Pityriasis rosea: dermoscopic features in Uganda

PURPOSE

The study aimed to describe the dermoscopic features of pityriasis rosea among patients attending the skin clinic at Mbarara Regional Referral Hospital.

PATIENTS AND METHODS

A hospital-based cross-sectional descriptive study conducted for a 6-month period in the skin clinic of MRRH in Southwestern Uganda. Data were collected from consecutively recruited patients using structured questionnaires. Patients with a clinical diagnosis of pityriasis rosea were examined using a dermoscope and subsequently sent for KOH and TPHA tests to rule out fungal skin infection and secondary syphilis, respectively, and then received routine care at the skin clinic.

RESULTS

There were 54 patients with pityriasis rosea seen. Dermoscopy was done on a total of 162 lesions of which 19 were herald patches, 51 were truncal lesions, 52 on the extremities while 40 were on the face and neck regions. Common dermoscopic features consisted of a violaceous background noted in 145 (89.51%), white scales in 161 (99.38%), diffuse scale distribution in 57 (35.19%), perifollicular scale type in 61 (37.65%), and brown-dotted pigmentary changes in 66 (40.74%). Other unique findings noted in a few lesions were cloudy structures, petechial spots, erosions, and punched out pits.

CONCLUSION

Most prevalent dermoscopic features included: a violaceous background, white scales, diffuse scale distribution, perifollicular scale type, brown-dotted pigmentary changes with no visible blood vessels nor follicular changes. Other unique less frequently seen findings were cloudy structures, petechial spots, erosions, and punched out pits.

A cluster-based law enforcement body armor sizing system: Concept, procedure, and design practice

Given the evolution of human body dimensions, the increasing diversity within the law enforcement workforce, the growing risks of assault faced by law enforcement officers (LEOs), and the absence of a national standard for body armor sizing, there is a critical need to explore LEO body size classification. This exploration will facilitate the development of an armor sizing structure that adequately accommodates the current LEO population. This study aimed to address this need by developing a LEO body armor sizing scheme and creating a sizing chart/app. Additionally, a plan was devised for a series of 'sizing vests' that would enhance LEO armor accommodation and facilitate fit assessment. Torso anthropometric data pertaining to body armor sizing were collected from 756 male and 218 female LEOs across different regions of the United States. Based on the collected data, a nine-size system for male LEOs and an eight-size scheme for female LEOs were suggested. Furthermore, a sizing chart/app was proposed to enable LEOs to swiftly identify an armor size that is most likely to fit an individual, considering a few anthropometric characteristics known to LEOs. To supplement the sizing chart/app, a series of 'sizing vests' were recommended. These vests would provide LEOs with a physical means to assess and determine the best-fitting armor size, offering an alternative to relying solely on the sizing chart/app. We recommend that armor manufacturers adopt these new sizing systems and create prototypes of armor that can be evaluated within this sizing structure. This evaluation process will facilitate improved fit and enhanced protection for LEOs.

Dysphagia lusoria caused by aberrant right subclavian artery associated with truncus bicaroticus in an 8-month-old girl. Case report and review of literature

Dysphagia lusoria is a rare pediatric condition caused by extrinsic compression of the esophagus by an abnormal subclavian artery. The most common congenital abnormality in aortic arch development is an aberrant right subclavian artery. The retroesophageal right subclavian artery is typically symptomatic in 10-33% of cases. The patient, an 8-month-old girl with a history of early dysphagia and stridor, was diagnosed with an abnormal right subclavian artery. She was admitted to the pneumology service multiple times due to stridor, vomiting, and failure to thrive. During hospitalization at the gastroenterology service, a barium swallow and an upper digestive endoscopy indicated an abnormal right subclavian artery, which was confirmed by an Angiography CT scan. She underwent surgery at the age of sixteen months. All symptoms are resolved following surgical intervention, and the patient is still asymptomatic and in good clinical condition 12 months later. Every physician should be aware of abnormal right subclavian arteries and their clinical symptoms in children and adults in order to recognize and diagnose them early. Only an early evaluation may reduce complications such as delayed physical growth, dysphagia, and recurrent respiratory infections.

Vehicle front-end geometry and in-depth pedestrian injury outcomes

OBJECTIVE

Large passenger vehicles have consistently demonstrated an outsized injury risk to pedestrians they strike, particularly those with tall, blunt front ends. However, the specific injuries suffered by pedestrians in these crashes as well as the mechanics of those injuries remain unclear. The current study was conducted to explore how a variety of vehicle measurements affect pedestrian injury outcomes using crash reconstruction and detailed injury attribution.

METHODS

We analyzed 121 pedestrian crashes together with a set of vehicle measurements for each crash: hood leading edge height, bumper lead angle, hood length, hood angle, and windshield angle.

RESULTS

Consistent with past research, having a higher hood leading edge height increased pedestrian injury severity, especially among vehicles with blunt front ends. The poor crash outcomes associated with these vehicles stem from greater injury risk and severity to the torso and hip from these vehicles' front ends and a tendency for them to throw pedestrians forward after impact.

CONCLUSIONS

The combination of vehicle height and a steep bumper lead angle may explain the elevated pedestrian crash severity typically observed among large vehicles.

Association of anthropometric characteristics of law enforcement officers with perceived ratings of fit, comfort, and pain in the use of body armor

Knowledge gaps exist on association between law enforcement officer (LEO) anthropometric characteristics and perceived body armour fit, armour discomfort, and armour-caused pain. This study assessed the correlation and identified influential torso dimensions for armour sizing and design applications. Nine-hundreds and seventy-four LEOs across the U.S. participated in a national study on LEO armour use and body dimensions. Perceived ratings of armour fit, armour discomfort, and body pain were found moderately correlated with each other. In addition, armour fit ratings were associated with certain torso anthropometric characteristics, such as chest circumference, chest breadth, chest depth, waist circumference, waist breadth (sitting), waist front length (sitting), body weight, and body mass index. LEOs who reported armour poor fit, armour discomfort, and armour-caused pain had a larger mean of body dimensions than the "armor good fit" group. More women than men had poor fit, discomfort, and body pain in the use of body armour.Practitioner summary: The identified influential body measurements can be used as the "drivers" for multivariate analyses to develop an improved armour sizing system to further LEO protection. The study also suggests consideration of gender specific armour sizing systems to accommodate differences in torso configurations between male and female officers and to resolve the concern that more female officers had poor armour fit than male officers.

Annular Pigmented Macules on the Upper Trunk: A Quiz

Abstract is missing (Quiz)

Torso hemorrhage: noncompressible? never say never

Since limb bleeding has been well managed by extremity tourniquets, the management of exsanguinating torso hemorrhage (TH) has become a hot issue both in military and civilian medicine. Conventional hemostatic techniques are ineffective for managing traumatic bleeding of organs and vessels within the torso due to the anatomical features. The designation of noncompressible torso hemorrhage (NCTH) marks a significant step in investigating the injury mechanisms and developing effective methods for bleeding control. Special tourniquets such as abdominal aortic and junctional tourniquet and SAM junctional tourniquet designed for NCTH have been approved by FDA for clinical use. Combat ready clamp and junctional emergency treatment tool also exhibit potential for external NCTH control. In addition, resuscitative endovascular balloon occlusion of the aorta (REBOA) further provides an endovascular solution to alleviate the challenges of NCTH treatment. Notably, NCTH cognitive surveys have revealed that medical staff have deficiencies in understanding relevant concepts and treatment abilities. The stereotypical interpretation of NCTH naming, particularly the term noncompressible, is the root cause of this issue. This review discusses the dynamic relationship between TH and NCTH by tracing the development of external NCTH control techniques. The authors propose to further subdivide the existing NCTH into compressible torso hemorrhage and NCTH' (noncompressible but REBOA controllable) based on whether hemostasis is available via external compression. Finally, due to the irreplaceability of special tourniquets during the prehospital stage, the authors emphasize the importance of a package program to improve the efficacy and safety of external NCTH control. This program includes the promotion of tourniquet redesign and hemostatic strategies, personnel reeducation, and complications prevention.

Breaking point? An analysis of fatal stab wounds to the torso in Ireland between 2011 and 2018, examining the extent of rib fractures

This study examines the pattern of rib injuries occurring in cases of fatal torso stab wounds in Ireland between 2011 and 2018. It has been suggested by previous studies that rib fractures are not commonly sustained in stab wounds to the torso. We wanted to ascertain whether this was the case, as our data suggested that rib fractures were frequent, and where a rib is fractured there is a higher chance of organ injury and death, making this an important area of study. One hundred and forty seven cases of fatal stab wounds from an eight-year period were retrospectively reviewed. Fatal stab wounds to other body areas, were excluded; leaving a total of 104 cases with stab wounds to the torso. We found that 69.2% of cases had rib injuries, a figure significantly higher than previously reported. Our data suggests that stab wounds to the torso often fracture ribs, putting the underlying organs at increased risk of injury and perhaps contributing to fatality. The amount of force needed to cause a rib fracture can be difficult to quantify and indeed from the high percentage of rib fractures sustained in our data it appears that the ribs may be fractured regardless of the amount of force used; this is borne out by the finding that self-inflicted injuries also caused rib fractures. Our study shows that other factors, such as anatomical positioning and wound depth may have a greater bearing than force in terms of whether a rib fracture is sustained.

Pedicle screw path planning for multi-level vertebral fixation

BACKGROUND

For the spinal internal fixation procedures, connecting rods to the pedicle screws are commonly used in all spinal segments from the cervical to sacral spine. So far, we have only seen single vertebral screw trajectory planning methods in literatures. Joint screw placements in multi-level vertebrae with the constraint of an ipsilateral connecting rod are not considered.

PURPOSE

In this paper, a screw trajectory planning method that considers screw-rod joint system with both multi-level vertebral constraints and individual vertebral safety tolerance are proposed.

METHODS

The proposed method addresses three challenging constraints jointly for multi-level vertebral fixation with pedicle screws. First, a cylindrical screw safe passage model is suggested instead of a unique mathematical optimal trajectory for a single pedicle. Second, the flexible screw cap accessibility model is also included. Third, the connecting rod is modeled to accommodate the spine contour and support the needed gripping capacity. The retrospective clinical data of relative normal shape spines from Beijing Jishuitan hospital were used in the testing. The screw trajectories from the existing methods based on single vertebra and the proposed method based on multi-level vertebrae optimization are calculated and compared.

RESULTS

The results showed that the calculated screw placements by the proposed method can achieve 88% success rate without breaking the pedicle cortex and 100% in clinical class A quality (allow less than 2 mm out of the pedicle cortex) compared to 86.1% and 99.1%, respectively, with the existing methods. Expert evaluation showed that the screw path trajectories and the connecting rod calculated by the new method satisfied the clinical implantation requirements.

CONCLUSIONS

The new screw planning approach that seeks an overall optimization for multi-level vertebral fixation is feasible and more advantageous for clinical use than the single vertebral approaches.

Ultrasound-guided procedures for the management of chronic thoracic back pain: a technical review

Pain arising from the thoracic region has been reported to be potentially as debilitating as cervical or lumbar back pain, and may stem from a vast number of spinal sources, including zygapophysial, costovertebral and costotransverse joints, intervertebral discs, ligaments, fascia, muscles, and nerve roots. Over the last two decades, the use of ultrasound in interventional spinal procedures has been rapidly evolving, due to the ultrasound capabilities of visualizing soft tissues, including muscle layers, pleura, nerves, and blood vessels, allowing for real-time needle tracking, while also reducing radiation exposure to both patient and physician, when compared to traditional fluoroscopy guidance. However, its limitations still preclude it from being the imaging modality of choice for some thoracic spinal procedures, notably epidural (interlaminar and transforaminal approaches) and intradiscal injections. In this technical review, we provide an overview of five thoracic spinal injections that are amenable to ultrasound guidance. We start by discussing their clinical utility, followed by the relevant topographic anatomy, and then provide an illustrated technical description of each of the procedures discussed: (1) erector spinae plane block; (2) intra-articular thoracic zygapophyseal (facet) joint injection; (3) thoracic medial branch block; (4) costotransverse joint injection; and (5) costovertebral joint injection.

A Novel Liver Cancer POC Diagnostic Detection Technique by a Gate-engineered Source-extended TFET Device

This work reports a novel POC diagnostic technique to identify the cancerous liver cell lines by designing a Source-Extended (SE) Tunnel Field Effect Transistor (TFET) having a Single-Gate (SG) with Single-Metal (SM) and Dual-Metal (DM) structure. The proposed structures have been equipped with nanocavities by trenching the gate oxide layer where the needle biopsy obtained liver sample has been immobilized. The detection is based on the difference in drain current and the ratio of the proposed device's ON and OFF state currents, which has been evaluated by obtaining the sensitivities. The cancerous and non-cancerous liver cell lines possess different dielectric properties in high frequencies ranging from 100 MHz to 5 GHz, affecting the cavity region's effective capacitances. The change in the dielectric constant of the specimen at 900 MHz has been considered which results in the change in device drain current and device performance. Various parameters of the device, like the adhesive layer in the cavity region, the material of the gate, the length of the cavities, and the orientation of the cavities, have been modified to observe the performance. The total work has been done in the simulation environment, which includes the study considering the different proportions of cancerous and non-cancerous cells in a particular specimen. A comparative analysis has been made between the performance of the proposed SM and DM gate structure. The proposed detection method has been compared with the existing methods reported in the literature. The proposed method can be considered a novel technique and can be implemented as a point of care (POC) diagnostic to detect whether the specimen liver cell line is cancerous.

Small Female Occupant Response in Reclined and Upright Seated Postures in Frontal Impacts

The objective of this study was to compare the kinematics of the head-neck, torso, pelvis, and lower extremities and document injuries and their patterns to small female occupants in frontal impacts with upright and reclined postures using an experimental model. Six postmortem human surrogates (PMHS) with a mean stature of 154 ± 9.0 cm and mass of 49 ± 12 kg were equally divided between upright and reclined groups (seatback: 25 deg and 45 deg), restrained by a three-point integrated belt, positioned on a semirigid seat, and exposed to low and moderate crash velocities (15 km/h and 32 km/h respectively). The response between the upright and reclined postures was similar in magnitude and curve morphology. While none of the differences were statistically significant, the thoracic spine demonstrated increased downward (+Z) displacement, and the head demonstrated an increased horizontal (+X) displacement for the reclined occupants. In contrast, the upright occupants showed a slightly increased downward (+Z) displacement at the head, but the torso displaced primarily along the +X direction. The posture angles between the two groups were similar at the pelvis and different at the thorax and head. At 32 km/h, both cohorts exhibited multiple rib failure, with upright specimens having a greater number of severe fractures. Although MAIS was the same in both groups, the upright specimens had more bi-cortical rib fractures, suggesting the potential for pneumothorax. This preliminary study may be useful in validating physical (ATDs) and computational (HBMs) surrogates.

Time-of-flight scatter rejection in x-ray radiography

Objective.Time-of-flight (TOF) scatter rejection allows for identifying and discarding scattered photons without the use of an anti-scatter grid (ASG). Although TOF scatter rejection was initially presented for cone-beam computed tomography, we propose, herein, to extend this approach to x-ray radiography. This work aims to evaluate with simulations if TOF scatter rejection can outperform ASGs for radiography.Approach.GATE was used to simulate the radiography of a head and a torso and a water cylinder with bone inserts in a system with total timing jitters from 0 ps up to 500 ps full-width-at-half-maximum. The transmission factor of TOF scatter rejection for primary and scattered photons was evaluated as if it were a virtual ASG.Main results.With a total timing jitter of 50 ps, TOF scatter rejection can reach a selectivity of 4.93 with a primary photons transmission of 99%. Reducing the timing jitter close to 0 ps increases the selectivity up to 15.85 for a head and torso radiography, outperforming typical ASGs which usually have a selectivity from 2.5 to 10 with a primary photons transmission from 50% to 70%.Significance.This suggests that TOF scatter rejection may be suitable to replace ASGs in applications requiring lower radiation exposure if sufficiently low timing jitter is achieved.

Advanced Non-compressible Torso Hemorrhage Management is Combat Casualty Care's Moon Shot

Non-compressible torso hemorrhage continues to cause considerable preventable mortality on the battlefield. In this editorial, we highlight the burden of deaths, the most at-risk torso structures, current interventions, and their limitations and recommendations for future research and device development.

Effect of forward moment on recovery motion against tripping

Investigating the fall recovery motion mechanism is crucial to prevent fall injuries. Among the various parameters of motion and posture, the forward moment can be considered the representative parameter of the magnitude of tripping from a kinematic perspective. The effect of increasing the forward moment on the recovery motion after tripping was investigated in this study. A tripping experiment was performed on a treadmill, and the recovery motion was observed. The forward moment was artificially increased using several approaches, such as pulling the torso, increasing gait speed, and increasing body mass. Factor analysis was performed to establish the relationship between the recovery motion parameters and forward moment. The distribution of the factor scores implied the uniqueness of the recovery motion of the pull condition. Although the forward moment temporarily increased, it was compensated quickly. The other conditions and factors indicated qualitative similarity of the recovery motion among the different conditions. This study demonstrates that the recovery motion after tripping is robust against an increase in forward moment, regardless of the method used to increase the forward moment. The investigation of reaction motion pattern enables validation of the recovery motion and falling posture estimation. Such fall simulations will facilitate the development of a method of fall prevention and mitigation.

Optimisation of the upper body motion for production of the bat-head speed in baseball batting

The purposes of this study were to 1) develop a simulation model of baseball batting utilising the standard motion, and 2) explore optimal motions of the upper body to increase the bat-head speed. Twenty-three male collegiate baseball players performed tee batting set at waist height. A ten-segment angle-driven simulation model consisting of a bat and upper body was driven using with the coordinate data of the standard motion. Performance optimisation was conducted to find joint angle time histories of the upper body that increase the maximum bat-head speed. In the evaluation of the simulation model, the root mean square error between the measured and simulation model was 0.19 m/s and 0.98° for the time histories of the bat-head speed and bat orientation angle. Performance optimisation was able to achieve a targeted increase in bat-head speed (35.6 m/s to 40.0 m/s) through greater barrel-side shoulder abduction, knob-side elbow flexion, and torso right lateral flexion around ball impact resulted in the bat accelerating in the hitting direction. It is concluded that the proposed simulation approach can be applied as a tool for further simulation analysis in various complex sporting motions.

Relationship between coordination variability and Osgood-Schlatter disease in male junior youth soccer players -cross-sectional study using an inertial measurement unit

BACKGROUND

Osgood-Schlatter disease is a common overuse injury, and motor coordination is discussed as a risk factor; however, no reports have examined motor coordination in young soccer players with Osgood-Schlatter disease. This study aimed to investigate the difference in motor coordination between Osgood-Schlatter disease-affected and non-affected soccer players on a junior youth soccer team.

METHODS

This cross-sectional study investigated 35 young soccer players of 12-15 years of age, who completed a self-administered questionnaire covering general information, injury history, and athletic experience. An inertial measurement unit was attached to the participant's thoracic spine, lumbar spine, pelvis, thigh, and lower leg. The sagittal plane tilt angle of each body segment during squatting was analyzed. The continuous relative phase was calculated using the sagittal plane tilt angle. The mean absolute relative phase and continuous relative phase variabilities were calculated and compared between Osgood-Schlatter disease-affected and non-affected players.

FINDINGS

The sagittal plane tilt angle of each body segment during static standing and maximum flexion did not differ between the two groups. However, the Osgood-Schlatter disease group had significantly less continuous relative phase variability between the lumbar spine and pelvis (P < 0.01, Cohen's d = 0.91). The Osgood-Schlatter disease group had significantly fewer participants with other sports experience (P = 0.032, φ = 0.36).

INTERPRETATION

Dysfunctional lower trunk and hip muscles may be leading to Osgood-Schlatter disease. It is suggested that a variety of physical activities should be performed in the junior age group to allow players to acquire a variety of movement patterns.

Information content and temporal structure of face selective local field potentials frequency bands in IT cortex

Sensory stimulation triggers synchronized bioelectrical activity in the brain across various frequencies. This study delves into network-level activities, specifically focusing on local field potentials as a neural signature of visual category representation. Specifically, we studied the role of different local field potential frequency oscillation bands in visual stimulus category representation by presenting images of faces and objects to three monkeys while recording local field potential from inferior temporal cortex. We found category selective local field potential responses mainly for animate, but not inanimate, objects. Notably, face-selective local field potential responses were evident across all tested frequency bands, manifesting in both enhanced (above mean baseline activity) and suppressed (below mean baseline activity) local field potential powers. We observed four different local field potential response profiles based on frequency bands and face selective excitatory and suppressive responses. Low-frequency local field potential bands (1-30 Hz) were more prodominstaly suppressed by face stimulation than the high-frequency (30-170 Hz) local field potential bands. Furthermore, the low-frequency local field potentials conveyed less face category informtion than the high-frequency local field potential in both enhansive and suppressive conditions. Furthermore, we observed a negative correlation between face/object d-prime values in all the tested local field potential frequency bands and the anterior-posterior position of the recording sites. In addition, the power of low-frequency local field potential systematically declined across inferior temporal anterior-posterior positions, whereas high-frequency local field potential did not exhibit such a pattern. In general, for most of the above-mentioned findings somewhat similar results were observed for body, but not, other stimulus categories. The observed findings suggest that a balance of face selective excitation and inhibition across time and cortical space shape face category selectivity in inferior temporal cortex.

Non-compressible truncal and junctional hemorrhage: A retrospective analysis quantifying potential indications for advanced bleeding control in Dutch trauma centers

BACKGROUND

Truncal and junctional hemorrhage is the leading cause of potentially preventable deaths in trauma patients. To reduce this mortality, the application of advanced bleeding control techniques, such as resuscitative endovascular balloon occlusion of the aorta (REBOA), junctional tourniquets, Foley catheters, or hemostatic agents should be optimized. This study aimed to identify trauma patients with non-compressible truncal and junctional hemorrhage (NCTJH) who might benefit from advanced bleeding control techniques during initial trauma care. We hypothesized that there is a substantial cohort of Dutch trauma patients that can possibly benefit from advanced bleeding control techniques.

METHODS

Adult trauma patients with an Abbreviated Injury Scale ≥3 in the torso, neck, axilla, or groin region, who were presented between January 1st, 2014 and December 31st, 2018 to two Dutch level-1 trauma centers, were identified from the Dutch Trauma Registry. Potential indications for advanced bleeding control in patients with NCTJH were assessed by an expert panel of three trauma surgeons based on injury characteristics, vital signs, response to resuscitation, and received treatment.

RESULTS

In total, 1719 patients were identified of whom 249 (14.5 %) suffered from NCTJH. In 153 patients (60.6 %), hemorrhagic shock could have been mitigated or prevented with advanced bleeding control techniques. This group was younger and more heavily injured: median age of 40 versus 48 years and median ISS 33 versus 22 as compared to the entire cohort. The mortality rate in these patients was 31.8 %. On average, each of the included level-1 trauma centers treated an NCTJH patient every 24 days in whom a form of advanced bleeding control could have been beneficial.

CONCLUSIONS

More than half of included Dutch trauma patients with NCTJH may benefit from in-hospital application of advanced bleeding control techniques, such as REBOA, during initial trauma care. Widespread implementation of these techniques in the Dutch trauma system may contribute to reduction of mortality and morbidity from non-compressible truncal and junctional hemorrhage.

Prediction of trunk muscle activation and spinal forces in adolescent idiopathic scoliosis during simulated trunk motion: A musculoskeletal modelling study

Due to lack of reference validation data, the common strategy in characterizing adolescent idiopathic scoliosis (AIS) by musculoskeletal modelling approach consists in adapting structure and parameters of validated body models of adult individuals with physiological alignments. Until now, only static postures have been replicated and investigated in AIS subjects. When aiming to simulate trunk motion, two critical factors need consideration: how distributing movement along the vertebral motion levels (lumbar spine rhythm), and if neglecting or accounting for the contribution of the stiffness of the motion segments (disc stiffness). The present study investigates the effect of three different lumbar spine rhythms and absence/presence of disc stiffness on trunk muscle imbalance in the lumbar region and on intervertebral lateral shear at different levels of the thoracolumbar/lumbar scoliotic curve, during simulated trunk motions in the three anatomical planes (flexion/extension, lateral bending, and axial rotation). A spine model with articulated ribcage previously developed in AnyBody software and adapted to replicate the spinal alignment in AIS subjects is employed. An existing dataset of 100 subjects with mild and moderate scoliosis is exploited. The results pointed out the significant impact of lumbar spine rhythm configuration and disc stiffness on changes in the evaluated outputs, as well as a relationship with scoliosis severity. Unfortunately, no optimal settings can be identified due to lack of reference validation data. According to that, extreme caution is recommended when aiming to adapt models of adult individuals with physiological alignments to adolescent subjects with scoliotic deformity.

Can intermittent changes in trunk extensor muscle length delay muscle fatigue development?

Muscle length changes may evoke alternating activity and consequently reduce local fatigue and pain during prolonged static bending. The aim of this study was to assess whether a postural intervention involving intermittent trunk extensor muscle length changes (INTERMITTENT) can delay muscle fatigue during prolonged static bending when compared to a near-isometric condition (ISOMETRIC) or when participants were allowed to voluntarily vary muscle length (VOLUNTARY). These three conditions were completed by 11 healthy fit male participants, in three separate sessions of standing with 30 ± 3 degrees trunk inclination until exhaustion. Conventional and high-density electromyography (convEMG and HDsEMG, respectively) were measured on the left and right side of the spine, respectively. The endurance time for INTERMITTENT was 33.6% greater than ISOMETRIC (95% CI: [3.8, 63.5]; p = 0.027) and 29.4% greater than VOLUNTARY (95% CI: [7.0, 51.7]; p = 0.010), but not different between ISOMETRIC and VOLUNTARY. The convEMG and HDsEMG amplitude coefficient of variation was significantly greater for INTERMITTENT versus ISOMETRIC. The rate of change in convEMG and HDsEMG spectral content did not reveal significant differences between conditions as found in endurance time. Additional regression analyses between endurance time and rate of change in convEMG (p > 0.05) and HDsEMG (R2 = 0.39-0.65, p = 0.005-0.039) spectral content indicated that HDsEMG better reflects fatigue development in low-level contractions. In conclusion, imposed intermittent trunk extensor muscle length changes delayed muscle fatigue development when compared to a near-isometric condition or when participants were allowed to voluntarily vary muscle length, possibly due to evoking alternating activity between/within trunk extensor muscles.

Thermoregulatory and perceptual implications of varying torso soft armour coverage during treadmill walking in dry heat

Modular armour allows soldiers to adjust the level of coverage according to the threat level. We hypothesized that armour configurations with lower levels of torso soft armour coverage attenuate physiological and perceptual responses during exercise in the heat. Fifteen adults (5 females/10 males, 26 ± 5 years) walked (5 km/h, 1% incline, 1h) in dry heat (38 °C, 20% humidity) while wearing body armour that provided; i) high coverage (HC: 0.57 ± 0.09 m2, 18.5 ± 0.3 kg), ii) moderate coverage (MC: 0.44 ± 0.07 m2, 18.1 ± 0.3 kg), iii) low coverage (LC1: 0.21 ± 0.03 m2, 17.4 ± 0.1 kg), or iv) low coverage with weight equalization (LC2: 0.21 ± 0.03 m2, 18.6 ± 0.2 kg). Core temperature (Tcore), heart rate (HR), metabolic heat production (M-W), whole-body sweat rate (WBSR), and perceptual responses were measured. M-W during exercise (629 ± 126 W) did not differ between configurations (p = 0.30). The change in Tcore (HC: 0.88 ± 0.37 °C, MC: 0.85 ± 0.32 °C, LC1: 0.91 ± 0.38 °C, LC2: 0.89 ± 0.42 °C, p = 0.93), HR (HC: 97 ± 14 bpm, MC: 103 ± 16 bpm, LC1: 96 ± 15 bpm, LC2: 97 ± 20 bpm, p = 0.08), and WBSR (HC: 10.2 ± 3.4 g/min, MC: 10.3 ± 4.3 g/min, LC1: 9.9 ± 4.7 g/min, LC2: 10.4 ± 4.5 g/min, p = 0.84) did not differ between configurations. Perceptual responses did not differ between configurations (all p ≥ 0.15). Reducing torso soft armour coverage, with minimal reductions in armour load, does not reduce physiological or perceptual strain during walking in dry heat.

Emerging innovations and advancements in the treatment of extremity and truncal soft tissue sarcomas

In this special edition update on soft tissue sarcomas (STS), we cover classifications, emerging technologies, prognostic tools, radiation schemas, and treatment disparities in extremity and truncal STS. We discuss the importance of enhancing local control and reducing complications, including the role of innovative imaging, surgical guidance, and hypofractionated radiation. We review advancements in systemic and immunotherapeutic treatments and introduce disparities seen in this vulnerable population that must be considered to improve overall patient care.

Is torso twist production the primary role of the torso muscles in front crawl swimming?

The torso muscles play important roles in longitudinal rotation between the upper and lower torso on land but demands on these muscles at different swimming speeds and their role in torso twist in front crawl remains unclear. We aimed to compare torso muscle activity at different front crawl speeds and to assess the relationships between torso muscle activity and torso twist. Three-dimensional kinematics and torso muscle EMG data were collected from 15 male swimmers during middle-distance and sprint front crawl. Internal oblique, external oblique, and rectus abdominis, but not erector spinae, activities were greater at sprint than middle-distance pace. Sprint swimmers are likely to benefit from focusing training on the abdominal muscles. Cross-correlation peak coefficients between muscle activity and torso twist occurred with 517-775 and 400-600 ms lag at middle-distance and sprint paces (respectively). These lags are beyond the torso muscle electromechanical delay (~220 ms) and are too long for these muscles to produce movement changes. Further, peak coefficients coincided with both positive and negative shifts, indicating that muscle activity did not always precede kinematic changes. The torso muscles are therefore likely to play a greater role in maintaining stability and controlling posture in front crawl than producing torso twist.

Acoustic Characterization Study of Beef Loins Using Ultrasonic Transducers

The objective of this study was to non-destructively characterize samples of fresh beef loin by low-intensity ultrasound inspection at various frequencies and to correlate the acoustic parameters of these inspections with quality parameters. In this regard, ultrasonic parameters such as ultrasound pulse velocity (UPV) and variables related to attenuation and frequency components obtained from fast Fourier transform (FFT) were considered. For this, pulsed ultrasonic signal transducers with a frequency of 0.5 and 1.0 MHz were used. Acoustic parameters and those obtained through traditional instrumental analyses (physicochemical and texture) underwent a Pearson correlation analysis. The acoustic determinations revealed numerous significant correlations with the rest of the studied parameters. The results demonstrate that ultrasonic inspection has the ability to characterize samples with a non-destructive nature, and likewise, this methodology can be postulated as a promising predictive tool for determining quality parameters in beef loin samples.

Trunk resistance to mechanical perturbations, associations with low back pain, pain-related cognitions and movement precision

BACKGROUND

Pain-related cognitions are associated with motor control changes in people with chronic low-back pain (CLBP). The mechanism underlying this association is unclear. We propose that perceived threat increases muscle-spindle-reflex-gains, which reduces the effect of mechanical perturbations, and simultaneously decreases movement precision.

AIM

To evaluate effects of CLBP and pain-related cognitions on the impact of mechanical perturbations on trunk movement, and associations between these perturbation effects and movement precision.

METHODS

30 participants with CLBP and 30 healthy controls, performed two consecutive trials of a seated repetitive reaching task. During both trials participants were warned for mechanical perturbations, which were only administered during the second trial. The perturbation effect was characterized by the deviation of the trajectory of the T8 vertebra relative to the sacrum. Trunk movement precision was expressed as tracking error during a trunk movement target tracking task. We assessed pain-related cognitions with the task-specific 'Expected Back Strain'-scale (EBS). We used a two-way-Anova to assess the effect of Group (CLBP vs back-healthy) and dichotomized EBS (higher vs lower) on the perturbation effect, and a Pearson's correlation to assess associations between perturbation effects and movement precision.

FINDINGS

Higher EBS was associated with smaller perturbation effects (p ≤ 0.011). A negative correlation was found between the perturbation effect and the tracking error, in the higher EBS-group (r = -0.5, p = 0.013).

INTERPRETATION

These results demonstrate that pain-related cognitions influence trunk movement control and support the idea that more negative pain-related cognitions lead to an increased resistance against perturbations, at the expense of movement precision.

Effects of sling exercises on pain, function, and corticomuscular functional connectivity in individuals with chronic low back pain- preliminary study

BACKGROUND

Individuals with chronic low back pain (CLBP) exhibit altered brain function and trunk muscle activation.

AIM

This study examined the effects of sling exercises on pain, function, and corticomuscular coherence (CMC) in healthy adults and individuals with CLBP.

METHODS

Eight individuals with CLBP and 15 healthy adults received sling exercise training for 6 weeks. Before and after training, participants performed two motor tasks: rapid arm lifts and repeated trunk flexion-extension tasks, and electromyography of the trunk muscles and electroencephalography of the sensorimotor cortex were recorded. Chi-squared test and Mann-Whitney U tests were used for between group comparison, and Wilcoxon signed-rank tests were used for pre- and post-training comparison. Spearman's Rank Correlation Coefficient (Rs) was used to identify for the relationship between motor performance and Corticomuscular coherence.

RESULTS

Sling exercises significantly improved pain (median from 3 to 1, p = .01) and Oswestry Disability Index scores (median from 2.5 to 2, p = .03) in the CLBP group. During rapid arm lifts, individuals with CLBP showed lower beta CMC of the transverse abdominis and internal oblique (Tra/IO) (0.8 vs. 0.49, p = .01) and lumbar erector spinae (0.70 vs. 0.38, p = .04) than the control group at baseline. During trunk flexion-extension, the CLBP group showed higher gamma CMC of the left Tra/IO than the control group at baseline (0.28 vs. 0.16 , p = .001). After training, all CMC became statistically non-significant between groups. The training induced improvement in anticipatory activation of the Tra/IO was positively correlated with the beta CMC (rs = 0.7851, p = .02).

CONCLUSION

A 6-week sling exercises diminished pain and disability in patients with CLBP and improved the anticipatory activation and CMC in some trunk muscles. These improvements were associated with training induced changes in corticomuscular connectivity in individuals with CLBP.

Thermoreversible Reverse-Phase-Shift Foam for Treatment of Noncompressible Torso Hemorrhage, a Safety Trial in a Porcine Model

INTRODUCTION

Noncompressible torso hemorrhage is the leading cause of exsanguination on the battlefield. A self-expanding, intraperitoneal deployed, thermoreversible foam has been developed that can be easily administered by a medic in austere settings to temporarily tamponade noncompressible torso hemorrhage. The purpose of this study was to assess the long-term safety and physical characteristics of using Fast Onset Abdominal Management (FOAM; Critical Innovations LLC) in swine.

MATERIALS AND METHODS

Yorkshire swine (40-60 kg) were sedated, intubated, and placed on ventilatory support. An external jugular catheter was placed for sampling of blood. Continuous heart rate, temperature, saturation of peripheral oxygen, end-tidal carbon dioxide, and peak airway pressures were monitored for a 4-hour period after intervention (i.e., FOAM agent injection or a sham introducer without agent delivery). The FOAM agent was injected to obtain an intra-abdominal pressure of 60 mmHg for at least 10 minutes. After 4 hours, the animals were removed from ventilatory support and returned to their housing for a period of 7-14 days. Group size analysis was not performed, as this was a descriptive safety study. Blood samples were obtained at baseline and at 1-hour post-intervention and then on days 1, 3, 7, and 14. Euthanasia, necropsy, and harvesting of samples for histologic analysis (from kidneys, terminal ilium, liver, pancreas, stomach, spleen, and lungs) were performed upon expiration. Histologic scoring for evidence of ischemia, necrosis, and abdominal compartment sequela was blinded and reported by semi-quantitative scale (range 0-4; 0 = no change, 1 = minimal, 2 = mild, 3 = moderate, and 4 = marked). Oregon Health & Science University's Institutional Animal Care and Use Committee, as well as the U.S. Army Animal Care and Use Review Office, approved this protocol before the initiation of experiments (respectively, protocol numbers IP00003591 and MT180006.e002).

RESULTS

Five animals met a priori inclusion criteria, and all of these survived to their scheduled endpoints. Two animals received sham injections of the FOAM agent (one euthanized on day 7 and one on day 14), and three animals received FOAM agent injections (one euthanized on day 7 and two on day 14). A transitory increase in creatinine and lactate was detected during the first day in the FOAM injected swine but resolved by day 3. No FOAM agent was observed in the peritoneal cavity upon necropsy at day 7 or 14. Histologic data revealed no clinically relevant differences in any organ system between intervention and control animals upon sacrifice at day 7 or 14.

CONCLUSIONS

This study describes the characteristics, survival, and histological analysis of using FOAM in a porcine model. In our study, FOAM reached the desired intra-abdominal pressure endpoint while not significantly altering basic hematologic parameters, except for transient elevations of creatinine and lactate on day 1. Furthermore, there was no clinical or histological relevant evidence of ischemia, necrosis, or intra-abdominal compartment syndrome. These results provide strong support for the safety of the FOAM device and will support the design of further regulatory studies in swine and humans.

The Effect of a Novel Weight-Supported Kinetic Chain Resistance Training Program on Proximal Core Muscular Endurance, Trunk-to-Arm Muscular Power, and Bat Swing Speed

ABSTRACT

Palmer, TG, and McCabe, M. The effect of a novel weight-supported kinetic chain resistance training program on proximal core muscular endurance, trunk-to-arm muscular power, and bat swing speed. J Strength Cond Res 37(11): 2130-2140, 2023-Muscular stability and muscular power at the proximal core segments of the pelvis, spine, and trunk are essential attributes in maximizing bat swing speed in the sport of softball. Weight-supported kinetic chain resistance training (WsKC) is a novel closed kinetic chain technique that provides synergistic multiplanar stressors to the proximal core segments via the lower and upper extremities while limiting joint compression and sheer forces throughout the kinetic chain. The aim of this study was to assess the effect a 7-week preseason WsKC program would have on an isometric muscular endurance plank, trunk-to-arm peak muscular power (TAPP), trunk-to-arm peak velocity (TAPV), and bat swing speed (BSS) compared with a traditional isotonic weight resistance training program. Twenty-seven female high school softball players (age = 16 years, height = 167.6 cm, body mass = 62.86 kg) were assigned in a blocked randomization to one of 2 groups: a standing weight-supported kinetic chain resistance training (WsT) group (n = 13) or a pseudo-control traditional isotonic training (TT) group (n = 14). The WsT group had significant improvements (p < 0.05) for the isometric endurance plank (p = 0.001), TAPP (p = 0.002), TAPV (p = 0.001), and BSS (p = 0.02) compared with the TT group. The training effect size (ES) was large for the WsT group for all variables (ES = 1.0-7.4) and small to moderate for a majority of the TT variables (ES = 0.06-0.47). The simultaneous improvement in the isometric endurance plank, trunk-to-arm rotations, and BSS indicates that the WsKC contributed to subsequent improvements in BSS in high school softball players.

Comparison of child and ATD belt fit and posture on belt-positioning boosters during self-selected, holding device, and nominal conditions

OBJECTIVE

Pediatric anthropomorphic test devices (ATDs) are important tools for the assessment of child occupant protection and should represent realistic child belt fit and posture on belt-positioning boosters. Previous comparisons have been made to children in either self-selected or nominal postural conditions. This study compares belt fit and postural measurements between pediatric ATDs and a single cohort of children assuming different postures on boosters: self-selected, holding a portable electronic device, and nominal.

METHODS

A cohort of children (n = 25) were evaluated in a stationary vehicle on five boosters and in three postural conditions: nominal, self-selected, and a representative holding electronic device position. The Hybrid III 6- and 10-year-old and Q-Series 6- and 10-year-old ATDs were evaluated in the same five boosters and in two postural conditions: nominal and a representative holding electronic device position. A 3D coordinate measurement device was used to quantify belt fit (shoulder belt score, lap belt score, maximum gap size, and gap length) and anatomic landmark positions (head, suprasternale, ASIS, and patella). Landmark positions and belt fit were compared between ATDs and children for each booster and postural condition, and Pearson correlations (r) were assessed across boosters.

RESULTS

ATDs generally represented Nominal child postures across boosters. In the Device condition, ATDs were seldom able to be positioned to represent both the torso and head position of children, due to limited ATD spinal flexibility. When the torso position was matched, the ATD head was more rear by 63 mm. Correlations between Nominal child and ATD belt fit and belt gap metrics were generally weak and not significant, with the exception of lap belt score (all ATDs p < 0.07, r = 0.8549-0.9857).

DISCUSSION

ATDs were generally able to represent realistic child postures and lap belt fit in Nominal and short duration Self-selected postures in a laboratory setting. However, these results display the potential difficulty of utilizing ATDs to represent more naturalistic child postures, especially the more forward head positions and flexed spinal posture associated with utilizing a portable electronic device.

Robotic upright stand trainer (RobUST) and postural control in individuals with spinal cord injury

CONTEXT/OBJECTIVE

Assessed feasibility and potential effectiveness of using a novel robotic upright stand trainer (RobUST) to deliver postural perturbations or provide assistance-as-needed at the trunk while individuals with spinal cord injury (SCI) performed stable standing and self-initiated trunk movements. These tasks were assessed with research participants' hands on handlebars for self-balance assistance (hands on) and with hands off (free hands).

DESIGN

Proof of concept study.

PARTICIPANTS

Four individuals with motor complete (n = 3) or incomplete (n = 1) SCI who were not able to achieve independent standing and presented a neurological lesion level ranging from cervical 4 to thoracic 2.

OUTCOME MEASURES

Ground reaction forces, trunk displacement, and electromyography activity of trunk and lower limb muscles.

RESULTS

Research participants received continuous pelvic assistance via RobUST, and manual trainer assistance at the knees to maintain standing. Participants were able to attempt all tasks. Free hands trunk perturbations resulted in greater load bearing-related sensory information (73% ipsilateral vertical loading), trunk displacement (57%), and muscle activation compared to hands on. Similarly, free hands stable standing with RobUST assistance-as-needed resulted in 8.5% larger bodyweight bearing, 112% larger trunk movement velocity, and higher trunk muscles activation compared to standing with hands on. Self-initiated trunk movements controlled by hands on showed 116% greater trunk displacement, 10% greater vertical ground reaction force, and greater ankle muscle activation compared to free hands.

CONCLUSION

RobUST established a safe and challenging standing environment for individuals with SCI and has the potential to improve training paradigms and assessments of standing postural control.

Validation of Inertial Measurement Units for Analyzing Golf Swing Rotational Biomechanics

Training devices to enhance golf swing technique are increasingly in demand. Golf swing biomechanics are typically assessed in a laboratory setting and not readily accessible. Inertial measurement units (IMUs) offer improved access as they are wearable, cost-effective, and user-friendly. This study investigates the accuracy of IMU-based golf swing kinematics of upper torso and pelvic rotation compared to lab-based 3D motion capture. Thirty-six male and female professional and amateur golfers participated in the study, nine in each sub-group. Golf swing rotational kinematics, including upper torso and pelvic rotation, pelvic rotational velocity, S-factor (shoulder obliquity), O-factor (pelvic obliquity), and X-factor were compared. Strong positive correlations between IMU and 3D motion capture were found for all parameters; Intraclass Correlations ranged from 0.91 (95% confidence interval [CI]: 0.89, 0.93) for O-factor to 1.00 (95% CI: 1.00, 1.00) for upper torso rotation; Pearson coefficients ranged from 0.92 (95% CI: 0.92, 0.93) for O-factor to 1.00 (95% CI: 1.00, 1.00) for upper torso rotation (p < 0.001 for all). Bland-Altman analysis demonstrated good agreement between the two methods; absolute mean differences ranged from 0.61 to 1.67 degrees. Results suggest that IMUs provide a practical and viable alternative for golf swing analysis, offering golfers accessible and wearable biomechanical feedback to enhance performance. Furthermore, integrating IMUs into golf coaching can advance swing analysis and personalized training protocols. In conclusion, IMUs show significant promise as cost-effective and practical devices for golf swing analysis, benefiting golfers across all skill levels and providing benchmarks for training.

Experimental protocol to investigate cortical, muscular and body representation alterations in adolescents with idiopathic scoliosis

BACKGROUND

Adolescent idiopathic scoliosis (AIS) is the most common form of scoliosis. AIS is a three-dimensional morphological spinal deformity that affects approximately 1-3% of adolescents. Not all factors related to the etiology of AIS have yet been identified.

OBJECTIVE

The primary aim of this experimental protocol is to quantitatively investigate alterations in body representation in AIS, and to quantitatively and objectively track the changes in body sensorimotor representation due to treatment.

METHODS

Adolescent girls with a confirmed diagnosis of mild (Cobb angle: 10°-20°) or moderate (21°-35°) scoliosis as well as age and sex-matched controls will be recruited. Participants will be asked to perform a 6-min upright standing and two tasks-named target reaching and forearm bisection task. Eventually, subjects will fill in a self-report questionnaire and a computer-based test to assess body image. This evaluation will be repeated after 6 and 12 months of treatment (i.e., partial or full-time brace and physiotherapy corrective postural exercises).

RESULTS

We expect that theta brain rhythm in the central brain areas, alpha brain rhythm lateralization and body representation will change over time depending on treatment and scoliosis progression as a compensatory strategy to overcome a sensorimotor dysfunction. We also expect asymmetric activation of the trunk muscle during reaching tasks and decreased postural stability in AIS.

CONCLUSIONS

Quantitatively assess the body representation at different time points during AIS treatment may provide new insights on the pathophysiology and etiology of scoliosis.

Patient Pre-operative Planning of Gluteal Augmentation

Demand for autologous gluteal augmentation with fat transfer continues to rise paralleling the increasingly complex nature of the operation. Improved overall aesthetic outcomes are a result of: (1) donor site fat harvest has evolved to circumferential torso high-definition lipo-sculpting; (2) a shift from indiscriminate buttock augmentation to precise gluteal re-shaping. Discussing complex operations with patients, particularly ones of artistic nature, can be challenging. The senior author has developed a gluteal re-shaping graphic to focus a patient's attention to the four most important areas. It also serves as a foundation for surgeons to create operative plans and track outcomes for professional development.

Physics-Guided Deep Scatter Estimation by Weak Supervision for Quantitative SPECT

Accurate scatter estimation is important in quantitative SPECT for improving image contrast and accuracy. With a large number of photon histories, Monte-Carlo (MC) simulation can yield accurate scatter estimation, but is computationally expensive. Recent deep learning-based approaches can yield accurate scatter estimates quickly, yet full MC simulation is still required to generate scatter estimates as ground truth labels for all training data. Here we propose a physics-guided weakly supervised training framework for fast and accurate scatter estimation in quantitative SPECT by using a 100× shorter MC simulation as weak labels and enhancing them with deep neural networks. Our weakly supervised approach also allows quick fine-tuning of the trained network to any new test data for further improved performance with an additional short MC simulation (weak label) for patient-specific scatter modelling. Our method was trained with 18 XCAT phantoms with diverse anatomies / activities and then was evaluated on 6 XCAT phantoms, 4 realistic virtual patient phantoms, 1 torso phantom and 3 clinical scans from 2 patients for 177Lu SPECT with single / dual photopeaks (113, 208 keV). Our proposed weakly supervised method yielded comparable performance to the supervised counterpart in phantom experiments, but with significantly reduced computation in labeling. Our proposed method with patient-specific fine-tuning achieved more accurate scatter estimates than the supervised method in clinical scans. Our method with physics-guided weak supervision enables accurate deep scatter estimation in quantitative SPECT, while requiring much lower computation in labeling, enabling patient-specific fine-tuning capability in testing.

Application of wireless energy transmission technology into central venous ports with light-emitting diodes

Implantable central venous (CV) ports are widely used for chemotherapy and parenteral nutrition. Generally, CV ports are used safely; however, some patients suffer from drug leakage around the port septum due to mispuncture. Therefore, we developed a CV port that is visible under the skin. We created a prototype of a CV port using a 3D printer. Three red light-emitting diodes (LEDs) were attached around the septum that made the puncture site visible by applying wireless energy transmission technology using electromagnetic resonance. The CV port was implanted under the skin of pork rose meat. The thickness of the skin of pork loin was measured. Fifteen medical doctors participated in the study to visually confirm the lighted CV port. The visibility of the center of the septum with and without lights was scored 0 as non-diagnostic; 1, slightly visible; 2, well visible; and 3, obviously visible. The visibility with or without lights was assessed. The relationship between the years of experience and the visibility score was assessed. The Wilcoxon test was used for statistical analysis. LEDs were easily transmitted through the skin of pork rose meat. The median visibility scores with or without lights were 2 (range, 1-3) and 3 (range, 1-3), respectively (p = 0.005). No significant relationship was found between experience and visibility score (p = 0.289). CV ports with LEDs can be easily recognized compared with those without LEDs. This technique may contribute to medical safety by improving its visibility to avoid mispuncture.

Vertical contact forces affect vibration perception in human hairy skin

Background

Skin is the largest organ of the human body and fulfills many important functions, like detecting mechanical stimuli. Skin can be divided into glabrous (non-hairy) and hairy skin. These two skin types differ with regard to their mechanical properties and in the distribution of mechanoreceptors. Although many investigations focus on glabrous skin, hairy skin still plays a fundamental role in various activities, e.g., with regard to the perception of pleasantness or for developing wearable vibrotactile devices for pattern recognition in persons with disabilities. Unfortunately, investigations on influencing factors, like vertical contactor force, are scarce for hairy skin. Similarly, it would also be interesting to investigate whether regional vibratory sensitivity differences are present across the human torso. Hence, this study investigated the effects of vertical contactor forces and different anatomical locations on vibration perception. Four anatomical torso regions were studied. Based on findings in glabrous skin, we generally hypothesized improved vibration perception with increasing contactor forces and regional sensitivity differences between the anatomical locations.

Methods

Forty young and healthy individuals participated (23.0 ± 2.0 yrs), and vibration perception thresholds (VPTs) were determined at 30 Hz for three vertical force levels (0.6, 2.4, and 4.8 N) at four torso locations (sternum, deltoid/shoulder, lower back, middle lateral torso side).

Results

Higher contactor forces resulted in lower VPTs corresponding to improved vibration perception, regardless of anatomical location. In addition, the sternum region was more sensitive than the remaining three regions, regardless of force level. The reasons for these findings may be a varying number and activation pattern of afferents activated under the different conditions. The findings of this study complement the understanding of vibrotactile sensitivity in hairy skin and may offer implications when developing vibrotactile devices or clothing/textiles, for example.

Diagnosis of thoracic outlet syndrome with the lower trunk compression of brachial plexus by high-frequency ultrasonography

BACKGROUND

Thoracic outlet syndrome (TOS) with the lower trunk compression of brachial plexus (BP) is difficult to diagnosis. This study aimed to summarize the features of thoracic outlet syndrome (TOS) with the lower trunk compression of brachial plexus observed on high-frequency ultrasonography (HFUS).

METHODS

The ultrasound data of 27 patients who had TOS with the lower trunk compression of brachial plexus were collected and eventually confirmed by surgery. The imaging data were compared, and the pathogenesis of TOS was analyzed on the basis of surgical data.

RESULTS

TOS occurred predominantly in females (70.4%). Most cases had unilateral involvement (92.6%), mainly on the right side (66.7%). The HFUS features of TOS can be summarized as follows: (1) Lower trunk compression. HFUS revealed focal thinning that reflected compression at the level of the lower trunk; furthermore, the distal part of the nerve was thickened for edema (Affected side: 0.49 ± 0.12 cm vs. Healthy side: 0.38 ± 0.06, P = 0.009), and the cross-sectional area of brachial plexus cords was markedly greater on the injured side than on the healthy side (0.95 ± 0.08 cm² vs. 0.65 ± 0.11 cm², P = 0.004). (2) Hyperechoic fibromuscular bands behind the compressed nerve (mostly the scalenus minimus muscle). (3) Abnormal bony structures: cervical ribs or elongated transverse processes of the 7th cervical vertebra (C7). Surgical results showed that the etiological factors contributing to TOS were (1) muscle hypertrophy and/or fibrosis (100%) and (2) cervical ribs/elongated C7 transverse processes (20.7%).

CONCLUSION

TOS with the lower trunk compression of brachial plexus can be diagnosed accurately and reliably by high-frequency ultrasound.

Full Torso Coverage Armor for Females

INTRODUCTION

Body armor and torso-borne equipment are critical to the survivability and operational effectiveness of a soldier. Historically, in-service designs have been predominantly designed for males or unisex, which may be disadvantageous for females who are shaped differently and, on average, smaller in stature and mass than their male counterparts. This study assesses the biomechanical and performance impact of two Canadian in-service armors and fighting load conditions on females.

MATERIALS AND METHODS

Four tasks (i.e., range of motion, treadmill march [×2], and a wall obstacle) were performed in a Baseline condition and two in-service torso-borne equipment conditions; the full torso coverage (FTC) condition has full upper torso soft armor with the fighting load carried in a separate vest, while the reduced coverage (RC) has a plate carrier with fighting load integrated into the armor carrier, bulk positioned higher, and less torso coverage. Both used identical combat loads and front and back armor plates. Trunk range of motion, march lower limb kinematics, march shoulder and hip skin pressures, perceived discomfort after the march, and time to traverse a wall obstacle were captured. Data were collected to assess the biomechanics and usability of the systems for eight females, representative of military recruits. Linear mixed-effects models were created, and analysis of variances (ANOVAs) were then performed on all the outcome measures (P < .05). Tukey's post-hoc procedures were performed when appropriate (P < .05).

RESULTS

There were significant differences between the RC and FTC for the sit and reach test (P < .001), lateral bend test (P < .001), and wall traverse time (P < .01). In all cases, the RC outperformed FTC. There were no differences between the two in-service conditions with respect to hip, knee, and ankle flexion/extension. The RC average skin pressure was higher than the FTC at the left and right shoulders by 103% and 79%, respectively, and peak skin pressure at the left shoulder by 75%. Both in-service conditions showed decrements in performance from Baseline for sit and reach (P < .001), lateral bend (P < .001), and peak hip and knee flexion (P < .01) with the FTC showing decreases in trunk rotation (P < .001) and wall traverse time (P < .01).

CONCLUSIONS

Improved outcomes for the RC can be attributed to design differences. The lower placement of bulk in FTC may act as a physical barrier during range of motion tasks and the wall obstacle. The presence of shoulder caps on FTC provides another physical barrier that likely impedes full movement through the arms and shoulders. While the narrower shoulder straps of the RC remove the barrier, it causes more concentrated skin pressures on the shoulder that can lead to injury. The results suggest that the RC offers a potential for increased operational effectiveness in females (and potentially for males) compared to the FTC system. Shoulder pressure, an important predictor of discomfort and injury, is the only measure for which FTC outperformed the RC. Future torso-borne equipment designs targeting this outcome measure could help increase the effectiveness of the RC and other similar systems that reduce torso coverage, though survivability implications must also be considered.

Evaluating the Efficacy of a New Alternating Pressure Air Mattress Aimed at Reducing Pressure Injuries During the Transport of Combat Casualties

INTRODUCTION

The development of pressure ulcers during aeromedical transport of combat casualties is an issue that continues to exist, especially during long transport flights. This study investigated the potential for a new intervention, an air-inflated insulating mattress pad (IMP) that has a pump system designed to alternate the pressurization of air cells under the patient, thus temporally shifting the pressure concentration locations.

MATERIALS AND METHODS

In a repeated measures design study, 12 participants experienced the following four simulated transport conditions, each for 90 minutes: (1) The North Atlantic Treaty Organization (NATO) litter by itself (control condition), (2) the NATO litter covered with the standard mattress pad (Warrior Evacuation Pad), (3) the NATO litter covered with the air-inflated mattress (IMP), and (4) the NATO litter, covered with the standard mattress pad that was covered by the insulating mattress pad. Peak pressure readings were obtained every 15 seconds under the head, torso, pelvis, legs, and heels.

RESULTS

While both mattress pads significantly reduced the peak pressures relative to the litter-only condition, the new IMP with the alternating cell pressurizations, by itself or in combination with the standard mattress pad, further reduced the peak pressures under the regions with the localized highest pressures, namely the head, pelvis, and heels. Moreover, the IMP with alternating pressure introduced the most variability in the peak pressure readings, which reduces the peak pressure exposure periods for specific tissue locations.

CONCLUSIONS

The IMP with alternating cell pressurizations could further reduce the likelihood of pressure injuries during aeromedical transport of combat casualties.

Common complications and prevention strategies for resuscitative endovascular balloon occlusion of the aorta: A narrative review

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is considered a key measure of treatment due to its use in stabilizing patients in shock through temporary inflow occlusion for noncompressible torso hemorrhage as well as its supportive role in myocardial and cerebral perfusion. Although its clinical efficacy in trauma has been widely recognized, concerns over related complications, such as vascular access and ischemia-reperfusion, are on the rise. This paper aims to investigate complications associated with REBOA and identify current and emerging prevention or mitigation strategies through a literature review based on human or animal data. Common complications associated with REBOA include ischemia/reperfusion injuries, vessel injuries, venous thromboembolism, and worsening proximal bleeding. REBOA treatment outcomes can be improved substantially with the help of precise selection of patients, better visualization tools, improvement in balloon catheters, blockage strategies, and medication intervention measures. Better understanding of REBOA-related complications and further research on the strategies to mitigate the occurrence of such complications will be of vital importance for the optimization of the clinical outcomes in patients.

Dependence of trunk muscle size and position on age, height, and weight in a multi-ethnic cohort of middle-aged and older men and women

Trunk muscle size and location relative to the spine are key factors affecting their capacity to assist in trunk movement, strength, and function. There remains limited information on how age, weight and height affect these measurements across multiple spinal levels, and prior studies had limited samples in terms of size and ethnicity. In this study, we measured trunk muscles in coronal plane slices at T4 - L4 of CT scans acquired in 507 participants, aged 40-90 years, from the community-based Framingham Heart Study. Mixed-effects linear regressions, stratified by sex, determined the contributions of age, height and weight, to muscle cross-sectional area (CSA), the distance from the vertebral body centroid (CD), and the in-plane angle of the line between the vertebral body and the muscle centroids (CA). Muscle CSA decreased with higher age by an average of -0.8% per year, but weight (average 0.8% per kg) and height (average -0.05% per cm) had mixed results, with both positive and negative effects depending on muscle group and level. Muscle CD increased with weight by an average of 0.3% per kg, but had mixed effects for age (average 0.8% per year) and height (average 0.1% per cm). Muscle CA had mixed associations with age (average 0.05% per year), weight (average 0.01% per kg) and height (average -0.05% per cm). A prediction program created with these results provides a simple approach for estimating probable values for trunk muscle size and position in the absence of medical imaging.

Variations in Concurrent Validity of Two Independent Inertial Measurement Units Compared to Gold Standard for Upper Body Posture during Computerised Device Use

Inertial measurement units (IMUs) may provide an objective method for measuring posture during computer use, but research is needed to validate IMUs' accuracy. We examine the concurrent validity of two different IMU systems in measuring three-dimensional (3D) upper body posture relative to a motion capture system (Mocap) as a potential device to assess postures outside a laboratory environment. We used 3D Mocap and two IMU systems (Wi-Fi and Bluetooth) to capture the upper body posture of twenty-six individuals during three physical computer working conditions (monitor correct, monitor raised, and laptop). Coefficient of determination (R2) and root-mean-square error (RMSE) compared IMUs to Mocap. Head/neck segment [HN], upper trunk segment [UTS], and joint angle [HN-UTS] were the primary variables. Wi-Fi IMUs demonstrated high validity for HN and UTS (sagittal plane) and HN-UTS (frontal plane) for all conditions, and for HN rotation movements (both for the monitor correct and monitor raised conditions), others moderate to poor. Bluetooth IMUs for HN, and UTS (sagittal plane) for the monitor correct, laptop, and monitor raised conditions were moderate. Frontal plane movements except UTS (monitor correct and laptop) and all rotation had poor validity. Both IMU systems were affected by gyroscopic drift with sporadic data loss in Bluetooth IMUs. Wi-Fi IMUs had more acceptable accuracy when measuring upper body posture during computer use compared to Mocap, except for trunk rotations. Variation in IMU systems' performance suggests validation in the task-specific movement(s) is essential.

KLK11 ichthyosis: large truncal hyperkeratotic pigmented plaques underscore a distinct autosomal dominant disorder of cornification

Recently, Gong et al. reported two substitutions, p.(Gly50Glu) and p.(Gly50Arg), located at the last amino acid of the estimated signal peptide in kallikrein11 (KLK11) in three independent ichthyosiform erythroderma or erythrokeratoderma pedigrees (Gong et al., Br J Dermatol, 2023). Here, we present a further case of autosomal dominant congenital ichthyosiform erythroderma caused by the p.(Gly50Glu) substitution in KLK11; the patient had sharply demarcated pigmented hyperkeratotic lesions. Thus, p.(Gly50Glu) in KLK11 might represent a recurrent variant underlying this recently reported autosomal dominant disorder of cornification, and the large hyperkeratotic pigmented plaques seen in all patients may represent a pathognomonic part of the phenotype.