising potential of visual feedback in healthcare, including remote monitoring and smartphone-based solutions.

Evaluation of the pattern of neck pain with forward head posture (fhp) among sewing machine operators- A cross-sectional study

One of the very common negative effects experienced by operators and workers of sewing machines is neck pain. The use of sewing machines in a forward-leaning position over an extended period of time contributes to neck strain and promotes bad postures like the Forward Head Posture (FHP). The objective of this study was to determine the prevalence of FHP and neck pain among sewing machine operators in tailors and garment factories of District Swabi, Pakistan. This cross-sectional study was carried out on a total of 223 users of sewing machines while seated (97 women and 126 men). The study was conducted in Swabi District from October 2022 to February 2023. The outcomes were evaluated using a numerical pain rating scale and the Neck Disability Index (NDI). According to the Numerical pain Rating Scale (NPRS) for neck pain, 24 participants (10.8%) reported mild discomfort, 79 participants (35.4%) reported moderate pain, and 120 participants (53.8%) reported severe pain. Only 13.9% (n=31) of the participants (n=192) had a normal head position. The majority of the participants were hunched forward. The NPRS had a mean of 3.43 (± SD 0.49), the NDI mean was 3.43 (± 0.68), and the cranial vertebral angle (CVA) mean was 1.13 (±SD 0.34). According to the findings of the current study, FHP and neck pain are quite common among individuals who use sewing machines, and a large percentage of these people also have FHP and neck discomfort.

Effect of gait types and external weight carrying strategies on the femoral neck strains during stair descent.

Gait and weight carrying method may change the femoral neck load during stair descent. Applying specific gait and weight carrying methods may reduce the femoral neck load during stair descent, which may reduce hip pain, hip pain related falls and fall related fractures for the older population. The purpose of this study was to test the effect of different gait types (step-over-step v.s. step-by-step) and external weight carrying strategies (ipsilateral v.s. contralateral side) on the femoral neck load, discover which method could reduce the femoral neck load effectively. Seventeen healthy adults from 50 to 70 yrs old were recruited. The kinematic and kinetic analysis, musculoskeletal modelling method were used to estimate the joint and muscle loads for the lower extremities. Finite element analysis was used with the femur model to calculate the femoral neck strains during stair descent with different gait types and weight carrying strategies. The compressive strains were reduced for step-by-step gait method than step-over-step (p<0.015, 12.3-17.4% decrease of strains), the tensile strains were significantly increased for the trailing leg of step-by-step than the leading leg (p<0.001, 24.7% increase of strains). Contralateral weight carrying increased compressive and tensile strains than ipsilateral (p<0.001, 9.9-24.5% increase of strains) in most conditions. Applying step-by-step method and avoiding contralateral side weight carrying could be effective to reduce femoral neck strains. These outcomes could be helpful for the older population to reduce the risks of hip pain, femoral neck pain or pain related falls and fractures.

Assessment of chiropractic intervention influence on pain and life quality in cervicogenic headache afflicted office workers: a review

Cervicogenic headache, characterized by referred pain perceived in the head but originating from the cervical spine, is a prevalent non-migraine headache impacting a significant proportion of the global population, particularly office workers. Recent studies have identified a co-occurrence of cervicogenic headaches with neck pain, often exacerbated by long hours of stationary sitting and computer use common in desk jobs. Despite the growing evidence supporting the effectiveness of chiropractic treatment in mitigating head and neck pain, a distinct gap persists in the literature concerning chiropractic interventions specifically targeting office workers suffering from cervicogenic headaches. This review aims to scrutinize the current literature on the effectiveness of chiropractic interventions on pain management and life quality improvement for office workers afflicted with cervicogenic headaches. Specifically, the review will delve into high-velocity, low-amplitude (HVLA) thrust maneuvers, a widely employed strategy in spinal manipulative therapy, an extension of chiropractic treatment. In the context of cervicogenic headaches, the link between the Rectus Capitis Posterior Minor (RCPM) muscle and the Dura Mater, and how neck strains affecting this connection can instigate headaches, will be explored. Through the comprehensive evaluation of existing literature and studies, this review seeks not only to elucidate the potential of chiropractic treatment in improving the life quality of office workers suffering from cervicogenic headaches, but also to stimulate further research in this essential yet under-explored area of study.

Questionnaire Survey on Cervical Spondylosis among Dentists

Introduction:&#x0D; Most patients particularly dentists who present with neck pain have “non‑specific (simple) neck pain, “where symptoms have a postural or mechanical basis. Etiological factors are usually multifactorial, including poor posture, anxiety, depression, neck strain, and sporting or occupational activities. When mechanical factors are prominent, the condition is often referred to as “cervical spondylosis,” although the term is often applied to all non‑specific neck pain. The aim of this study was to find the frequency of neck pain among dentists.&#x0D; Materials and Methods:&#x0D; A cross‑sectional survey was carried out by convenience sampling in different dental hospitals of Chennai. A total of 100 questionnaires were filled by dentists. The data were collected using a questionnaire focusing on back position, travel to clinic, hours of practice, assisting hands during practice, duration of sleep, time spent on electronic gadgets, dizziness or discomfort after work, duration of pain, and if any treatment undergoing. Qualitative variables were represented as percentages and bar charts. Descriptive statistics, that is mean and standard deviation, were used to represent the total score.&#x0D; Results:&#x0D; Neck pain was the most common complaint. Sixty-seven percent were male and 33% were female. Thirty‑four percent are practising dentistry above 20 years, 32% above 15 years, 26% above 10 years, and 8% above 5 years. The position of practice is that 96% of the dentists practise sitting position and the rest 4% practise standing position. About 72% of dentists use electronic gadgets more than 3 h, 18% of dentists use them for 3 h, and 10 of them use.&#x0D; Conclusion:&#x0D; A The frequency of neck pain and neck disability in dentists seemed to be high and is an area that needs further deliberation. The majority of working dentists have musculoskeletal symptoms in the neck.

Neck and shoulder strains under various head flexing positions while standing and sitting with and without back support for male and female smartphone users

This study recruited 30 young participants (15 men and 15 women) to examine the smartphone usage patterns in three postures (standing, supported sitting, and unsupported sitting) and at five head angle (HA) positions (0°-40°). Cervical erector spinae (CES) and upper trapezius (UTZ) muscle activity, neck flexion (NF), gaze angle (GA), viewing distance (VD), and discomfort scores were collected. Results showed that HA and posture almost affected all responses, while CES muscle activity, NF, and VD differed between sexes. Strain in the neck and shoulder region increased with HA increase. Particularly, when the HA exceeded 20°, the discomfort scores considerably increased. Unsupported sitting should be avoided during smartphone use because of relatively poor responses in all variables. However, both standing and supported sitting have their respective benefits. Sex-related differences were typically observed in the standing position, with women tending to have lower NF but higher CES muscle activity compared with men. Practitioner summary: Although smartphones have become daily necessities, the overall quantitative neck and shoulder strain of using smartphones in different postures is rarely evaluated. We suggest that maintaining the HA within 20° is recommended because of relatively low load on the neck and shoulders. An unsupported sitting should be avoided during smartphone use.

Towards ultra-high strength dual-phase steel with excellent damage tolerance: The effect of martensite volume fraction

Ultra-high strength (> 1 GPa) dual-phase (DP) steels have been extensively investigated in literature. Yet, the damage tolerance of these DP steels remains mostly unexplored, whereas this parameter is crucial for the sheet formability and anti-crushing performance. In this work, a medium-Mn DP steel was proposed in order to develop strong but damage-resistant DP steel by refining the microstructure. Ultra-fine grained (< 1 µm) DP steels were obtained by a simple cold rolling and intercritical annealing process. The developed DP steel can achieve an outstanding ultimate tensile strength (UTS) of over 1470 MPa with appreciable elongation to failure (EtF) of over 9 % when the martensite volume fraction (Vm) is 55 %. Higher Vm results in higher strength. However, the fracture strain, which is connected with damage tolerance, decreases significantly with increasing Vm, and it is even much lower than that of a full-martensite steel. Furthermore, the necking behaviour transfers from diffuse plus localized necking to diffuse necking with increasing Vm. The sufficient ferrite content in the proposed DP1470 steel enables void growth after nucleation, consequently leading to the occurrence of localized necking and higher fracture strain. Thus, a moderate Vm ranging from 45 % to 65 % is suggested for the development of a 1470 MPa grade DP steel with excellent damage tolerance.

Local strain evolution and microstructural characterisation of hydrogen-induced damage at different strain rates in dual phase (DP 780) steel

Effect of strain rate on the damage behaviour of hydrogen (H)-charged dual phase (DP 780) steel via the in-situ digital image correlation (DIC) technique is investigated in this work. Since stress concentration sites like notches are common in engineering practice, two types of uniaxial tensile tests have been carried out using smooth and notch tensile specimens for detailed analysis. The study reveals the significance of hydrogen embrittlement in DP 780 steel, as no strain rate effect is observed on the mechanical property in the case of an uncharged smooth tensile specimen. However, a significant effect of strain rate is detected after the H-charging. Hydrogen showed a lesser ability to aid the failure process when the applied strain rate is raised, as it could diffuse over a limited distance during the tensile test. The local axial and width strains, along with necking and fracture strains, are quantified for each specimen to understand the strain rate effect better. A centre-line crack is observed in every H-charged specimen's fracture surface owing to the presence of MnS inclusion in DP steel along the central line and its interaction with the atomic hydrogen. Moreover, the degree of hydrogen embrittlement is substantially higher in the notch tensile specimens than in the smooth ones.

Study of the Impact of Physiological Artifacts on SSVEP Acquisition

Steady state visually evoked potentials (SSVEPs) are recorded from the visual cortex and are widely used for brain-computer interfaces. Artifacts caused by muscle activity (EMG) and eye movements (EOG) can reach several millivolts, while brain activity signals (EEG) have only several microvolts. EEG signals can be distorted by various types of artifacts. The authors are not aware of any works that have assessed the impact of such artifacts on the registration of SSVEP. In this article, we examined the influence of different types of artifacts on the power of the EEG signal recorded from the visual cortex. Artifacts were recorded from twelve participants using eight EMG/EOG and eight EEG electrodes. We also identified the locations where it is worth recording EOG/EMG signals to use them to remove artifacts. Our results show that neck strain, swallowing, jaw clenching, and wincing are the most disruptive artifacts for SSVEP.

Modeling the strain localization of shell elements subjected to combined stretch–bend loads: Application on automotive sheet metal stamping simulations

This study presents a modeling approach for predicting strain localization during sheet metal stamping processes focused on automotive engineering applications. The so-called stretching-to-bending ratio, ρ, is proposed to characterize the loading conditions acting on an element during stamping processes. Then, localized strain or necking strain is suggested to be a function of ρ. Different stretch–bending tests with different tool radii, i.e., R3, R6, R10, and R50 are conducted for two automotive sheet metals, DP800 and AA6010, to identify their forming limits under combined stretch–bend loads. The calibrated necking limit curve of the AA6016 sheet is then employed in AutoForm R10 software to predict the necking and failure of a stamped panel. Agreement with the experimental observation of failure positions of the panel validates the usefulness of the proposed modeling approach in practice.

V04-06 ROBOTIC ASSISTED TRANS-VESICOSCOPIC URETERIC REIMPLANTATION IN CHILDREN: SURGICAL ERGONOMICS RELATED TO MUSCULOSKELETAL SYMPTOMS

You have accessJournal of UrologyCME1 Apr 2023V04-06 ROBOTIC ASSISTED TRANS-VESICOSCOPIC URETERIC REIMPLANTATION IN CHILDREN: SURGICAL ERGONOMICS RELATED TO MUSCULOSKELETAL SYMPTOMS MS Ansari, Prabhu Karunakaran, Sanjoy Sureka, and Priyank Yadav MS AnsariMS Ansari More articles by this author , Prabhu KarunakaranPrabhu Karunakaran More articles by this author , Sanjoy SurekaSanjoy Sureka More articles by this author , and Priyank YadavPriyank Yadav More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003252.06AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Robot-assisted surgery has been reported to provide many benefits over open surgeries to the patient and surgeon. Many surgeons experience work-related pain and musculoskeletal symptoms. Neck strain, back strain/pain and lower extremity exertion have been reported up to 20-40% of the surgeons in open surgeries. We sought to evaluate the feasibly of robotic assisted trans-vesicoscopic ureteric reimplantation in children and surgeons' work-related musculoskeletal symptoms in comparison to open surgery METHODS: The children under 12 years of age with vesicoureteric reflux (VUR underwent open) (Group I) and vesicoscopic robotic assisted ureteric reimplantation (VRAUR) (Group II). All surgeries were performed by a single surgeon. For VRAUR the patient was placed in a dorsal lithotomy position. Four ports (Two 8-mm working ports were placed in a straight line drawn along the anterior superior iliac spine and one endoscopic [middle]) 12 mm (Intuitive Surgical, Sunnyvale, CA), was placed 2 cm above the same line and the fourth assistant port of 3 mm was placed 2 cm below the line. The surgeons related ergonomic parameters recorded in both the groups were generalised pain, neck and back strain/pain along with lower extremity exertion to surgeons (assessed as per visual analogue scale [VAS]). Success was defined as the absence of VUR on direct radionuclide cystogram at 12 weeks. RESULTS: The median age of the children was 4.5 and 5.1 in groups I and II respectively. Both the groups had 30 of patients each. The grades of VUR was comparable in both the groups. The VRAUR procedure could be accomplished in all the cases without any slippage of robotic ports or clashing of arms except in 2-year-old that without any conversion. The 2-yr-old child with bladder capacity of 150 cc posed little difficulty due to space restriction and slight clashing of arms that lengthened the procedure but could be completed successfully. The mean operative time was 95 (90-122) and 140 (115-160) minutes (p=0.029) in groups I and II respectively with a successes rate of 96.7 and 93.3 (p=0.031) respectively. The Surgeons’ musculoskeletal VAS scores recorded were substantially more in Group I as compared to Group II (p value 0.03, OR 3.9 [1.9-5.4]). CONCLUSION: Robotic assisted laparoscopic ureteral reimplantation is feasible and offers success rate comparable to open surgery. The surgical ergonomics related to musculoskeletal symptoms are more substantial in open surgery. Source of Funding: None © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e339 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information MS Ansari More articles by this author Prabhu Karunakaran More articles by this author Sanjoy Sureka More articles by this author Priyank Yadav More articles by this author Expand All Advertisement PDF downloadLoading ...