Cortical Trajectory Pedicle Screws for the Fixation of Traumatic Thoracolumbar Fractures

Abstract

ObjectiveCortical bone trajectory pedicle screws (CBT) have a different trajectory compared to traditional pedicle screws (PS) and they may confer biomechanical advantages in some patient populations. We hypothesize that the placement of CBT in traumatic thoracolumbar fractures could be an alternative technique to the traditional utilization of PS.MethodsSingle surgeon, retrospective study was performed at a Level 1 Trauma Center from 2013 to 2017. All patients aged between 18 and 90 years with operative AO classification A, B, and C traumatic thoracolumbar fractures were included. Patients with pathological fractures, active spinal infections, or history of vertebral augmentation were excluded. Age, injury severity score (ISS), AO classification, operative time, estimated blood loss (EBL), length of stay (LOS), and presence of proximal junctional kyphosis (PJK) or construct failure were compared between CBT and PS groups. The PS group was further separated into open reduction internal fixation (ORIF) and minimally invasive spine (MIS) groups. All CBT and ORIF cases were completed via open incisions allowing arthrodesis of the involved lamina and facet joints whereas no arthrodesis was completed in the MIS patients. Choice of technique was at the attending surgeon’s discretion.ResultsThe study included 71 patients, out of which 12 received CBT and 59 received PS. Of the 59 PS patients, 39 were ORIF and 20 were MIS. The average operative time was 22.9 minutes less in CBT compared to ORIF (p = 0.24). EBL was 337.50 mL for CBT, 184.33 mL for MIS, and 503.33 mL for ORIF (p = 0.01) demonstrating that MIS technique results in a significantly reduced blood loss. However, EBL was comparable for CBT versus MIS (p > 0.05). ISS was not significantly different between the three groups (p = 0.89). LOS was 4.06 days fewer for CBT patients compared to ORIF patients (p = 0.36). There was one case of construct failure as well as one case of incisional site infection in the PS group, but none were found in the CBT group. Instances of PJK complications were determined by the change in the Cobb angle over time and they were not statistically different between the three groups (p = 0.68).ConclusionsCBT is noninferior to PS in the fixation of unstable adult traumatic thoracolumbar fractures. With the exception of EBL, CBT was not statistically different compared to MIS and ORIF. This study establishes a precedent to expand the application of this new technique and investigate with larger sample sizes.

Accuracy and safety of robot-assisted cortical bone trajectory screw placement: a comparison of robot-assisted technique with fluoroscopy-assisted approach

“…Compared to conventional techniques, CBT increases screw purchase while reducing surgical trauma. Therefore, the CBT technique is considered appropriate for cases of severe obesity, osteoporosis, and those requiring revision of conventional pedicle screws [ 3 ].…”

Complication, fusion, and revision rate in the lumbar cortical bone trajectory and pedicle screw fixation techniques: a systematic review and meta-analysis

“…According to the inclusion and exclusion criteria, 29 studies [ 13 – 41 ] met the inclusion criteria, 22 in English and 6 in Chinese. Two RCTs [ 32 , 34 ], six prospective studies [ 13 , 14 , 20 , 27 , 35 , 36 ], and 21 retrospective studies [ 15 – 19 , 21 – 26 , 28 – 31 , 33 , 37 , 38 , 40 , 41 ] were included. A total of 982 patients with CBT and 1105 patients with PS were compared.…”

“…A total of 982 patients with CBT and 1105 patients with PS were compared. One retrospective cohort study [ 38 ] did not report the specific follow-up time, but the hardware complication (intraoperative screw malposition) did not require long-term follow-up;thus, it was included. Among the included studies, Lai et al [ 26 ] included patients with lumbar tuberculosis and the rest research only included patients with lumbar degenerative diseases.…”

“…Nineteen studies [ 13 , 16 , 17 , 19 – 23 , 27 , 28 , 30 – 34 , 37 , 38 , 40 , 41 ] (consistent with the hardware complications of CBT) consisting of 773 patients reported the hardware complications of PS ( n = 29). There was a significant heterogeneity ( I 2 = 60%, P < 0.01).…”

Advantages of Short-Segment Fusion in the Surgical Management of Thoracolumbar Traumatic Fractures: A Case Series and Review of the Literature

“…Additionally, selective placement of screws at the fracture level can aid in alignment and increase construct strength [ 24 ]. When considering the location of screw placement itself, cortical screws have been proven equivalent to pedicle screws in terms of fixation strength [ 25 ]. However, bone quality and other individual patient factors should be considered when evaluating the choice of screw trajectory.…”