Can the cortical bone trajectory screw technique be an alternative method to the pedicle screw in posterior lumbar fusion? A systematic review and metaanalysis

Object Symptomatic adjacent-segment lumbar disease (ASLD) after lumbar fusion often requires subsequent surgical intervention. The authors report utilizing cortical bone trajectory (CBT) pedicle screw fixation with intraoperative CT (O-arm) image-guided navigation to stabilize spinal levels in patients with symptomatic ASLD. This unique technique results in the placement of 2 screws in the same pedicle (1 traditional pedicle trajectory and 1 CBT) and obviates the need to remove preexisting instrumentation. Methods The records of 5 consecutive patients who underwent lumbar spinal fusion with CBT and posterior interbody grafting for ASLD were retrospectively reviewed. All patients underwent screw trajectory planning with the O-arm in conjunction with the StealthStation navigation system. Basic demographics, operative details, and radiographic and clinical outcomes were obtained. Results The average patient age was 69.4 years (range 58–82 years). Four of the 5 surgeries were performed with the Minimal Access Spinal Technologies (MAST) Midline Lumbar Fusion (MIDLF) system. The average operative duration was 218 minutes (range 175–315 minutes). In the entire cohort, 5.5-mm cortical screws were placed in previously instrumented pedicles. The average hospital stay was 2.8 days (range 2–3 days) and there were no surgical complications. All patients had more than 6 months of radiographic and clinical follow-up (range 10–15 months). At last follow-up, all patients reported improved symptoms from their preoperative state. Radiographic follow-up showed Lenke fusion grades of A or B. Conclusions The authors present a novel fusion technique that uses CBT pedicle screw fixation in a previously instrumented pedicle with intraoperative O-arm guided navigation. This method obviates the need for hardware removal. This cohort of patients experienced good clinical results. Computed tomography navigation was critical for accurate CBT screw placement at levels where previous traditional pedicle screws were already placed for symptomatic ASLD.

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Comparison of cortical bone trajectory versus pedicle screw techniques in lumbar fusion surgery

Medicine ◽

10.1097/md.0000000000016751 ◽

2019 ◽

Vol 98 (33) ◽

pp. e16751 ◽

Cited By ~ 1

Author(s):

Jing-Nan Hu ◽

Xiao-Feng Yang ◽

Chuan-Ming Li ◽

Xin-Xin Li ◽

Yun-Zhi Ding

Keyword(s):

Cortical Bone ◽

Pedicle Screw ◽

Lumbar Fusion ◽

Fusion Surgery ◽

Cortical Bone Trajectory ◽

Lumbar Fusion Surgery

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Systematic review of cortical bone trajectory versus pedicle screw techniques for lumbosacral spine fusion

Journal of Spine Surgery ◽

10.21037/jss.2017.11.03 ◽

2017 ◽

Vol 3 (4) ◽

pp. 679-688 ◽

Cited By ~ 11

Author(s):

Kevin Phan ◽

Vignesh Ramachandran ◽

Tommy M. Tran ◽

Kevin P. Shah ◽

Matthew Fadhil ◽

...

Keyword(s):

Systematic Review ◽

Cortical Bone ◽

Pedicle Screw ◽

Spine Fusion ◽

Lumbosacral Spine ◽

Cortical Bone Trajectory

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Clear Zone Formation around Screws in the Early Postoperative Stages after Posterior Lumbar Fusion Using the Cortical Bone Trajectory Technique

Asian Spine Journal ◽

10.4184/asj.2015.9.6.884 ◽

2015 ◽

Vol 9 (6) ◽

pp. 884 ◽

Cited By ~ 7

Author(s):

Koshi Ninomiya ◽

Koichi Iwatsuki ◽

Yu-Ichiro Ohnishi ◽

Toshika Ohkawa ◽

Toshiki Yoshimine

Keyword(s):

Cortical Bone ◽

Lumbar Fusion ◽

Clear Zone ◽

Zone Formation ◽

Cortical Bone Trajectory ◽

Posterior Lumbar Fusion

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Optimized Screw Trajectory for Lumbar Cortical Bone Trajectory Pedicle Screws Based on Clinical Outcome: Evidence Favoring the Buttress Effect Theory

Journal of Neurological Surgery Part A Central European Neurosurgery ◽

10.1055/s-0038-1641147 ◽

2018 ◽

Vol 79 (06) ◽

pp. 464-470 ◽

Cited By ~ 3

Author(s):

Shunji Asamoto ◽

Michael Winking ◽

Andreas Jödicke ◽

Masayuki Ishikawa ◽

Shinichi Ishihara ◽

...

Keyword(s):

Clinical Outcome ◽

Cortical Bone ◽

Pedicle Screw ◽

Lumbar Fusion ◽

Pedicle Screws ◽

Lateral View ◽

New Technique ◽

Cortical Bone Trajectory ◽

Translucent Zone ◽

Pars Interarticularis

Background Cortical bone trajectory (CBT) is a relatively new technique for pedicle screw insertion in the field of spine surgery. Previous studies have demonstrated the significantly better pullout and toggle characteristics the new method offers, and it appears to have certain advantages over the widely used traditional trajectory. The mechanism of the pullout and toggle characteristics still remains unknown. Purpose To report the medium- to long-term follow-up findings of patients who underwent posterior lumbar interbody fusion or posterior lumbar fusion (PLIF/PLF) at our institution and to discuss the ideal screw trajectory when using this technique. Study Design Retrospective radiologic study. Methods Fifty-five patients who underwent PLIF/PLF for lumbar spondylosis using the new technique between January 2011 and January 2016 were included. Clinical outcome was assessed using the Japanese Orthopaedic Association scores for low back pain and visual analog scale scores. Screw loosening was evaluated via the presence of a translucent zone surrounding the pedicle screw using plain X-radiography (Xp). The screw trajectory was evaluated by measuring the rostral range (RR) and the lateral range score (LRS). The RR is the angle between the line drawn along the distal end plate of the vertebra and the line drawn along the screw on the lateral view. The LRS is the score given depending on the position of the tip of the screw seen on the Xp taken in the anteroposterior (AP) view. The pedicle ring is equally divided into the medial third (zone A), central third (zone B), and the lateral third (zone C) by four vertical lines. A score of 0 to 3 points is given depending on the position of the tip of the screw: 0, outside the pedicle ring; 1, zone A; 2, zone B; and 3, zone C. Results Bone fusion was recorded in 49 patients (49/55 patients). The total number of screws with a visible translucent zone on Xp was 26 (26/242 screws). When the screws are inserted at a more acute angle in the lateral view (low RR) or when the screws are directed more medially (low LRS), the risk of developing a translucent zone around the pedicle screw increased. Conclusion With CBT, the pedicle screws are inserted from the pars interarticularis that is rich in cortical bone, strong enough to withstand the substantial forces usually encountered in the region. Our clinical data suggest that the optimal screw trajectory is one where the screw is inserted at an angle > 22.55 degrees (high RR) on the lateral view Xp and where the tip of the screw is directed toward the lateral third of the pedicle on the AP Xp. We believe the naturally occurring buttress effect that exists in the vertebra may give CBT a mechanical and anatomical advantage over the traditional screw trajectory.

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Comparison of facet joint violation in lumbar posterior spinal instrumentation using different techniques including cortical bone trajectory

Journal of Orthopaedics Trauma and Rehabilitation ◽

10.1177/2210491720903471 ◽

2020 ◽

Vol 27 (1) ◽

pp. 57-62

Author(s):

CY To ◽

P Cheung ◽

W Ng ◽

WY Mok

Keyword(s):

Cortical Bone ◽

Pedicle Screw ◽

Facet Joint ◽

Spinal Instrumentation ◽

Entry Site ◽

Cortical Bone Trajectory ◽

Percutaneous Pedicle Screw ◽

Iatrogenic Damage ◽

Percutaneous Screws ◽

Facet Joint Violation

Study background: A retrospective study to compare the rate of facet joint violation (FJV) in lumbar posterior spinal instrumentation using open pedicle screw, percutaneous pedicle screw, and cortical bone trajectory (CBT) technique. CBT is a new posterior spinal instrumentation technique in which a more caudal entry point can minimize iatrogenic damage to the cranial facet joint. Only one recent study reports incidence of FJV of 11%; however, no previous reports comment on radiological outcomes comparing to traditional open and percutaneous screws. Methods: We reviewed 90 patients who underwent lumbar posterior spinal instrumentation from January 2016 to June 2017. Postoperative computer tomography scans were performed to evaluate FJV. Incidence of FJV was graded by three reviewers according to Seo classification. Results: Totally, 446 screws (open 43.4%, percutaneous 37.8%, CBT 18.9%) were inserted. Among these, 6.3% (28/446) had screw head or rod in contact with facet joint and 0.9% (4/446) had screws directly invaded the facet joint. Overall, FJV was 7.2% (CTB = 3.4%, open = 10.4%, and percutaneous = 4.5%, p = 0.075). Conclusion: CBT technique has potential advantage in reducing FJV. It has a unique entry site at lateral aspect of pars interarticular with a caudomedial to craniolateral pathway. It is a reasonable alternative to open or percutaneous techniques in lumbar posterior spinal instrumentation.

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