3D-printed navigation template in cervical spine fusion: a systematic review and meta-analysis

To explore the effectiveness and advantage of three-dimensional (3D)-printed navigation templates (3DPN-template) assisted in cervical spine fusion (CSF) surgery as compared to conventional surgery.

An electronic literature search in PubMed, Scopus, Web of Science, and Cochrane was conducted for studies of 3DPN-templates in CSF up to May 2020. Outcome measures as the accuracy rate, operation time, intra-operative blood loss, and fluoroscopy used, associated with CSF were extracted. Mean difference based on changes was quantified using Hedges' g.

From 4414 potentially relevant studies, 61 full-text publications were screened. Thirteen studies comprising 330 cases with 1323 screw placements were eligible for inclusion. For template group, pooled estimates were as follows: 97.3% accuracy rate for screw placement, 144.7 min for operating time, 273.6 ml for blood loss, and 3.2 min for fluoroscopic times. A significantly positive difference was observed between the template group compared to control group in terms of accuracy rate of screw placement (Z = 5.3), operation time (Z = 2.41), intra-operative blood loss (Z = 2.64), and fluoroscopic times (Z = 3.64) (all, P value < 0.0001). Risk of bias for studies under review was assessed using the Newcastle-Ottawa Scale (NOS), and 11 studies were found as having high quality. Overall, funnel plot and Begg's test did not indicate obvious publication bias.

The 3D-printed navigation template in the cervical surgery can improve accuracy of pedicle screw placement and consequently improve outcomes. In future, multi-center efforts are needed to validate the relationships found in this review.