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The central research question was whether preoperative planning based on bone mineral density (BMD) can enhance screw fixation strength and potentially reduce the risk of loosening.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>A biomechanical cadaveric study was conducted using thirty human vertebrae. Each vertebra was instrumented with one pedicle screw using a standard trajectory and another using a BDO trajectory. Two trajectory types were tested: traditional trajectory (TT) and cortical bone trajectory (CBT). Screw stability was assessed by mechanical pullout testing, measuring the ultimate force required to extract each screw.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      BDO trajectories significantly improved screw pullout strength in both trajectory types. For TT screws, the median increase in pullout force was 43.1% (interquartile range [IQR]: 10.1%, 108.3%;\n                      <jats:italic>p<\/jats:italic>\n                      \u2009=\u2009\u20090.004). For CBT screws, the median increase was 37.0% (IQR: \u22121.5%, 122.6%;\n                      <jats:italic>p<\/jats:italic>\n                      \u2009=\u20090.034).\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Bone density-optimized pedicle screw trajectories significantly enhance screw fixation strength in both traditional and cortical trajectories. These findings support the use of personalized, BMD-informed surgical planning to improve spinal fusion outcomes and reduce the incidence of screw loosening.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1007\/s00586-025-09170-8","type":"journal-article","created":{"date-parts":[[2025,7,29]],"date-time":"2025-07-29T04:24:50Z","timestamp":1753763090000},"page":"2115-2121","update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Bone density-optimized pedicle screw planning enhances mechanical stability"],"prefix":"10.1007","volume":"35","author":[{"given":"Tobias","family":"G\u00f6tschi","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gian","family":"Maranta","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mick","family":"Bernet","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"M\u00e9lanie K.","family":"Zemp","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mazda","family":"Farshad","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jonas","family":"Widmer","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2025,7,29]]},"reference":[{"key":"9170_CR1","doi-asserted-by":"publisher","first-page":"99","DOI":"10.1097\/00003086-198602000-00012","volume":"203","author":"MR Zindrick","year":"1986","unstructured":"Zindrick MR, Wiltse LL, Widell EH et al (1986) A Biomechanical Study of Intrapeduncular Screw Fixation in the Lumbosacral Spine. 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MF reports being a consultant for Arthrex and Medacta, board member and recipient of research support from Medacta and fellowship support from DePuy Synthes. All other authors report no conflicts of interest.","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Competing interests"}}]}}