English  |  正體中文  |  简体中文  |  Items with full text/Total items : 66984/66984 (100%)
Visitors : 23059315      Online Users : 315
RC Version 7.0 © Powered By DSPACE, MIT. Enhanced by NTU Library IR team.
Scope Tips:
  • please add "double quotation mark" for query phrases to get precise results
  • please goto advance search for comprehansive author search
  • Adv. Search
    HomeLoginUploadHelpAboutAdminister Goto mobile version


    Please use this identifier to cite or link to this item: http://ir.lib.ncu.edu.tw/handle/987654321/26841


    Title: Comparison and prediction of pullout strength of conical and cylindrical pedicle screws within synthetic bone
    Authors: Tsai,WC;Chen,PQ;Lu,TW;Wu,SS;Shih,KS;Lin,SC
    Contributors: 機械工程研究所
    Keywords: FINITE-ELEMENT ANALYSES;INCREASING BENDING STRENGTH;CANCELLOUS BONE;HOLDING POWER;BIOMECHANICAL TESTS;INSERTIONAL TORQUE;OUT STRENGTH;SPINE;FIXATION;LUMBAR
    Date: 2009
    Issue Date: 2010-06-29 18:01:29 (UTC+8)
    Publisher: 中央大學
    Abstract: Background: This study was designed to derive the theoretical formulae to predict the pullout strength of pedicle screws with an inconstant outer and/or inner diameter distribution ( conical screws). For the transpedicular fixation, one of the failure modes is the screw loosening from the vertebral bone. Hence, various kinds of pedicle screws have been evaluated to measure the pullout strength using synthetic and cadaveric bone as specimens. In the literature, the Chapman's formula has been widely proposed to predict the pullout strength of screws with constant outer and inner diameters (cylindrical screws). Methods: This study formulated the pullout strength of the conical and cylindrical screws as the functions of material, screw, and surgery factors. The predicted pullout strength of each screw was compared to the experimentally measured data. Synthetic bones were used to standardize the material properties of the specimen and provide observation of the loosening mechanism of the bone/screw construct. Results: The predicted data from the new formulae were better correlated with the mean pullout strength of both the cylindrical and conical screws within an average error of 5.0% and R-2 = 0.93. On the other hand, the average error and R-2 value of the literature formula were as high as -32.3% and -0.26, respectively. Conclusion: The pullout strength of the pedicle screws was the functions of bone strength, screw design, and pilot hole. The close correlation between the measured and predicted pullout strength validated the value of the new formulae, so as avoid repeating experimental tests.
    Relation: BMC MUSCULOSKELETAL DISORDERS
    Appears in Collections:[機械工程研究所] 期刊論文

    Files in This Item:

    File Description SizeFormat
    index.html0KbHTML733View/Open


    All items in NCUIR are protected by copyright, with all rights reserved.

    社群 sharing

    ::: Copyright National Central University. | 國立中央大學圖書館版權所有 | 收藏本站 | 設為首頁 | 最佳瀏覽畫面: 1024*768 | 建站日期:8-24-2009 :::
    DSpace Software Copyright © 2002-2004  MIT &  Hewlett-Packard  /   Enhanced by   NTU Library IR team Copyright ©   - Feedback  - 隱私權政策聲明