Pin loosening in external skeletal fixation : a biomechanical and microstructural comparison of the near and far cortex pin-bone interfaces : a thesis /
ABSTRACT: This study compared the pin-bone interfaces at the near and far-cortical penetration sites within canine tibiae following low speed power insertion of positive-profile, end-threaded pins. A system was developed to allow the independent measurement of holding power of pins within each cor...
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| Format: | Thesis Book |
| Language: | English |
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College Station, TX :
Texas A&M University,
1993.
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| Summary: | ABSTRACT: This study compared the pin-bone interfaces at the near and far-cortical penetration sites within canine tibiae following low speed power insertion of positive-profile, end-threaded pins. A system was developed to allow the independent measurement of holding power of pins within each cortical surface. Scanning electron microscopy was utilized to compare differences in microstructural damage between the near and far-cortical penetration sites. The far-cortical penetration site provided a greater resistance to axial pin extraction than did the near-cortical site (p=0.0059). When normalized for cortical thickness, the far-cortical penetration site was again more resistant to extraction of the pin than the near-cortical site (p=0.0059). Scanning electron microscopic evaluation revealed greater bone microcracking and bone debris and less direct pin-bone contact in the near-cortical sites than in the far-cortical sites. The results of this study suggest that a significant disparity exists between the contribution of the near and far-cortical pin penetration sites to the holding power of positive-profile, two-cortex, end-threaded pins and that the near-cortical site incurs more mechanical damage as a result of pin insertion. |
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| Item Description: | "Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of Master of Science August 1993". "Major subject: Veterinary Medicine and Surgery". Approved as to style and content by: Donald A. Hulse, Ross H. Palmer, Margaret R. Slater, William A. Hyman, John R. August. Vita. |
| Physical Description: | ix, 30 leaves : ills., photographs (mostly color) ; 28 cm. |
| Bibliography: | Includes bibliographical references (leaves 27-29). |