Minimally Invasive Midline Pars-Cortical Screw Techniques

  • Daniel L. Cavanaugh
  • Kunwar (Kevin) S. Khalsa
  • Nitin Khanna
  • Gurvinder S. DeolEmail author


The cortical screw trajectory is an evolution of the technique used for traditional pedicle screw placement. The novel cortical screw trajectory aims to increase screw purchase with the preferential capture of more cortical bone rather than cancellous bone located within the pedicles. This pathway also has the benefit of a smaller window of exposure required for placement, and thus lends itself for application in minimally invasive techniques. This chapter will explore the biomechanical advantages of cortical screw placement compared to traditional pedicle screws. It will also review the radiographic and anatomic landmarks required for safe insertion. Literature regarding clinical outcomes of cortical screw based procedures will be discussed.


Cortical screw Cortical screw trajectory Minimally invasive fusion Pars screw trajectory 


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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  • Daniel L. Cavanaugh
    • 1
  • Kunwar (Kevin) S. Khalsa
    • 2
  • Nitin Khanna
    • 3
  • Gurvinder S. Deol
    • 4
    Email author
  1. 1.Department of Orthopaedic SurgeryUniversity of North CarolinaChapel HillUSA
  2. 2.Spine DepartmentOrthoArizonaScottsdaleUSA
  3. 3.Orthopaedic Specialists of Northwest IndianaMunsterUSA
  4. 4.Wake OrthopaedicsWakeMed Health and HospitalsRaleighUSA

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