Three-dimensional morphometric analysis of cervical vertebral endplate anatomy: A systematic literature review

•Literature on three-dimensional cervical endplate morphology is limited.•Existing studies differ in how they measure and define the same anatomical parameters.•Current cervical interbody devices do not reflect actual cervical anatomy.•Further anatomical data can potentially enhance designs of cervical interbody devices. Cervical fusion and arthroplasty are common surgical procedures where devices are inserted into cervical interbody spaces. These spaces are defined superiorly and inferiorly by adjacent vertebral body endplates. Having sufficient data on cervical endplate shape and size contributes to superior device designs associated with better functional outcomes and less postoperative complications. This study presents a systematic review of current literature on cervical endplate morphology and variation with age, gender and spinal level. A systematic review was conducted on 4 electronic databases using combinations of search terms (“endplate”, “cervical”, “cervical spine”, “morphology” and “anatomy”). Relevant articles (n = 10) were selected with additional studies identified through their citations (n = 2). Current literature on cervical endplate morphology is limited. Most studies reported that cervical endplate diameters and surface area (SA) increased with descending vertebral level. Only two studies investigated the relationship between age and cervical endplate diameters, with conflicting results. Females generally had smaller cervical endplate diameters and inferior vertebral endplates were more concave than superior counterparts. Relationships between gender, age and cervical endplate SA, concavity and concavity apex location were not well reported. Literature on three-dimensional (3D) cervical endplate and interbody space morphology is limited. Existing studies are based on linear and area parameters measured from two-dimensional (2D) imaging modalities (computed tomography (CT) and X-rays) in specific planes or 3D reconstructions of scanned spines (living or cadaveric). These 2D parameters do not capture the 3D shape of cervical endplates and studies differ on how they define these parameters, making data difficult to compare. Further studies utilising methods that better capture the 3D shape of cervical endplates would benefit our understanding of vertebral endplates and, thereby, cervical interbody space shape. In turn, greater morphological knowledge of cervical interbody spaces could aid in the design of new generation devices.