Misaligned Versus Straight Placement of Anterior Cervical Plates

Kingsley R. Chin, Fabio J.R. Pencle, Shannon D. Francis, Chloe A. Francis, Jason A. Seale, Elijah A. Hothem

In anterior cervical diskectomy and fusion (ACDF), misaligned plates are concerning because of the risk of screw-and-plate failure; however, these plates also hypothetically have the potential for asymmetric micromotion on the facet and uncovertebral joint. The aim of this study was to determine whether misaligned plate placement during ACDF had clinical benefits compared with straight plate placement. Postoperative AP radiographs of 128 consecutive patients who underwent ACDF with anterior cervical plate (ACP) fixation were reviewed, and plate alignment was assessed. Patients were separated into control group 1 (straight plates) or group 2 (misaligned plates). The mean age of patients was 51.5 ± 0.9 years, and women represented 51% of the total population. There was no significant difference between groups with regard to the preoperative visual analog scale (VAS) and Neck Disability Index (NDI) scores (P = 0.744 and P = 0.943, respectively). At 6 weeks postoperatively, the VAS scores for group 1 decreased from 7.6 ± 0.2 to 4.0 ± 0.2 compared with the scores in group 2, which decreased from 7.7 ± 0.2 to 2.1 ± 0.1, which demonstrated statistical significance (P = 0.019). At 2-year follow-up, no significant difference was demonstrated between the groups' VAS and NDI scores (P = 0.670 and P = 0.266). Misaligned plates have increased torsional strength and are associated with better clinical outcomes compared with those of straight plates in the early postoperative period. After fusion, no significant difference in clinical outcomes between the groups was noted, which may reduce the concerns regarding misaligned plates. Retrospective comparative study.