PMID- 36868381 OWN - NLM STAT- MEDLINE DCOM- 20230626 LR - 20240123 IS - 1878-1632 (Electronic) IS - 1529-9430 (Linking) VI - 23 IP - 7 DP - 2023 Jul TI - The association between unilateral high-riding vertebral artery and atlantoaxial joint morphology: a multi-slice spiral computed tomography study of 396 patients and a finite element analysis. PG - 1054-1067 LID - S1529-9430(23)00095-5 [pii] LID - 10.1016/j.spinee.2023.02.017 [doi] AB - BACKGROUND CONTEXT: A high-riding vertebral artery (HRVA) can deviate too medially, too posteriorly, or too superiorly to allow the safe insertion of screws. However, it is unknown whether the presence of a HRVA is associated with morphological changes of the atlantoaxial joint. PURPOSE: To investigate the association between HRVA and atlantoaxial joint morphology in patients with and without HRVA. STUDY DESIGN: A retrospective case-control study and finite element (FE) analysis. PATIENT SAMPLE: A total of 396 patients with cervical spondylosis underwent multi-slice spiral computed tomography (MSCT) of cervical spine at our institutions from 2020 to 2022. OUTCOME MEASURES: A series of atlantoaxial joint morphological parameters, including C2 lateral mass settlement (C2 LMS), C1-2 sagittal joint inclination (C1-2 SI), C1-2 coronal joint inclination (C1-2 CI), atlanto-dental interval (ADI), lateral atlanto-dental interval (LADI), and C1-2 relative rotation angle (C1-2 RRA) were measured, and lateral atlantoaxial joints osteoarthritis (LAJs-OA) was recorded. The stress distribution on the C2 facet surface under different torques of flexion-extension, lateral bending, and axial rotation was analyzed by FE models. A 2-Nm moment was applied to all models to determine the range of motion (ROM). METHODS: A total of 132 consecutive cervical spondylosis patients with unilateral HRVA were enrolled in the HRVA group, and 264 patients without HRVA matched for age and sex were enrolled in the normal (NL) group. Atlantoaxial joint morphological parameters were compared between two sides of C2 lateral mass within HRVA or NL group, and between HRVA and NL groups. A 48-year-old woman with cervical spondylosis without HRVA was selected for cervical MSCT. A three-dimensional (3D) FE intact model of the normal upper cervical spine (C0-C2) was created. We established the HRVA model by simulating atlantoaxial morphological changes of unilateral HRVA with FE method. RESULTS: The C2 LMS was significantly smaller on the HRVA side than that on the non-HRVA side in the HRVA group, but C1-2 SI, C1-2 CI, and LADI on HRVA side were significantly larger than those on non-HRVA side. There was no significant difference between left and right sides in the NL group. The difference in C2 LMS (d-C2 LMS) between HRVA side and non-HRVA side in the HRVA group was larger than that in the NL group (P < 0.05). Meanwhile, the differences in C1-2 SI (d-C1/2 SI), C1-2 CI (d-C1/2 CI), and LADI (d-LADI) in the HRVA group were significantly larger than those in the NL group. The C1-2 RRA in the HRVA group was significantly larger than that in the NL group. Pearson correlations showed that d-C1/2 SI, d-C1/2 CI, and d-LADI were positively associated with d-C2 LMS (r=0.428, 0.649, 0.498, respectively, p<.05 for all). The incidence of LAJs-OA in the HRVA group (27.3%) was significantly larger than that in the NL group (11.7%). Compared with the normal model, the ROM of C1-2 segment declined in all postures of the HRVA FE model. We found a larger distribution of stress on the C2 lateral mass surface of the HRVA side under different moment conditions. CONCLUSIONS: We suggest that HRVA affects the integrity of the C2 lateral mass. This change in patients with unilateral HRVA is associated with the nonuniform settlement of the lateral mass and an increase in the lateral mass inclination, which may further affect the degeneration of the atlantoaxial joint because of the stress concentration on the C2 lateral mass surface. CI - Copyright (c) 2023 Elsevier Inc. All rights reserved. FAU - Tang, Chao AU - Tang C AD - Department of Orthopedics, Xinqiao Hospital, Army Medical University (Third Military Medical University), Chongqing city, China; Department of Orthopedics, Affiliated Hospital of Southwest Medical University, Luzhou city, Sichuan province, China. FAU - Liao, Ye Hui AU - Liao YH AD - Department of Orthopedics, Affiliated Hospital of Southwest Medical University, Luzhou city, Sichuan province, China. FAU - Wang, Qing AU - Wang Q AD - Department of Orthopedics, Affiliated Hospital of Southwest Medical University, Luzhou city, Sichuan province, China. FAU - Tang, Qiang AU - Tang Q AD - Department of Orthopedics, Affiliated Hospital of Southwest Medical University, Luzhou city, Sichuan province, China. FAU - Ma, Fei AU - Ma F AD - Department of Orthopedics, Affiliated Hospital of Southwest Medical University, Luzhou city, Sichuan province, China. FAU - Cai, Chen Hui AU - Cai CH AD - Department of Orthopedics, Xinqiao Hospital, Army Medical University (Third Military Medical University), Chongqing city, China. FAU - Xu, Shi Cai AU - Xu SC AD - Department of Orthopedics, Affiliated Hospital of Southwest Medical University, Luzhou city, Sichuan province, China. FAU - Leng, Ye Bo AU - Leng YB AD - Department of Orthopedics, Affiliated Hospital of Southwest Medical University, Luzhou city, Sichuan province, China. FAU - Chu, Tong Wei AU - Chu TW AD - Department of Orthopedics, Xinqiao Hospital, Army Medical University (Third Military Medical University), Chongqing city, China. Electronic address: chtw@sina.com. FAU - Zhong, De Jun AU - Zhong J AD - Department of Orthopedics, Affiliated Hospital of Southwest Medical University, Luzhou city, Sichuan province, China. Electronic address: zdj_spine802@swmu.edu.cn. LA - eng PT - Case Reports PT - Journal Article DEP - 20230301 PL - United States TA - Spine J JT - The spine journal : official journal of the North American Spine Society JID - 101130732 SB - IM MH - Female MH - Humans MH - Middle Aged MH - *Atlanto-Axial Joint/diagnostic imaging/surgery MH - Finite Element Analysis MH - Vertebral Artery/diagnostic imaging MH - Retrospective Studies MH - Case-Control Studies MH - *Spinal Fusion/methods MH - Biomechanical Phenomena MH - Cervical Vertebrae/diagnostic imaging/surgery MH - Tomography, Spiral Computed MH - Range of Motion, Articular MH - *Spondylosis/diagnostic imaging/surgery OTO - NOTNLM OT - Atlantoaxial joint morphology OT - C2 lateral mass OT - Finite element analysis OT - High-riding vertebral artery OT - Imaging anatomic study OT - Nonuniform settlement COIS- Competing interest statement The authors have no competing interests to declare. EDAT- 2023/03/04 06:00 MHDA- 2023/06/26 06:41 CRDT- 2023/03/03 19:28 PHST- 2022/11/14 00:00 [received] PHST- 2023/02/14 00:00 [revised] PHST- 2023/02/23 00:00 [accepted] PHST- 2023/06/26 06:41 [medline] PHST- 2023/03/04 06:00 [pubmed] PHST- 2023/03/03 19:28 [entrez] AID - S1529-9430(23)00095-5 [pii] AID - 10.1016/j.spinee.2023.02.017 [doi] PST - ppublish SO - Spine J. 2023 Jul;23(7):1054-1067. doi: 10.1016/j.spinee.2023.02.017. Epub 2023 Mar 1.