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Accurate representation of spinal geometry is necessary in biomechanical modelling to properly understand the function of the spine. The objective of this study was to create a large database of image-derived digital spine surface models for geometric studies and computational biomechanics investigation. Computed tomography scan data was acquired from 60 asymptomatic subjects (30 males and 30 females). Subjects ranged in age from 20 to 68 with equal numbers selected in each 10-year age bracket. Three-dimensional geometric surface models were generated for each subject's spine. A series of distance measures were also computed for each vertebral body to assess variation in the population. Geometric measures were able to show the significant variation in vertebrae size and shape within the subject population and as a function of vertebral level, gender, and age. This database enables the biomechanical evaluation of the variation in spinal loads that occurs within the population due to geometry. [ABSTRACT FROM AUTHOR]

This study focuses on what aspects of attributes of spirituality as defined by Martsolf and Mickley (1998) are most salient for female and male survivors of sexual violence. Content analysis of secondary narrative data, provided by 50 participants in a study of women's and men's responses to sexual violence, was coded to the five attributes of spirituality as defined by Martsolf and Mickley. The attribute aspects of connecting with others in spiritual ways and with God/higher power were particularly significant. The attribute of transcendence was found less important, and the attributes of value, becoming, and meaning were not found important. The Martsolf and Mickley framework helped organize narrative data for a content analysis of spirituality in survivors of sexual violence.

Introduction Low back pain is a significant burden to society and the lack of reliable outcome measures, combined with a prevailing inability to quantify the biopsychosocial elements implicated in the disease, impedes clinical decision- making and distorts treatment efficacy. This paper aims to validate the utility of a biopsychosocial spine platform to provide standardized wearable sensor- derived functional motion assessments to assess spine function and differentiate between healthy controls and patients. Secondarily, we explored the correlation between these motion features and subjective biopsychosocial measures. Methods An observational study was conducted on healthy controls (n=50) and patients with low back pain (n=50) to validate platform utility. The platform was used to conduct functional assessments along with patient- reported outcome assessments to holistically document cohort differences. Our primary outcomes were motion features; and our secondary outcomes were biopsychosocial measures (pain, function, etc). Results Our results demonstrated statistically significant differences in motion features between healthy and patient cohorts across anatomical planes. Importantly, we found velocity and acceleration in the axial plane showed the largest difference, with healthy controls having 49.7% and 55.7% higher values, respectively, than patients. In addition, we found significant correlations between motion features and biopsychosocial measures for pain, physical function and social role only. Conclusions Our study validated the use of wearable sensor- derived functional motion metrics in differentiating healthy controls and patients. Collectively, this technology has the potential to facilitate holistic biopsychosocial evaluations to enhance spine care and improve patient outcomes. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate three passive upper-extremity exoskeletons relative to a control condition. Twelve subjects performed an hour-long, simulated occupational task in a laboratory setting. Independent measures of exoskeleton, exertion height (overhead, head height), time, and their interactions were assessed. Dependent measures included changes in tissue oxygenation (ΔTSI) in the anterior deltoid and middle trapezius, peak resultant lumbar spine loading, and subjective discomfort in various body regions. A statistically significant reduction in ΔTSI between exoskeleton and control was only observed in one instance. Additionally, neither increases in spinal loading nor increases in subjective discomfort ratings were observed for any of the exoskeletons. Ultimately, the exoskeletons offered little to no physiological benefit for the conditions tested. However, the experimental task was not highly fatiguing to the subjects, denoted by low ΔTSI values across conditions. Results may vary for tasks requiring constant arm elevation or higher force demands. Practitioner summary This study quantified the benefits of upper-extremity exoskeletons using NIRS, complementary to prior studies using EMG. The exoskeletons offered little to no physiological benefit for the conditions tested. However, the experimental task was not highly fatiguing, and results may vary for an experimental task with greater demand on the shoulders. Abbreviations: WMSD: work-related musculoskeletal disorder; EMG: electromyography; NIRS: near-infrared spectroscopy; NIR: near-infrared; Hb: haemoglobin; Mb: myoglobin; TSI: tissue saturation index; ATT: adipose tissue thickness [ABSTRACT FROM AUTHOR]

Purpose: To compare the accuracy of implant master casts fabricated using Robocast Technology (Biomet 3i) with that of master casts fabricated using traditional transfer (closed-tray) and pick-up (open-tray) techniques. Materials and Methods: A stereolithographic replica of a Kennedy Class I human mandible was fabricated for use as the master model. Implants were placed into both posterior quadrants (both second premolars and second molars) and set parallel (P) on one side and divergent (nonparallel, NP) on the opposite side. Impressions were made of the master model (patient replica model) with Encode Healing Abutments, open-tray, and closed-tray impression copings. Identical metallic spheres were placed onto each implant analog in the stone master casts, and the casts/spheres were scanned using a digital scanner. Measurements were made between the center points of the spheres and compared to the master model. Data were divided into P, NP, and individual sites, and the differences were analyzed statistically (α = .05). Results: Encode master casts were less accurate than the open-tray casts in NP sites. Encode master casts were less accurate than the open-tray and closed-tray casts in P sites. NP sites demonstrated less accuracy than P sites within the Encode group. Encode master casts were less accurate than the open- and closed-tray casts at the mandibular right second premolar site. The mandibular left second premolar was less accurate than the mandibular right second molar in the Encode group. Conclusions: Within the limitations of this lab-based study and analysis, the Encode technique resulted in master casts that were less accurate than master casts made from traditional open- and closed-tray impression techniques. Further research is necessary before specific clinical judgments can be made. [ABSTRACT FROM AUTHOR]

Though biomechanically determined guidelines exist for lifting, existing recommendations for pushing and pulling were developed using a psychophysical approach. The current study aimed to establish objective hand force limits based on the results of a biomechanical assessment of the forces on the lumbar spine during occupational pushing and pulling activities. Sixty-two subjects performed pushing and pulling tasks in a laboratory setting. An electromyography-assisted biomechanical model estimated spinal loads, while hand force and turning torque were measured via hand transducers. Mixed modelling techniques correlated spinal load with hand force or torque throughout a wide range of exposures in order to develop biomechanically determined hand force and torque limits. Exertion type, exertion direction, handle height and their interactions significantly influenced dependent measures of spinal load, hand force and turning torque. The biomechanically determined guidelines presented herein are up to 30% lower than comparable psychophysically derived limits and particularly more protective for straight pushing. Practitioner Summary: This study utilises a biomechanical model to develop objective biomechanically determined push/pull risk limits assessed via hand forces and turning torque. These limits can be up to 30% lower than existing psychophysically determined pushing and pulling recommendations. Practitioners should consider implementing these guidelines in both risk assessment and workplace design moving forward. [ABSTRACT FROM AUTHOR]

Early biomechanical spine models represented the trunk muscles as straight-line approximations. Later models have endeavoured to accurately represent muscle curvature around the torso. However, only a few studies have systematically examined various techniques and the logic underlying curved muscle models. The objective of this review was to systematically categorise curved muscle representation techniques and compare the underlying logic in biomechanical models of the spine. Thirty-five studies met our selection criteria. The most common technique of curved muscle path was the ‘via-point’ method. Curved muscle geometry was commonly developed from MRI/CT database and cadaveric dissections, and optimisation/inverse dynamics models were typically used to estimate muscle forces. Several models have attempted to validate their results by comparing their approach with previous studies, but it could not validate of specific tasks. For future needs, personalised muscle geometry, and person- or task-specific validation of curved muscle models would be necessary to improve model fidelity. Practitioner Summary: The logic underlying the curved muscle representations in spine models is still poorly understood. This literature review systematically categorised different approaches and evaluated their underlying logic. The findings could direct future development of curved muscle models to have a better understanding of the biomechanical causal pathways of spine disorders. [ABSTRACT FROM AUTHOR]