SPINE Volume 32, Number 14, pp E376 –E381 ©2007, Lippincott Williams & Wilkins, Inc. Quantitative Anatomy of the Endplate of the Middle and Lower Cervical Vertebrae in Koreans Moon-Kyu Kim, MD,* Dai-Soon Kwak, PhD,† Chun-Kun Park, MD, PhD,‡ Se-Hyuck Park, MD, PhD,* Sae-Moon Oh, MD, PhD,* Sang-Won Lee, MD, PhD,‡ and Seung-Ho Han, MD, PhD† Study Design. Assessment of the size and shape of cervical vertebral endplates in Koreans. Objective. To obtain data regarding cervical verte- brae and propose an appropriate size for artificial discs in Koreans. Summary of Background Data. The use of various types of cervical artificial discs has increased in recent years; hence, it is important to develop endplate implants of appropriate size. In this study, we determined the quantitative anatomy of cervical endplates in Koreans and proposed a new angular parameter. Methods. This study details the quantitative surface anatomy of the middle and lower cervical vertebral endplates based on the study of 272 cervical vertebrae in Korean cadavers. Computed tomographic images were obtained from 57 Korean cadavers (28 males and 29 females). The mean age and height were 51.14 years (range, 21– 60 years) and 161 cm (range, 146 –175 cm), respectively. The images were reconstructed, and lin- ear parameters (EPWu, upper endplate width; EPDu, upper endplate depth; EPWl, lower endplate width; and EPDl, lower endplate depth) and an angular parameter (AUA, anterior wall to uncovertebral joint angle) were measured. Results. The width and depth of both the upper and lower endplates increased from C3 through C7. The EPDu, EPWl, and EPDl values of Koreans were similar to those reported in whites, while the EPWu value in this study were smaller than those reported in whites. The AUA for C4 differed significantly between the sexes. The linear parameter values obtained using Korean cadavers were compared with those obtained using white and Singa- porean subjects. The EPWu values of Koreans were smaller than those reported in whites, while the values for all the parameters were considerably larger than those reported in Singaporeans. The AUA indicated the exis- tence of various relationships between the endplate and the uncovertebral joint. Conclusions. This data can be used to develop cervical devices for Koreans. The AUA should be studied in other populations. Key words: Koreans, cervical vertebra, anatomy, end- plate. Spine 2007;32:E376 –E381 The use of nonfusion devices such as various types of artificial cervical discs for preserving the segment motion and preventing adjacent segment disease has increased in recent years. 1–3 It is important that the implants used for these purposes are appropriately sized and positioned. Therefore, to prevent the subsidence and the inappropri- ate positioning of the implants, obtaining accurate quan- titative endplate data is a prerequisite for their develop- ment and for the instrumentation of artificial disc system. 4,5 However, there have been a few available reports of accurate quantitative anatomic data with regard to the cervical endplate. 6,7 There have been also been reports regarding the anatomy of cervical vertebrae; however, most of these studies used simplistic measurement tech- niques. 8,9 –13 Further, Panjabi et al 6 and Tan et al 7 re- ported regarding the anteroposterior diameter and width of the cervical vertebral body without considering the variations in the shape of the cervical endplate. More- over, no study has investigated the quantitative anatomy of the cervical endplate in Koreans. Therefore, this study was undertaken to determine the quantitative anatomy of the cervical endplate in Koreans. Further, we also pro- posed an additional parameter for this determination. Materials and Methods This study details the quantitative surface anatomy of the middle and lower cervical vertebral endplates; this informa- tion is based on the study of 272 cervical vertebrae of Korean cadavers (13 vertebrae were excluded due to focal spondy- losis). Computed tomography (CT) was carried out on the C3–C7 vertebrae in 57 Korean cadavers (28 males and 29 females) without any destructive procedure. The CT images were obtained by using a slice thickness of 1 mm. The ca- davers were identified on the basis of age, sex, and height. The mean age of the subjects was 51.14 years (range, 21– 60 years) and the mean height, 161 cm (range, 146 –175 cm). The images were reconstructed to 3-dimensional structures by using the Bionix Body Builder software Ver3.3 (Cantibio, Suwon, Korea) and adjusting the 3-dimensional coordinates. The poste- rior wall was used as a reference plane as described by Panjabi et al (Figure 1). 14 Linear parameters (EPWu, upper endplate width; EPDu, upper endplate depth; EPWl, lower endplate From the *Department of Neurosurgery, Kangdong Sacred Heart Hospital, Hallym University College of Medicine; †Department of Anatomy, Catholic Institute for Applied Anatomy, College of Med- icine, Catholic University of Korea; and ‡Department of Neurosur- gery, Kangnam St. Mary’s Hospital, College of Medicine, Catholic University of Korea, Seoul, Korea. Acknowledgment date: December 6, 2006. First revision date: February 7, 2007. Acceptance date: February 9, 2007. The manuscript submitted does not contain information about medical device(s)/drug(s). Federal funds were received in support of this work. No benefits in any form have been or will be received from a commercial party related directly or indirectly to the subject of this manuscript. Address correspondence and reprint requests to Seung-Ho Han, MD, PhD, Department of Anatomy, Catholic Institute for Applied Anatomy, College of Medicine, Catholic University of Korea, 505 Banpo-Dong, Seocho-Ku, Seoul, Korea; E-mail: hsh@catholic.ac.kr E376