Minimal invasive surgical technique in midline lumbar inter-body fusion: A technique note.

Midline lumbar inter-body fusion (MIDLF) surgery with cortical bone trajectory (CBT) screw insertion is a modern fusion technique for spinal surgery. The difference in entry point of this trajectory from conventional pedicle screw surgery offers the potential benefits of less soft tissue dissection and reduced blood loss, post-operative wound pain, and infection risks. Because this is a newly developed technique first announced by Santoni in 2009, most surgeons perform this surgery in a mini-open fashion and require more intra-operative fluoroscopy and ionizing radiation exposure during screw placement. In this article, we demonstrate a minimally invasive midline lumbar interbody fusion (MIS-MIDLF) technique with percutaneous CBT screw placement. Using a designed cannulated awl, we only need a single dimensional fluoroscopy view from anterior to posterior (AP view) to achieve an accurate trajectory and therefore reduce radiation exposure. We report our first ten consecutive patients with degenerative spondylolithesis who underwent MISS-MIDLF and were followed up for more than 18 months. The procedure required a single wound of about 3 cm in length in one to two level fusion surgery and only three to four shots of fluoroscopy were needed for each screw placement. There were no screws malpositioned in subsequent plain films or computer tomography scans. We demonstrate a case with detailed surgical procedures and provide this technique as an alternative approach for surgeons performing MILDF surgery.

Cortical bone trajectory screws fixation in lumbar adjacent segment disease: A technique note with case series.

Lumbar adjacent segment disease after lumbar fusion surgery often requires surgical intervention. However, subsequent surgical treatment often needs to expose and remove all of the previous instruments. This additional surgery leads to significant post-operative pain, muscular fibrosis, poor wound healing and infection, etc. From October 2015 to March 2016, we collected six cases underwent cortical bone trajectory screws fixation with minimal invasive inter-body cage fusion for lumbar adjacent segment disease. Patients in the study all had improvement after surgery without recurrence or instruments failure during follow-up. The technique negates removal of pre-existing instruments and when combined with minimal invasive fusion surgery, the wound length, blood loss and soft tissue damage could be reduced compared with traditional surgery. We introduce the surgical procedures in detail and wish this technique could be an option for spine surgeons who encounter a similar situation.