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31.
Raymond E. Chen Emma Knapp Bowen Qiu Anthony Miniaci Hani A. Awad Ilya Voloshin 《Seminars in Arthroplasty》2022,32(1):145-153
BackgroundThe purpose of this study was to compare initial fixation strength between various stemless and stemmed humeral components and to correlate implant fixation strength with bone mineral density (BMD).MethodsFive humeral stem designs were investigated: Stemless-A (four hollow fins), Stemless-B (central body, three solid fins), Stemless-C (central screw, peripheral rim-fit), Short stem (50 mm), and Standard stem (130 mm). Fifty cadaveric human humerii were obtained and divided into five groups. BMD within the humeral head was determined for all samples. The mean BMD was similar between groups. The 25 samples with the lowest and highest BMDs were categorized as “Low” and “High,” respectively, with a BMD threshold of 0.35 g/cm2, creating BMD subgroups. After implantation, each sample underwent a standardized biomechanical testing protocol, with axial loading followed by torsional loading. Sensors attached to the specimen recorded micromotion throughout testing. Axial loading consisted of cyclic loading for 100 cycles at 3 peak forces (220, 520, and 820 N). Torsional loading consisted of 100 cycles of internal/external rotation at 0.1 Hz at 6 peak torques, or until failure (±2.5, 5, 7.5, 10, 12.5, and 15 Nm). Failure was defined as the torque at which any bone fracture, implant detachment from anchor/stem, or an excess of 50° internal/external rotation occurred. Groups and BMD subgroups were compared.ResultsAt maximal axial loading, Stemless-B demonstrated greater micromotion (540 μm) than Stemless-C (192 μm) (P = .003). Stemless-B and Stemless-A (387 μm) also had greater micromotion than Short stem (118 μm, P < .001, P = .03) and Standard stem (85 μm, P < .001, P = .01). When comparing low-BMD samples at maximal axial loading, these differences were accentuated, but comparison of high-BMD samples showed no significant differences between groups. Torsional testing demonstrated that Standard stem failed at greater torque (7.2 Nm) than Stemless-B (2.3 Nm, P < .001), Stemless-A (1.9 Nm, P < .001), and Stemless-C (3.9 Nm, P = .01). When comparing torsional testing results of low-BMD samples, both Standard stem and Short stem failed at greater torque than Stemless-B (P = .02, P = .003) and Stemless-A (P = .03, P = .004) but failed at a similar torque to Stemless-C. Torsional testing of high-BMD samples showed that Standard stem failed at a greater torque than all stemless designs.ConclusionStemless humeral implants should be used with caution in low-BMD settings (<0.35 g/cm2). A central screw and peripheral rim-fit stemless anchor design demonstrated greater fixation strength at low BMD when compared with other designs, while all stemless designs performed similarly at high BMD.Level of evidenceBasic Science Study; Cadaveric Study 相似文献
32.
Two-year results after combined phacoemulsification and iris-fixated phakic intraocular lens removal
Gaurisankar Zoraida Solaiga van Rijn Gwyneth A. Cheng Yanny Y. Y. Luyten Gregorius P. M. Beenakker Jan-Willem M. 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2022,260(4):1367-1375
Graefe's Archive for Clinical and Experimental Ophthalmology - To describe and present results after a technique for cataract surgery combined with explantation of an iris-fixated phakic... 相似文献
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Hassen Lena M. Albarrak Rana A. Albahlal Reem A. Alsaqabi Dimah K. Hassen Ikhlass M. Daghestani Maha H. Alqurtas Eman M. Alkhalaf Abdulaziz T. Bedaiwi Mohammed K. Omair Mohammed A. Almaghlouth Ibrahim A. 《Quality of life research》2022,31(11):3229-3239
Quality of Life Research - The COVID-19 pandemic might add to the stressors experienced by people living with rheumatic diseases. This study aimed to examine rheumatic patients’ functional... 相似文献
36.
Lykov A. P. Uvarov I. P. Gevorgiz R. G. Zheleznova S. N. 《Bulletin of experimental biology and medicine》2022,172(3):301-304
Bulletin of Experimental Biology and Medicine - We studied the effect of microalgae of various systematic groups added to the ration on the biochemical parameters of blood serum and liver and... 相似文献
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Molnár B. Aroca S. Dobos A. Orbán K. Szabó J. Windisch P. Stähli A. Sculean A. 《Clinical oral investigations》2022,26(12):7135-7142
Clinical Oral Investigations - To evaluate t he long-term outcomes following treatment of RT 1 multiple adjacent gingival recessions (MAGR) using the modified coronally advanced tunnel (MCAT) with... 相似文献
39.
Osnat Bairey MD Alisa Taliansky MD Amir Glik MD Alexandra Amiel MD Shlomit Yust-Katz MD Ronit Gurion MD Miri Zektser MD Tzvika Porges MD Nadav Sarid MD Netanel A. Horowitz MD Tzahala Tzuk Shina MD Eyal Lebel MD Amos Cohen MD Karyn Revital Geiger MD Pia Raanani MD Ofir Wolach MD Tali Siegal MD 《Cancer》2023,129(24):3905-3914
40.
This commentary focuses on the emerging intersection between BMP/TGF-β signaling roles in nervous system function and the amyotrophic lateral sclerosis (ALS) disease state. Future research is critical to elucidate the molecular underpinnings of this intersection of the cellular processes disrupted in ALS and those influenced by BMP/TGF-β signaling, including synapse structure, neurotransmission, plasticity, and neuroinflammation. Such knowledge promises to inform us of ideal entry points for the targeted modulation of dysfunctional cellular processes in an effort to abrogate ALS pathologies. It is likely that different interventions are required, either at discrete points in disease progression, or across multiple dysfunctional processes which together lead to motor neuron degeneration and death. We discuss the challenging, but intriguing idea that modulation of the pleiotropic nature of BMP/TGF-β signaling could be advantageous, as a way to simultaneously treat defects in more than one cell process across different forms of ALS. 相似文献