Mechanical Analysis of Posterior Pedicle Screw System Placement and Internal Fixation in the Treatment of Lumbar Fractures

<table class="table-group" id="tab2"><tr><td><table class="table"><tr><td class="thead-hr" colspan="4"><hr/></td></tr><tr class="thead"><td class="align_left">Group</td><td class="align_center">Preoperative</td><td class="align_center">Postoperative</td><td class="align_center">After 1 year</td></tr><tr><td class="thead-hr" colspan="4"><hr/></td></tr><tr><td class="align_left">Anterior</td><td class="align_center"><span style="width: 50.8374ptpx;"><svg height="8.69875pt" id="M7" style="vertical-align:-0.3499298pt" version="1.1" viewbox="-0.0498162 -8.34882 50.8374 8.69875" width="50.8374pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M412 140C382 77 369 73 315 73H129L270 222C362 320 402 379 402 466C402 571 322 635 234 635C177 635 130 609 99 576L42 495L64 475C90 514 133 568 201 568C274 568 318 519 318 435C318 349 255 267 193 193C144 135 87 78 32 23V0H405C417 45 427 89 440 131L412 140Z"></path></g><g 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493L597 494C603 551 612 629 620 675Z"></path></g></svg> value</td><td class="align_center">0.757</td><td class="align_center">0.574</td><td class="align_center">9.343</td></tr><tr><td class="align_left"><svg height="8.68572pt" id="M14" style="vertical-align:-0.0498209pt" version="1.1" viewbox="-0.0498162 -8.6359 8.15071 8.68572" width="8.15071pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M600 480C600 590 528 650 384 650H143L137 622C222 614 225 607 210 531L130 127C113 41 106 36 23 28L17 0H294L300 28C204 36 195 42 212 127L243 284L314 263C327 263 339 263 352 264C465 271 600 337 600 480ZM508 481C508 351 402 304 329 304C289 304 265 311 250 317L295 559C302 594 310 606 323 611C335 616 350 619 367 619C455 619 508 573 508 481Z"></path></g></svg> value</td><td class="align_center">0.452</td><td class="align_center">0.567</td><td class="align_center">0.001</td></tr><tr class="table-tr"><td colspan="4"><hr class="tbody-hr"/></td></tr></table></td></tr></table>

<div>The changes of Cobb angle before and after operation were compared between the two groups.</div>

Computational and Mathematical Methods in Medicine

tab2

Table 2

Table 2: Mechanical Analysis of Posterior Pedicle Screw System Placement and Internal Fixation in the Treatment of Lumbar Fractures 