The use of the cortical bone trajectory (CBT) technique has not only shown similar intra-pedicular accuracy compared to traditional trajectory (TT) but also “remarkable superiority” in terms of proximal facet joint protection in transforaminal lumbar interbody fusion (TLIF) patients, new research suggests.
The retrospective study, published in the journal Spine by Cai-Lang Shen (First Affiliated Hospital of Anhui Medical University, Hefei, China) et al, compared the accuracy of pedicle screw placement and proximal facet joint violation (FJV) in single-level degenerative lumbar diseases using CBT and TT techniques, and analysed their possible risk factors.
A total of 40 patients who required single-level instruments were included in the study and were treated with the CBT-TLIF and the TT-TLIF techniques (1:1 ratio) from March 2019 to August 2020. The radiographic outcomes were the intra-pedicular accuracy and proximal FJV. In addition, the possible risk factors were assessed using bivariate and multivariate analyses.
In regards to intra-pedicular accuracy, 73 screws (91.3%) were classified as grade A and seven screws (8.7%) classified as grade B in the CBT group. A total of 71 screws (88.8%) were graded A with eight screws (10%) graded B and one screw (1.2%) graded C in the TT group. The proportion of optimal and clinically acceptable screw positions in the two groups were not significantly different (p>0.05). In addition, the rate of proximal FJV in the CBT approach (8.3%) was significantly lower than that in the TT approach (35%) (p<0.001).
Multivariate analysis showed that the TT insertion approach and a facet angle of ≥45° were the independent risk factors for proximal FJV, but none of these factors affected intra-pedicular accuracy.