14,961 research outputs found

    Osteoarthritis, entheses, and long bone cross-sectional geometry in the Andes: Usage, history, and future directions.

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    Akin to approaches encouraged by Verano (1997) in the Andes, and Ortner (2011, 2012) for general paleopathological studies, this article focuses on accurate descriptions and definitions of osteoarthritis, entheses, and long bone cross-sectional geometry. By evaluating these conditions as part of biological responses to abnormal skeletal changes and biomechanical stress, this research discusses each condition's pathogenesis. Further, this article emphasizes a "small data" approach to evaluating these conditions in ancient culturally and biologically related human populations, where the study samples must have good skeletal preservation, where estimates of age and sex need to be included as major factors, and where abnormalities need to be described and evaluated. This article also discusses global clinical and osteological research on ways scholars are currently trying to establish industry-wide methods to evaluate osteoarthritis, entheses, and long bone cross-sectional geometry. Recent studies have focused on rigorous evaluation of methodological techniques, recording protocols, and inter- and intra-observer error problems. Additionally, scholars have focused on physical intensity of movement using biomechanics, evaluated burials of known occupation, and used complex statistical methods to help interpret skeletal changes associated with these conditions. This article also narrows to focus on these conditions within thematic "small data" areas throughout the Andes. This research concludes with describing future directions to understand skeletal changes, such as more multidisciplinary studies between osteologists and pathologists, collaborations with living people to collect CT, x-rays, or computer-aided motion capture, and a stronger focus on how these conditions correlate with intense biomechanical changes in younger individuals

    Improving activity recognition using a wearable barometric pressure sensor in mobility-impaired stroke patients.

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    © 2015 Massé et al.Background: Stroke survivors often suffer from mobility deficits. Current clinical evaluation methods, including questionnaires and motor function tests, cannot provide an objective measure of the patients mobility in daily life. Physical activity performance in daily-life can be assessed using unobtrusive monitoring, for example with a single sensor module fixed on the trunk. Existing approaches based on inertial sensors have limited performance, particularly in detecting transitions between different activities and postures, due to the inherent inter-patient variability of kinematic patterns. To overcome these limitations, one possibility is to use additional information from a barometric pressure (BP) sensor. Methods: Our study aims at integrating BP and inertial sensor data into an activity classifier in order to improve the activity (sitting, standing, walking, lying) recognition and the corresponding body elevation (during climbing stairs or when taking an elevator). Taking into account the trunk elevation changes during postural transitions (sit-to-stand, stand-to-sit), we devised an event-driven activity classifier based on fuzzy-logic. Data were acquired from 12 stroke patients with impaired mobility, using a trunk-worn inertial and BP sensor. Events, including walking and lying periods and potential postural transitions, were first extracted. These events were then fed into a double-stage hierarchical Fuzzy Inference System (H-FIS). The first stage processed the events to infer activities and the second stage improved activity recognition by applying behavioral constraints. Finally, the body elevation was estimated using a pattern-enhancing algorithm applied on BP. The patients were videotaped for reference. The performance of the algorithm was estimated using the Correct Classification Rate (CCR) and F-score. The BP-based classification approach was benchmarked against a previously-published fuzzy-logic classifier (FIS-IMU) and a conventional epoch-based classifier (EPOCH). Results: The algorithm performance for posture/activity detection, in terms of CCR was 90.4 %, with 3.3 % and 5.6 % improvements against FIS-IMU and EPOCH, respectively. The proposed classifier essentially benefits from a better recognition of standing activity (70.3 % versus 61.5 % [FIS-IMU] and 42.5 % [EPOCH]) with 98.2 % CCR for body elevation estimation. Conclusion: The monitoring and recognition of daily activities in mobility-impaired stoke patients can be significantly improved using a trunk-fixed sensor that integrates BP, inertial sensors, and an event-based activity classifier

    Development and Psychometric Properties of A Screening Tool for Assessing Developmental Coordination Disorder in Adults

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    Background: Developmental Coordination Disorder (DCD) is a neurodevelopmental disorder affecting motor coordination. Evidence suggests this disorder persists into adulthood and may be associated with biomechanical dysfunction and pain. We report on the development and initial validation of a questionnaire to assess for DCD in adults. Methods: An initial item pool (13 items) was derived from the American Psychiatric Association criteria and World Health Organisation definition for DCD. An expert panel assessed face and content validity which led to a 9-item Functional Difficulties Questionnaire (FDQ-9) with possible scores ranging from 9-36 (higher scores indicating greater functional difficulties). The FDQ-9 was piloted on individuals recruited from convenience samples. The underlying factor structure and aspects of reliability, validity and accuracy were tested. The Receiver Operating Characteristic Curve was employed to evaluate the diagnostic accuracy of the test using self-reported dyspraxia as the reference standard. Results: Principal Axis Factoring yielded a two factor solution relating to gross and fine motor skills; for conceptual parsimony these were combined. Internal reliability was high (0.81), the mean inter-item correlation was 0.51 and preliminary findings suggested satisfactory construct validity. The Area under the Curve was 0.918 [95% CI 0.84-1.00] indicating a diagnostic test with high accuracy. A cut-off score was established with a sensitivity and specificity of 86% [95% CI 78%-89%] and 81% [95 % CI 73%-89%] respectively. Test-retest reliability was good (ICC 0.96 [95% CI 0.92 to 0.98]. Conclusion: The psychometric properties of the FDQ-9 appear promising. Work is required to conduct further psychometric evaluations on new samples and apply the scale to clinical practice

    Biomechanics

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    Biomechanics is a vast discipline within the field of Biomedical Engineering. It explores the underlying mechanics of how biological and physiological systems move. It encompasses important clinical applications to address questions related to medicine using engineering mechanics principles. Biomechanics includes interdisciplinary concepts from engineers, physicians, therapists, biologists, physicists, and mathematicians. Through their collaborative efforts, biomechanics research is ever changing and expanding, explaining new mechanisms and principles for dynamic human systems. Biomechanics is used to describe how the human body moves, walks, and breathes, in addition to how it responds to injury and rehabilitation. Advanced biomechanical modeling methods, such as inverse dynamics, finite element analysis, and musculoskeletal modeling are used to simulate and investigate human situations in regard to movement and injury. Biomechanical technologies are progressing to answer contemporary medical questions. The future of biomechanics is dependent on interdisciplinary research efforts and the education of tomorrow’s scientists

    Kinematic analysis of reaching movements of the upper limb after total or reverse shoulder arthroplasty

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    Studies have analyzed three-dimensional complex motion of the shoulder in healthy subjects or patients undergoing total shoulder arthroplasty (TSA) or reverse shoulder arthroplasty (RSA). No study to date has assessed the reaching movements in patients with TSA or RSA. Twelve patients with TSA (Group A) and 12 with RSA (Group B) underwent kinematic analysis of reaching movements directed at four targets. The results were compared to those of 12 healthy subjects (Group C). The assessed parameters were hand-to-target distance, target-approaching velocity, humeral-elevation angular velocity, normalized jerk (indicating motion fluidity), elbow extension and humeral elevation angles. Mean Constant score increased by 38 points in Group A and 47 in Group B after surgery. In three of the tasks, there were no significant differences between healthy subjects and patients in the study groups. Mean target-approaching velocity and humeral-elevation angular velocity were significantly greater in the control group than in study groups and, overall, greater in Group A than Group B. Movement fluidity was significantly greater in the controls, with patients in Group B showing greater fluidity than those in Group A. Reaching movements in the study groups were comparable, in three of the tasks, to those in the control group. However, the latter performed significantly better with regard to target-approaching velocity, humeral-elevation angular velocity and movement fluidity, which are the most representative characteristics of reaching motion. These differences, that may be related to deterioration of shoulder proprioception after prosthetic implant, might possibly be decreased with appropriate rehabilitation

    Osseointegrated prostheses for rehabilitation following amputation : The pioneering Swedish model.

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    The direct attachment of osseointegrated (OI) prostheses to the skeleton avoids the inherent problems of socket suspension. It also provides physiological weight bearing, improved range of motion in the proximal joint, as well as osseoperceptive sensory feedback, enabling better control of the artificial limbs by amputees. The present article briefly reviews the pioneering efforts on extremity osseointegration surgeries in Sweden and the development of the OPRA (Osseointegrated Prostheses for the Rehabilitation of Amputees) program. The standard implant design of the OPRA system and surgical techniques are described as well as the special rehabilitation protocols based on surgical sites. The results of long-term follow-up for transradial, transhumeral, and thumb amputee operations are briefly reported including the prospective study of transfemoral amputees according to OPRA protocol. The importance of refinement on implant designs and surgical techniques based on the biomechanical analysis and early clinical trials is emphasized. Future aspects on osseointegration surgery are briefly described, including novel treatment options using implanted electrodes

    Future footwear : the birth of feet, the re-birth of footwear

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    Workshop on Exercise Prescription for Long-Duration Space Flight

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    The National Aeronautics and Space Administration has a dedicated history of ensuring human safety and productivity in flight. Working and living in space long term represents the challenge of the future. Our concern is in determining the effects on the human body of living in space. Space flight provides a powerful stimulus for adaptation, such as cardiovascular and musculoskeletal deconditioning. Extended-duration space flight will influence a great many systems in the human body. We must understand the process by which this adaptation occurs. The NASA is agressively involved in developing programs which will act as a foundation for this new field of space medicine. The hallmark of these programs deals with prevention of deconditioning, currently referred to as countermeasures to zero g. Exercise appears to be most effective in preventing the cardiovascular and musculoskeletal degradation of microgravity
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