Isthmus-guided cortical bone trajectory for pedicle screw insertion

Area of Science:

• Orthopedics
• Neurosurgery
• Spinal Fusion Techniques

Background:

• Conventional pedicle screw insertion for lumbar fusion involves significant soft tissue disruption.
• Cortical bone trajectory (CBT) presents a novel, less invasive pathway for pedicle screw placement.
• Limitations of original CBT include reliance on the inferior articular process, often compromised in patients needing fusion.

Purpose of the Study:

• To describe a modified cortical bone trajectory (CBT) technique for lumbar vertebral fusion.
• To address limitations of the original CBT approach, particularly regarding reference points and potential nerve root compromise.
• To enhance the safety and applicability of CBT in spinal fusion surgery.

Main Methods:

• Modified CBT technique involves screw insertion lateral to the inferior articular process.
• Utilizes the inferior articular process and isthmus as key anatomical reference points for screw placement.
• Employs side-view X-ray fluoroscopy to ensure screw trajectory avoids the intervertebral foramen and protects neural structures.

Main Results:

• The modified CBT technique allows for screw insertion with reduced soft tissue dissection compared to conventional methods.
• Careful landmark identification and intraoperative imaging mitigate risks associated with compromised anatomical references and lateral slippage.
• The described approach aims to maintain clearance from the intervertebral foramen, safeguarding nerve roots.

Conclusions:

• The refined CBT technique provides a viable, less invasive alternative for pedicle screw fixation in lumbar vertebral fusion.
• This modified approach enhances surgical safety by addressing the challenges posed by degenerative changes and anatomical variations.
• Further clinical evaluation is warranted to establish the long-term efficacy and benefits of this modified CBT technique.