Morphometry evaluations of cervical osseous endplates based on three dimensional reconstructions.

PURPOSE

Accurate and comprehensive data on cervical endplates is essential for developing and improving cervical devices. However, current literature on vertebral disc geometry is scarce or not suitable. The aim of this study was to obtain quantitative parameters of cervical endplates and provide morphometric references for designing cervical devices.

METHODS

In this study, 19 human cervical spine cadaveric specimens were considered. Employing a reverse engineering system, the surface information of each endplate was recorded in digital cloud and then 3D reconstructed. A measurement protocol that included three sagittal and three frontal surface curves was developed. The information of surface curves and endplate concavity were obtained and analyzed. The parametric equations of endplate surfaces were deduced based on coordinates of landmarks, and the reliability was verified.

RESULTS

The cervical endplate surface had a trend that to be transversely elongated gradually. The concavity depths of inferior endplates (1.88 to 2.13 mm) were significantly larger than those of superior endplates (0.62 to 0.84 mm). The most-concave points in inferior endplates were concentrated in the central portion, while always located in post-median region in superior endplates.

CONCLUSION

These results will give appropriate guidelines to design cervical prostheses without sacrificing valuable bone stock. The parametric equations applied for generating surface profile of cervical endplates may provide great convenience for subsequent studies.