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Your query "compressive" produced 17 result(s).
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Smith, Casey (June 30, 2006)[more][less]
Abstract: Reliable and comparable biomechanical testing of total ankle replacement (TAR) systems can only be accomplished with an accurate standardized simulation of ankle mechanics. Information about the kinetics and forces acting on the tibiotalar joint is vital to developing accurate and comparable simulations. Current simulation models rely on extrapolation of 2D force plate information or on mathematical model predictions to approximate the forces at this joint. The main goal of this project was to design an implantable force sensor to isolate and directly measure the axial compressive force acting on the tibiotalar joint during the gait cycle. The ultra high molecular weight polyethylene (UHMWPE) mobile bearing of the Scandinavian Total Ankle Replacement (STAR) was chosen for modification due to the design’s inherent isolation of the axial compressive force. Initial design has focused on creating a radiopaque fluid force sensor that can give reliable and repeatable force measurements at the tibiotalar joint after implantation. The force sensor can be monitored in vivo using fluoroscopic video methods allowing force measurements during weight bearing movements of the ankle joint. Using this data, 2D pattern recognition techniques can be used to recreate a 3D model of the TAR components and model the ankle kinematics corresponding to the compressive force information. Design is currently in the preliminary, feasibility testing stages. Initial tests support the feasibility of the design, but additional design modification and feasibility tesing are required to optimize and validate the design. Description: Musculoskeletal Room G027 Dykes 11:24 AM Abstract 172 URI: http://hdl.handle.net/2271/149 Files in this item: 1
11_24_Smith_172.ppt (14.66Mb) -
Boswell, Scott (June 30, 2006)[more][less]
Abstract: Purpose: To see if locking compression T-plates applied dorsally are stiffer and/or stronger than dorsal non-locking T-plates on a dorsally comminuted distal radius fracture model. Locking plates are thought to have mechanical advantages such as decreased incidence in loss of reduction and improved bone healing. Due to these theoretical advantages, this study seeks to determine any difference in the strength or stiffness of the two plates. Methods: 16 pairs of embalmed cadaveric human radii were potted, and a standard wedge osteotomy was performed simulating a dorsal comminuted fracture. They were randomized into 2 groups, so that 8 pair received a 3.5mm dorsal locking T-plate over the osteotomy on the right radius, and 8 pair received the same on the left radius. A dorsal 3.5mm non-locking compression plate was placed over the osteotomy on the contralateral radius in each group. An axial load was used to test the strength and stiffness of each plate. Results: A significant difference was found in both the stiffness (p=.007) and the strength (p=.001) between the locking and non-locking plates. The locking plate was found to be 33% stiffer than the non-locking plate. The locking plate was found to have an 89% increase in the Load to Failure. Failure for both locked and non-locked plates occurred via volar cortex bone fracture. Conclusion: Locking plates increased both the stiffness and the strength of dorsally comminuted distal radius fractures compared with non-locking plates by a statistically significant margin (p<.05). Description: Musculoskeletal Room G027 Dykes 10:00 AM Abstract 112 URI: http://hdl.handle.net/2271/144 Files in this item: 1
10_00_Boswell_112.ppt (8.997Mb) -
Elhomsy, Georges C; Wehbe, Edgard (February 27, 2008)[more][less]
URI: http://hdl.handle.net/2271/326 Files in this item: 1
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Wootton, R; Loane, M; Mair, F; Allen, A; Doolittle, G; Begley, M; McLernan, A; Moutray, M; Harrison, S (Royal Society of Medicine Press, NaN, 1998)[more][less]
Abstract: Nursing notes for patients nursed at home in the USA and the UK were reviewed using an abstraction instrument developed and tested in the US. More than 1700 episodes of patient care at home were reviewed: 906 in the US and 839 in the UK. Preliminary data suggest that in the US approximately 45% of home nursing visits could be done via telemedicine, while the figure is lower in the UK, less than 15%. Pilot trials of an analogue video-telephone in Kansas City and Belfast suggest that even relatively low-quality compressed video may be useful for home nursing. Clearly, there are differences between the two countries which merit further study, but there is evidence to suggest that telemedicine may have a role in the delivery of home health care. URI: http://hdl.handle.net/2271/314 Files in this item: 0
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Unknown author (February 27, 2008)[more][less]
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Chehab, Bassem M; Salyers, William J (May 22, 2008)[more][less]
URI: http://hdl.handle.net/2271/342 Files in this item: 1
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Wootton, R; Loane, M; Mair, F; Moutray, M; Harrison, S; Sivananthan, S; Allen, A; Doolittle, GC; McLernan, A (Royal Society of Medicine Press, NaN, 1998)[more][less]
Abstract: We assessed the proportion of home nursing visits that could be replaced by home telenursing in the UK. A retrospective review of nursing notes in the UK was undertaken using an abstraction instrument developed and tested in the US. A total of 1951 episodes of patient care at home were reviewed: 1450 from Liverpool and 501 from Belfast. A total of 1626 (83%) of the episodes involved 'hands-on' interventions. In Belfast two observers estimated that 14% of home nursing visits could be done via telemedicine while in Liverpool two more observers gave an estimate of 16%. Inter-rater agreement was high (kappa = 0.93 for the Belfast observers and 0.79 for the Liverpool observers). Pilot trials of an analogue video-phone in Belfast suggested that even relatively low-quality compressed video might be useful for home nursing. These findings suggest that telemedicine may have a significant role in the delivery of home health care in the UK. URI: http://hdl.handle.net/2271/316 Files in this item: 0
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John Ratliff; Neel Anand; Alexander Vaccaro; Moe Lim; Joon Lee; Paul Arnold; James Harrop; Raja Rampersaud; Christopher Bono; Ralf Gahr; Trauma Study Group Spine (BioMedCentral, July 9, 2007)[more][less]
Abstract: BACKGROUND:Considerable variability exists in clinical approaches to thoracolumbar fractures. Controversy in evaluation and nomenclature contribute to this confusion, with significant differences found between physicians, between different specialties, and in different geographic regions. A new classification system for thoracolumbar injuries, the Thoracolumbar Injury Severity Score (TLISS), was recently described by Vaccaro. No assessment of regional differences has been described. We report regional variability in use of the TLISS system between United States and non-US surgeons.METHODS:Twenty-eight spine surgeons (8 neurosurgeons and 20 orthopedic surgeons) reviewed 56 clinical thoracolumbar injury case histories, which included pertinent imaging studies. Cases were classified and scored using the TLISS system. After a three month period, the case histories were re-ordered and the physicians repeated the exercise; 22 physicians completed both surveys and were used to assess intra-rater reliability. The reliability and treatment validity of the TLISS was assessed. Surgeons were grouped into US (n = 15) and non-US (n = 13) cohorts. Inter-rater (both within and between different geographic groups) and intra-rater reliability was assessed by percent agreement, Cohen's kappa, kappa with linear weighting, and Spearman's rank-order correlation.CONCLUSION:Non-US surgeons were found to have greater inter-rater reliability in injury mechanism, while agreement on neurological status and posterior ligamentous complex integrity tended to be higher among US surgeons. Inter-rater agreement on management was moderate, although it tended to be higher in US-surgeons. Inter-rater agreement between US and non-US surgeons was similar to within group inter-rater agreement for all categories. While intra-rater agreement for mechanism tended to be higher among US surgeons, intra-rater reliability for neurological status and PLC was slightly higher among non-US surgeons. Intra-rater reliability for management was substantial in both US and non-US surgeons. The TLISS incorporates generally accepted features of spinal injury assessment into a simple patient evaluation tool. The management recommendation of the treatment algorithm component of the TLISS shows good inter-rater and substantial intra-rater reliability in both non-US and US based spine surgeons. The TLISS may improve communication between health providers and may contribute to more efficient management of thoracolumbar injuries. URI: http://www.wjes.org/content/2/1/24 Files in this item: 1
1749-7922-2-24.pdf (346.7Kb) -
El Bizri, Issam; Massey, Andrew D; Reynolds, Teresa (February 25, 2009)[more][less]
URI: http://hdl.handle.net/2271/569 Files in this item: 1
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Karla Hutt; Zhanquan Shi; David Albertini; Brian Petroff (BioMedCentral, March 10, 2005)[more][less]
Abstract: BACKGROUND:Environmental toxicants, whose actions are often mediated through the aryl hydrocarbon receptor (AhR) pathway, pose risks to the health and well-being of exposed species, including humans. Of particular concern are exposures during the earliest stages of development that while failing to abrogate embryogenesis, may have long term effects on newborns or adults. The purpose of this study was to evaluate the effect of maternal exposure to the AhR-specific ligand 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on the development of rat pre-implantation embryos with respect to nuclear and cytoskeletal architecture and cell lineage allocation.RESULTS:We performed a systematic 3 dimensional (3D) confocal microscopy analysis of rat pre-implantation embryos following maternal exposure to environmentally relevant doses of TCDD. Both chronic (50 ng/kg/wk for 3 months) and acute (50 ng/kg and 1 µg/kg at proestrus) maternal TCDD exposure disrupted morphogenesis at the compaction stage (8–16 cell), with defects including monopolar spindle formation, f-actin capping and fragmentation due to aberrant cytokinesis. Additionally, the size, shape and position of nuclei were modified in compaction stage pre-implantation embryos collected from treated animals. Notably, maternal TCDD exposure did not compromise survival to blastocyst, which with the exception of nuclear shape, were morphologically similar to control blastocysts.CONCLUSION:We have identified the compaction stage of pre-implantation embryogenesis as critically sensitive to the effects of TCDD, while survival to the blastocyst stage is not compromised. To the best of our knowledge this is the first in vivo study to demonstrate a critical window of pre-implantation mammalian development that is vulnerable to disruption by an AhR ligand at environmentally relevant doses. URI: http://www.biomedcentral.com/1471-213X/8/1 Files in this item: 1
1471-213X-8-1.pdf (1.496Mb)
