scholarly journals Quantifying Forearm Soft Tissue Motion from Massless Skin Markers following Forward Fall Hand Impacts

Author(s):  
Danielle L. Gyemi ◽  
Don Clarke ◽  
Paula M. van Wyk ◽  
William J. Altenhof ◽  
David M. Andrews

Background: Investigating soft tissue motion related to impact events is important for understanding how the body mitigates potentially injurious forces through shock attenuation. Objectives: The aims of this study were to: 1) quantify displacement and velocity of the forearm soft tissues following forward fall impacts; and 2) compare two massless skin marker designs (single layer, uniform (SLU) design; stacked, non-uniform (SNU) design) in terms of how well they could be tracked over varying skin pigmentations using automated motion capture software. Methods: Two participant groups (skin pigmentation: light – 9F, 8M; dark – 9F, 6M) underwent simulated forward fall hand impacts for each marker design using a torso-release apparatus. Marker positions associated with planar motion of forearm soft tissues during impact were automatically tracked (ProAnalyst®) in the proximal-distal and anterior-posterior axes from high speed recordings (5000 f/s). Mean peak displacements and velocities for eight forearm regions were then calculated (LabVIEW®). Results: Overall, soft tissue displacement and velocity increased from distal to proximal forearm regions. The greatest displacement (1.47 cm) and velocity (112.8 cm/s) occurred distally toward the wrist. Soft tissue impact responses between sexes did not differ, on average (p > 0.05). The SLU and SNU markers produced different kinematic values (p < 0.05); however, the magnitudes of, and consequently meaningfulness of these statistical differences for automatically tracking soft tissue motion, were negligible (displacement: ≤ 0.05 cm; velocity: ≤ 2.5 cm/s). Conclusions: Forearm soft tissue motion was successfully quantified for forward fall hand impacts; both marker designs were deemed functionally equivalent.

2002 ◽  
Vol 18 (3) ◽  
pp. 231-242 ◽  
Author(s):  
Matthew T.G. Pain ◽  
John H. Challis

The aims of this study were to quantify intrasegmental motion using an array of 28 surface-mounted markers to examine frequency and amplitude measurements of the intrasegmental motion to calculate forces and energy transfer; and to show that the underlying muscles are a major contributor to the skin marker motion. One participant performed 27 trials under three conditions in which his forearm was struck against a solid object fixed to a force plate while the locations of the markers were recorded at 240 Hz. For impacts with equal peak forces, the muscle tension significantly affected the amount of intrasegmental motion. Tensing the arm reduced the intrasegmental motion by 50%. The quadrilateral sectors defined by the markers changed in area by 11% with approximately equal motion in the vertical and horizontal direction. The maximum linear marker motion was 1.7 cm. The intrasegmental motion had distinct frequency components around 14 and 20 Hz. Soft tissue deformation could account for 70% of the energy lost from the forearm during these impacts. The study has demonstrated the important role that intrasegment soft tissue motion can have on the kinetics of an impact.


Author(s):  
Zulkarnay Zakaria ◽  
Mohd Fahajumi Jumaah ◽  
Mohd Saiful Badri Mansor ◽  
Khairi Mat Daud ◽  
Mohd Hafiz Fazalul Rahiman ◽  
...  

Terapi merupakan antara teknik perubatan tertua dalam mengekalkan kesihatan badan terutama daripada aliran darah yang tidak baik, strok dan beberapa penyakit yang lain. Teknik ini termasuklah akupuntur, guasa dan juga urutan. Terdapat juga teknik terapi moden seperti terapi warna, terapi ozon, terapi dadah dan banyak lagi. Kertas kajian ini akan mengetengahkan penjana terapi elektromagnet, satu alat yang mempunyai potensi aplikasi terapi dalam bidang perubatan. Alat ini menghasilkan medan magnet berfrekuensi sederhana sebagai sumber terapi. Perkakasan yang berskala kecil berfrekuensi sederhana dan berkos rendah ini telah dibangunkan dan telah diuji pada tisu biologi bagi mengukur tahap ketembusan medan magnet. Ujian ini telah membuktikan bahawa medan magnet yang telah dihasilkan mampu menembusi tisu lembut bersaiz sehingga 2 cm dengan jarak 7 cm daripada sumber. Kebolehan penembusan sistem ini terhadap tisu lembut memberikan peluang yang cerah kepada kajian ini memandangkan medan magnet telah menunjukkan potensi sebagai sebahagian daripada terapi untuk memulihkan migraine, strok, kekejangan dan beberapa yang lain selain boleh diaplikasikan dalam pengimejan tomografi induksi magnet. Kata kunci: Terapi elektromagnet, medan magnet, penembusan, tisu lembut, aplikasi perubatan Therapy is among the oldest medication technique in maintaining the health of the body especially from bad blood circulation, stroke and several others. This technique includes acupuncture, guasa and also massage. There are also modern therapy techniques like colour therapy, water therapy, ozone therapy, drug therapy and others. This paper will highlight electromagnetic therapy generator, a device which has the potential of therapy application in medical field. This device produce medium frequency magnetic field as a therapy source. This small scale medium frequency and low cost hardware that has been developed was tested on the biological tissue for the purpose of measuring the magnetic field penetration. The testing has proven that the generated magnetic field is able to penetrate the soft tissue up to 2 cm with distance from the source up to 7 cm. The capability of the system penetrations through the soft tissues provide the bright future of this research since magnetic field have shown the potential as being part of the therapy for curing migraine, stroke, cramp and several others besides the application in the magnetic induction tomography imaging. Key words: Electromagnetic therapy, magnetic field, penetration, soft tissue; medical applications


2019 ◽  
Vol 186 (2) ◽  
pp. 66-66 ◽  
Author(s):  
Ming Lu ◽  
Cheng-Chung Lin ◽  
Tung-Wu Lu ◽  
Shi-Nuan Wang ◽  
Ching-Ho Wu

Skin marker-based motion analysis has been widely used to evaluate the functional performance of canine gait and posture. However, the interference of soft tissues between markers and the underlying bones (soft tissue artefacts, STAs) may lead to errors in kinematics measurements. Currently, no optimal marker attachment sites and cluster compositions are recommended for canine gait analysis. The current study aims to evaluate cluster-level STAs and the effects of cluster compositions on the computed stifle kinematics. Ten mixed-breed healthy dogs affixed with 19 retroreflective markers on the thigh and shank were enrolled. During isolated stifle passive extension, the marker trajectories were acquired with a motion capture system, and the skeletal poses were determined by integrating fluoroscopic and CT images of the bones. The cluster-level STAs were assessed, and clusters were paired to calculate the stifle kinematics. A selection of cluster compositions was useful for deriving accurate sagittal and frontal plane stifle kinematics with flexion angles below 50 per cent of the range of motion. The findings contribute to improved knowledge of canine STAs and their influence on motion measurements. The marker composition with the smallest error in describing joint kinematics is recommended for future applications and study in dogs during dynamic gait assessment.


2013 ◽  
Vol 40 (9) ◽  
pp. 091713 ◽  
Author(s):  
Joerg Rottmann ◽  
Paul Keall ◽  
Ross Berbeco

2016 ◽  
Vol 11 (12) ◽  
pp. 2325-2337 ◽  
Author(s):  
Andreas Schoob ◽  
Max-Heinrich Laves ◽  
Lüder Alexander Kahrs ◽  
Tobias Ortmaier

2017 ◽  
Vol 40 ◽  
pp. 80-95 ◽  
Author(s):  
Andreas Schoob ◽  
Dennis Kundrat ◽  
Lüder A. Kahrs ◽  
Tobias Ortmaier

1990 ◽  
Vol 112 (4) ◽  
pp. 371-378 ◽  
Author(s):  
T. P. Quinn ◽  
C. D. Mote

An acoustic transducer design to measure the relative translations and rotations across the knee with no mechanical coupling between the tibia and femur is presented. Platforms attached to femoral and tibial tracking fixtures hold acoustic sources and receivers, respectively. The distance from each source to each receiver is measured by the acoustic transit time and the translations and rotations across the knee joint are computed. For rotations less than 30 deg around the expected operating position, the resolution of the transducer is 0.3 deg; for translations less than 1.5 cm around the expected operating position, the resolution is 0.03 cm. Theoretical error analysis using a Monte Carlo method shows that the uncertainty in the measurement depends on the relative position of the sources and receivers. The analysis predicts the worst case resolution of the transducer as 0.09 cm in translation and 0.6 deg in rotation when the receiver platform is translated 8.0 cm parallel to the source platform. The transducer and fixturing system are demonstrated on a cadaver specimen for applied anterior force and applied internal-external rotation. Errors due to (soft tissue) motion of the transducer relative to the bone during in vivo measurements are assessed on the cadaver specimen. For internal-external rotation the error due to soft tissue motion is a maximum of 0.5 cm in translation and 1.8 deg in rotation. For applied anterior force the error due to soft tissue motion is a maximum of 0.16 cm in translation and 2.7 deg in rotation.


2020 ◽  
Vol 71 (8) ◽  
pp. 292-303
Author(s):  
Madalina Preda ◽  
Alina-Alexandra Serbanescu ◽  
Mara Madalina Mihai ◽  
Gabriela-Loredana Popa ◽  
Loredana Cornelia Sabina Manolescu ◽  
...  

Staphylococcus spp. is a facultative pathogen, which can be found in the commensal microbiota of humans, most often in moist skinfolds and mucous membranes. This microorganism has the ability to cause various infections, in almost every organ of the body, with an increased frequency in the skin and soft tissues, being involved in pathologies like acne, folliculitis, furunculosis, hidradenitis suppurativa, cellulitis, abscesses, but also in secondary infections in diseases with an altered cutaneous barrier. The prolonged evolution of these diseases and severe outcome can be influenced by various factors, most importantly being the antimicrobial resistance. We have evaluated the antimicrobial susceptibility profiles, according to the Comite de l` Antibiogramme de la Societe Francaise de Microbiologie recommendations, for strains of Staphylococcus spp. isolated from acne or different types of skin and soft tissue infections in patients recommended to receive autologous bacterial vaccine. Most frequent identified species was Staphylococcus epidermidis, followed by Staphylococcus aureus. The antimicrobial resistance was higher for antibiotics usually used in the treatment of skin and soft tissue infections, with interesting differences of the resistance profile for the strains isolated from patients before receiving autologous bacterial vaccine compared with the ones from individuals already treated. Another important finding was represented by the differences in the resistance profile according to the age group of the patients. The results of this study underline the importance of antimicrobial resistance surveillance in finding new molecules and alternative therapies, the necessity of a personalized approach in medical acts and of a continuous connection between clinic and laboratory research.


2008 ◽  
Vol 36 (2) ◽  
pp. 71-75 ◽  
Author(s):  
John H. Challis ◽  
Matthew T.G. Pain

1968 ◽  
Vol 71 (3) ◽  
pp. 303-310 ◽  
Author(s):  
A. C. Field ◽  
N. F. Suttle ◽  
R. G. Gunn

SUMMARYGroups of ewes kept under hill conditions were killed at intervals during October to July 1965–66. Supplementary feed was given between February and May. The carcasses were divided into soft tissue, uterus and its contents and skeletal fractions. Each fraction was dissolved in HNO3 and its fat and mineral content measured. The sheep were heavier in November and lighter in May during lactation than at other times. The content of fat in the body fell progressively from October to May and then increased; initially fat was withdrawn only from the soft tissues but by April and May the fat contents of both skeleton and soft tissues were exceedingly low. The weight of fatfree soft tissue remained relatively constant but was heaviest in July. Fat-free skeleton fraction was lighter in January than in April.The contents of the predominantly intracellular ions, P, Mg and K in the soft tissue fell between November and January, remained constant between January and May and then increased. There was an increase in Na towards the end of pregnancy followed by a marked fall after parturition. The contents of Ca and P in the skeleton fell between November and January and during lactation between April and July. There was a marked increase between February and April when supplementary feeding was given. Evidence that Mg was selectively removed from the skeleton was obtained in November and January, two sheep having Ca:Mg ratios in skeleton greater than 100. Na and K contents of the skeleton were greatest at the end of pregnancy in April. For the lambs between 6 and 23 kg live weight, each kg of live-weight gain contained 8·8 g Ca, 5·0 g P, 0·27 g Mg, 0·83 g Na and 1·85 g K.


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