Prediction of Cervical Endplate Size: One Size Does Not Fit All

Abstract

Significant variations exist in the footprint size of cervical vertebral endplates. In anterior cervical spine surgery, an implant that maximizes coverage of the endplate and contacts the apophyses may reduce subsidence and decrease risk of endplate fracture. The ability to accurately predict a patient's vertebral endplate size may be helpful for surgeons to preoperatively choose the optimal implant for the patient's specific anatomy. The purpose of this study was to (1) demonstrate the range of vertebral endplate sizes between individual patients and cervical levels and (2) determine if vertebral endplate size can be predicted based on patient characteristics and vertebral level. Fifty cervical computed tomography scans of patients 18 to 65 years old were selected for analysis. Superior vertebral endplate sizes of C3-C7 were measured medial-laterally and anteriorly-posteriorly. The medial-laterally measurement was taken from the midbody coronal view at the flat central region of the superior endplate, and the anteriorly-posteriorly measurement was taken at the midbody axial view from the front to back edge of the vertebral body. Age, height, weight, gender, and race were recorded for all patients. One-way analysis of variance, linear regressions, and multivariate regressions were performed. Patient height, age, gender, and race accounted for 51% to 71% of the variance between individuals, and endplate size increased by 1 mm in width and 0.6 mm in depth for each progressively more caudal vertebral level. Vertebral endplate size could be reliably calculated based on patient height, age, gender, and vertebral level. These data may be useful to assist surgeons in preoperative planning for patient-specific implant selection. [Orthopedics. 2016; 39(3):e526-e531.].