Outcomes after Cortical Bone Trajectory Screw versus Traditional Pedicle Screw in Single-Level Lumbar Spine Surgery: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

Background: Cortical bone trajectory screw (CBTS) is reported to offer increased cortical bone purchase and improved outcomes as compared to the traditional pedicle screw (PS), particularly in osteoporotic patients. The systematic review aims to compare randomized controlled trials comparing CBTS with PS in single-level lumbar spine fusion surgery.

Methods: A systematic search was conducted on PubMed (MEDLINE), Scopus, Embase, Web of Science, and Cochrane. Moreover, ClinicalTrials.gov, International Clinical Trials Registry Platform (ICTRP), and China National Knowledge Infrastructure (CNKI) were also searched. Outcome measures included fusion rates, complication rates, perioperative parameters, pain scores, and functionality. (PROSPERO: CRD42024523809).

Results: Four manuscripts, reporting on three randomized controlled trials (RCTs) and 416 patients, were included in this review. The follow-up ranged from 24 to 26 months postoperatively. All patients underwent single-level fusion only. There was no significant difference in the fusion rates between CBTS and PS at one-year (risk ratio [RR] 1.05 [0.97, 1.13], p=0.24) or two-year (RR 1.02 [0.96, 1.08], p=0.47) follow-ups. The CBTS group had a lower risk of intraoperative complications (RR 0.44 [0.32, 0.60], p<0.001) but an equal risk of postoperative complications (RR 0.71 [0.42, 1.22], p=0.22). There was no difference in pain, functionality, disability, and quality-of-life scores. CBTS group had better outcomes in incision length (mean difference [MD] -25.44 [-40.76, -10.12], p=0.001), operative time (MD -20.71 [-32.91, -8.51], p=0.009), and blood loss (MD -60.23 [-106.74, -13.72], p=0.01), while there was no difference in length of stay (MD -0.49 [-1.01, 0.04], p=0.07).

Conclusions: Although slightly favoring CBTS, RCTs were limited in number and had a serious risk of bias. Future RCTs should use superiority trial designs, have minimal bias, and include implant details, incidence of adjacent segment disease, and quality-of-life metrics.