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BackgroundPhysical exercise, such as walking, is imperative to older adults. However, long-distance walking may increase walking instability which exposes them to some fall risks.ObjectiveTo evaluate the influence of long-distance walking on gait asymmetry and variability of older adults.MethodSixteen physically active older adults were instructed to walk on a treadmill for a total of 60 min. Gait experiments were conducted over-ground at the baseline (before treadmill-walk), after first 30 min (30-min) and second 30 min (60-min) of the walk. In addition to spatiotemporal parameters, median absolute deviation of the joint angular velocity was measured to evaluate gait asymmetry and gait variability.FindingsThere were significant differences in the overall asymmetry index among the three time instances (Partial η2 = 0.77, p < .05), predominantly contributed by the ankle (Partial η2 = 0.31, p < .017). Long-distance walking significantly increased the average and maximum median absolute deviation of the ankle at both sides (W ≥ 0.19, p < .05), and knee at the non-dominant side (W = 0.44, p < .05).Interpretation.At 30-min, the older adults demonstrated a significantly higher asymmetry and variability at the ankle, which implied higher instability. Continue walking for an additional 30 min (60-min) further increased variability of the non-dominant limb at the knee joint. Walking for 30 min or more could significantly reduce walking stability. 相似文献
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《The spine journal》2022,22(11):1759-1767
Despite the advances made in high-resolution spinal imaging, plain films (radiographs or x-rays) remain a cornerstone of evaluating and caring for spine patients in the preoperative, intraoperative, and postoperative settings. Although often undervalued when compared with more advanced imaging such as MRIs or CT scans, plain films provide surgeons invaluable information that other imaging modalities oftentimes cannot. In addition to their use during surgery for localization or evaluation of hardware placement, x-rays provide an overall image of a patient's spine, are useful in evaluating hardware complications, allow detailed assessment of alignment and stability and allow for repeated images in clinic during follow-up. Plain films continue to provide critical information that cannot be obtained with other imaging modalities, and they remain central to providing optimal care for spine patients. 相似文献
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《The surgeon》2020,18(3):165-177
IntroductionThe liver is the most frequently damaged organ in blunt abdominal trauma. It is widely accepted that hemodynamically stable patients with low-grade liver trauma should be treated with non-operative management, however there is controversy surrounding its safety and efficacy in high-grade trauma. The purpose of this review is to investigate the role of non-operative management in patients with high-grade liver trauma.MethodsPubMed and reference lists of PubMed articles were searched to find studies that examined the efficacy of non-operative management in high-grade liver injury patients, and compare it to operative management. Non-operative management was considered successful if rescue surgery was avoided. Outcomes considered were success, mortality, and complication rates.ResultsThe electronic search revealed 2662 records, 8 of which met the inclusion criteria. All 8 studies contained results suggesting that non-operative management was safe and effective in hemodynamically stable patients with high-grade liver trauma. By combining the outcomes of the different studies, non-operative management had a high success rate of 92.4% (194/210) in high-grade liver trauma patients, which was near the overall 95.0% non-operative management success rate. Non-operative management also had mortality and complication rates of 4.6% (9/194) and 9.7% (7/72) in high-grade injury patients, respectively, compared to operative management's 17.6% (26/148) and 45.5% (5/11).ConclusionNon-operative management of liver trauma is safe and effective in hemodynamically stable patients with high-grade liver injury. It is associated with significantly lower mortality compared with operative management. More studies are required to evaluate complications of non-operative management in high-grade liver injury. 相似文献
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《Arthroscopy》2020,36(4):981-982
The use of stem cells in orthopaedics remains a controversial topic, stem cells remain experimental, and significant concerns exist. Studies evaluating diagnoses that may spontaneously resolve could be of low value absent a control group. Only same-day harvest of minimally manipulated stem cells is approved for use in the United States, and these minimally manipulated products may contain insufficient cells to affect outcomes. Extensively cultured cells do not qualify for use in the United States outside of an approved Investigational New Drug Application. Moreover, in other arenas, significant, serious adverse events have been reported after the use of manipulated stem cells. Both the US Food and Drug Administration and American Academy of Orthopaedic Surgeons have recognized the potential for abuse regarding this evolving technology. Published results using stems cells to treat rotator cuff disease are inconsistent, and the optimum source and preparation of the stem cells remains unknown. 相似文献
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《The spine journal》2022,22(11):1903-1912
BACKGROUND CONTEXTThe biomechanical impact of spondylophytes on segmental stiffness is largely unknown, despite their high incidence.PURPOSEThe aim of this study was to quantify the biomechanical contribution according to location and cranio-caudal extent of spondylophytes and to create a clinically applicable radiological classification system.STUDY DESIGNBiomechanical cadaveric study.METHODSTwenty-six cadaveric human lumbar spinal segments with spondylophytes were tested with a displacement-controlled stepwise reduction method. The reduction in load required for the same motion after spondylophyte dissection was used to calculate the biomechanical contribution in flexion, extension, axial rotation, lateral bending, anterior, posterior and lateral shear. The spondylophytes were categorized by assessment of their anatomical position and cranio-caudal extent in computed tomography images (grade 1: spondylophytes spanning less than 50% of the disc-height, grade 2:>50%, grade 3:>90%, grade 4: bony bridging between the vertebrae) by two experienced radiologists. Cohen's kappa (κ) was used to report interreader reliability.RESULTSThe largest biomechanical effect of non-bridging spondylophytes (grade 1–3) was recorded during contralateral bending with a grade-dependent contribution of up to 35%. Other loading directions including ipsilateral bending and translational loading were affected with values below 13%. Spondylophytes with osseous bridging (grade 4) show large contribution to the segmental stiffness in most loading conditions with values reaching over 80%. Interreader agreement for the spondylophyte grading was “substantial” (κ=0.73, p<.001).CONCLUSIONSThe location and cranio-caudal extent of spondylophytes are essential parameters for their biomechanical effect. A reproducible classification has been validated biomechanically and helps evaluate the effect of specific spondylophyte configurations on segmental stiffness.CLINICAL SIGNIFICANCENon-bridging spondylophytes primarily act as tensile structures and do not provide relevant propping. A classification system is presented to support understanding of the biomechanical consequences of different spondylophyte configuration for clinical decision making in surgical planning. 相似文献
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