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Song X, Yu SB, Yuan XY, Alam Shah MA, Li C, Chi YY, Zheng N, Sui HJ. Evidence for chronic headaches induced by pathological changes of myodural bridge complex. Sci Rep 2024; 14:5285. [PMID: 38438423 PMCID: PMC10912660 DOI: 10.1038/s41598-024-55069-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2023] [Accepted: 02/20/2024] [Indexed: 03/06/2024] Open
Abstract
Clinical studies have shown that there may be a certain relationship between pathological changes of the myodural bridge complex (MDBC) and chronic headaches of unknown cause. But there is still a lack of experimental evidence to explain the possible mechanism. This study aims to further confirm this relationship between MDBC and chronic headaches and explore its potential occurrence mechanism in rats. Bleomycin (BLM) or phosphate-buffered saline (PBS) was injected into the myodural bridge fibers of rats to establish the hyperplastic model of MDBC. After 4 weeks, the occurrence of headaches in rats was evaluated through behavioral scores. The immunohistochemistry staining method was applied to observe the expression levels of headache-related neurotransmitters in the brain. Masson trichrome staining results showed that the number of collagen fibers of MDBC was increased in the BLM group compared to those of the other two groups. It revealed hyperplastic changes of MDBC. The behavioral scores of the BLM group were significantly higher than those of the PBS group and the blank control group. Meanwhile, expression levels of CGRP and 5-HT in the headache-related nuclei of the brain were increased in the BLM group. The current study further confirms the view that there is a relationship between pathological changes of MDBC and chronic headaches of unknown cause. This study may provide anatomical and physiological explanations for the pathogenesis of some chronic headaches of unknown cause.
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Affiliation(s)
- Xue Song
- Department of Anatomy, College of Basic Medicine, Dalian Medical University, Dalian, 116044, China
| | - Sheng-Bo Yu
- Department of Anatomy, College of Basic Medicine, Dalian Medical University, Dalian, 116044, China
| | - Xiao-Ying Yuan
- Department of Anatomy, College of Basic Medicine, Dalian Medical University, Dalian, 116044, China
| | - M Adeel Alam Shah
- Department of Anatomy, College of Basic Medicine, Dalian Medical University, Dalian, 116044, China
| | - Chan Li
- Department of Anatomy, College of Basic Medicine, Dalian Medical University, Dalian, 116044, China
| | - Yan-Yan Chi
- Department of Anatomy, College of Basic Medicine, Dalian Medical University, Dalian, 116044, China
| | - Nan Zheng
- Department of Anatomy, College of Basic Medicine, Dalian Medical University, Dalian, 116044, China.
| | - Hong-Jin Sui
- Department of Anatomy, College of Basic Medicine, Dalian Medical University, Dalian, 116044, China.
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Murakami G, Cho KH, Kitamura K, Rodríguez-Vázquez JF, Sato T. Rectus capitis lateralis muscle revisited: a histological study using human fetuses. Surg Radiol Anat 2023; 45:1483-1491. [PMID: 37658911 DOI: 10.1007/s00276-023-03237-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Accepted: 08/23/2023] [Indexed: 09/05/2023]
Abstract
BACKGROUND Rectus capitis lateralis muscle (RCLM) is located at the border between the ventral and dorsal muscle groups, but the nerve topographical anatomy around the muscle is obscure. MATERIALS AND METHODS We observed the RCLM in histological sections of 12 midterm and 10 near-term fetal heads (9-18 and 26-40 weeks of gestational age). RESULTS At midterm, the RCLM wrapped around the inferiorly protruding inferolateral corner of the cartilaginous occipital bone. The muscle was adjacent to, or even continued to, the intertransversarius muscle between the atlas and axis. At near-term, the jugular process of the occipital bone, that is, the RCLM upper insertion, was either cartilaginous or bony, depending on age. The process formed a collar supporting the internal jugular vein from the inferior side. Moreover, the muscle is tightly attached to or inserted into the venous wall itself. The cartilaginous jugular process was adjacent to Reichert's cartilage, and the uppermost muscle fibers passed through a narrow space between these cartilages. The RCLM appeared to accelerate the jugular process elongation, resulting in complete union of the occipital and temporal bones. The ventral ramus of the first cervical nerve passed between the RCLM and rectus capitis anterior muscle to reach the longus capitis muscle. No nerve passed between the RCLM and the obliquus capitis superior muscle (a muscle at the suboccipital triangle). CONCLUSION The dorsoventral position of the RCLM seemed to correspond to the scalenus posterior muscle in a laminar arrangement of the cervical axial musculature.
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Affiliation(s)
- Gen Murakami
- Division of Internal Medicine, Cupid Clinic, Iwamizawa, Japan
| | - Kwang Ho Cho
- Department of Neurology, Institute of Wonkwang Medical Science, Wonkwang University School of Medicine and Hospital, 895, Muwang-ro, Iksan-si, Jeollabuk-do, 54538, Republic of Korea.
| | - Kei Kitamura
- Department of Histology and Embryology, Tokyo Dental College, Tokyo, Japan
- Department of Anatomy and Embryology, School of Medicine, Complutense University, Madrid, Spain
| | | | - Tatsuo Sato
- Emeritus Professor of Tokyo Medical and Dental University, Tokyo, Japan
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Song Y, Lai HX, Song TW, Gong J, Liu B, Chi YY, Yue C, Zhang J, Sun SZ, Zhang CH, Tang W, Fan N, Yu WH, Wang YF, Hack GD, Yu SB, Zhang JF, Sui HJ. The growth and developmental of the myodural bridge and its associated structures in the human fetus. Sci Rep 2023; 13:13421. [PMID: 37591924 PMCID: PMC10435443 DOI: 10.1038/s41598-023-40709-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Accepted: 08/16/2023] [Indexed: 08/19/2023] Open
Abstract
Myodural bridge (MDB) is a dense connective tissue between suboccipital muscle and dura mater. However, there are few reports on the development and maturation of the human MDB. This study aims to explore the developmental relationship between suboccipital muscle and MDB. 30 head and neck specimens from human fetuses (F) ranging from the 12th to 41st week (W) were made into histological sections. The F12W sections showed evidence that the dura mater dominated by fibroblasts, attached to the posterior atlanto-axial membrane (PAAM) which completely sealed the atlanto-axial space. In the F13W stage, myofibrils of the suboccipital muscle fibers increased significantly in number. At the F14W stage, a gap was observed at the caudal end of the PAAM. Numerous myodural bridge-like structures were observed blending into the dura mater through the gap. At the F19W stage, muscle cells mature. Starting at the F21W stage, the MDB were observed as fibroblasts that cross the atlanto-axial interspace and attach to the dura mater. Therefore, the traction generated by the suboccipital muscles seems to promote the maturity of MDB. This study will provide new morphological knowledge to support future research on the function of the human MDB and regulating the development mechanism of MDB.
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Affiliation(s)
- Yang Song
- Department of Anatomy, College of Basic Medicine, Dalian Medical University, Dalian, 116044, Liaoning, China
| | - Hua-Xun Lai
- Department of Anatomy, College of Basic Medicine, Dalian Medical University, Dalian, 116044, Liaoning, China
| | - Ting-Wei Song
- Department of Anatomy, College of Basic Medicine, Dalian Medical University, Dalian, 116044, Liaoning, China
- Department of Neurology, Angang Group Company General Hospital, Anshan, 114000, Liaoning, China
| | - Jin Gong
- Department of Anatomy, College of Basic Medicine, Dalian Medical University, Dalian, 116044, Liaoning, China
| | - Bo Liu
- Department of Histology and Embryology, College of Basic Medicine, Dalian Medical University, Dalian, 116044, Liaoning, China
| | - Yan-Yan Chi
- Department of Anatomy, College of Basic Medicine, Dalian Medical University, Dalian, 116044, Liaoning, China
| | - Chen Yue
- Department of Anatomy, College of Basic Medicine, Dalian Medical University, Dalian, 116044, Liaoning, China
- Department of Obstetrics and Gynecology, Affiliated Zhongshan Hospital of Dalian University, Dalian, 116001, Liaoning, China
| | - Jing Zhang
- Department of Anatomy, College of Basic Medicine, Dalian Medical University, Dalian, 116044, Liaoning, China
| | - Shi-Zhu Sun
- Basic and Clinical Medicine Teaching Laboratory, School of Medicine, Sun-Yat-Sen-University, Guangdong, 518100, China
| | - Cheng-Hong Zhang
- Morphology Laboratory, College of Basic Medicine, Dalian Medical University, Dalian, 116044, Liaoning, China
| | - Wei Tang
- Department of Anatomy, College of Basic Medicine, Dalian Medical University, Dalian, 116044, Liaoning, China
| | - Ning Fan
- Department of Anatomy, College of Basic Medicine, Dalian Medical University, Dalian, 116044, Liaoning, China
| | - Wei-Hua Yu
- Department of Obstetrics and Gynecology, Lvshun District Hospital, Dalian, 116044, Liaoning, China
| | - Yi-Fei Wang
- Department of Obstetrics and Gynecology, Affiliated Zhongshan Hospital of Dalian University, Dalian, 116001, Liaoning, China
| | - Gary D Hack
- Department of Advanced Oral Sciences and Therapeutics, University of Maryland School of Dentistry, Baltimore, MD, 21201, USA
| | - Sheng-Bo Yu
- Department of Anatomy, College of Basic Medicine, Dalian Medical University, Dalian, 116044, Liaoning, China
| | - Jian-Fei Zhang
- Department of Anatomy, College of Basic Medicine, Dalian Medical University, Dalian, 116044, Liaoning, China.
| | - Hong-Jin Sui
- Department of Anatomy, College of Basic Medicine, Dalian Medical University, Dalian, 116044, Liaoning, China.
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Zhang XH, Gong J, Song Y, Hack GD, Jiang SM, Yu SB, Song X, Zhang J, Yang H, Cheng J, Sui HJ, Zheng N. An anatomical study of the suboccipital cavernous sinus and its relationship with the myodural bridge complex. Clin Anat 2023. [PMID: 37096831 DOI: 10.1002/ca.24048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Revised: 03/11/2023] [Accepted: 04/10/2023] [Indexed: 04/26/2023]
Abstract
The suboccipital cavernous sinus (SCS) and the myodural bridge complex (MDBC) are both located in the suboccipital region. The SCS is regarded as a route for venous intracranial outflow and is often encountered during surgery. The MDBC consists of the suboccipital muscles, nuchal ligament, and myodural bridge and could be a power source for cerebrospinal fluid circulation. Intracranial pressure depends on intracranial blood volume and the cerebrospinal fluid. Since the SCS and MDBC have similar anatomical locations and functions, the aim of the present study was to reveal the relationships between them and the detailed anatomical characteristics of the SCS. The study involved gross dissection, histological staining, P45 plastination, and three-dimensional visualization techniques. The SCS consists of many small venous sinuses enclosed within a thin fibrous membrane that is strengthened by a fibrous arch closing the vertebral artery groove. The venous vessels are more abundant in the lateral and medial portions of the SCS than the middle portion. The middle and medial portions of the SCS are covered by the MDBC. Type I collagen fibers arranged in parallel and originating from the MDBC terminate on the SCS either directly or indirectly via the fibrous arch. The morphological features of SCS revealed in this research could serve as an anatomical basis for upper neck surgical procedures. There are parallel arrangements of type I collagen fibers between the MDBC and the SCS. The MDBC could change the blood volume in the SCS by pulling its wall during the head movement.
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Affiliation(s)
- Xu-Hui Zhang
- Department of Anatomy, Dalian Medical University, Dalian, China
| | - Jin Gong
- Department of Anatomy, Dalian Medical University, Dalian, China
| | - Yang Song
- Department of Anatomy, Dalian Medical University, Dalian, China
| | - Gary D Hack
- Department of Advanced Oral Sciences and Therapeutics, University of Maryland School of dentistry, Baltimore, USA
| | - Si-Meng Jiang
- Postgraduate Training Base, The 967 Hospital of the Joint Logistics Support Force, Jinzhou Medical University, Dalian, China
| | - Sheng-Bo Yu
- Department of Anatomy, Dalian Medical University, Dalian, China
| | - Xue Song
- Department of Anatomy, Dalian Medical University, Dalian, China
| | - Jing Zhang
- Department of Anatomy, Dalian Medical University, Dalian, China
| | - Heng Yang
- Department of Anatomy, Dalian Medical University, Dalian, China
| | - Jing Cheng
- Department of Anatomy, Dalian Medical University, Dalian, China
| | - Hong-Jin Sui
- Department of Anatomy, Dalian Medical University, Dalian, China
- Dalian Hoffen Preservation Technique Institution, Dalian, China
| | - Nan Zheng
- Department of Anatomy, Dalian Medical University, Dalian, China
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Wang J, Li Y, Wang M, Yang S. Localization of the Center of the Intramuscular Nerve Dense Region of the Suboccipital Muscles: An Anatomical Study. Front Neurol 2022; 13:863446. [PMID: 35463128 PMCID: PMC9019081 DOI: 10.3389/fneur.2022.863446] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Accepted: 03/03/2022] [Indexed: 11/30/2022] Open
Abstract
Purpose This study aimed to determine the body surface puncture position and depth of the center of the intramuscular nerve dense region in the suboccipital muscle to provide morphological guidance for accurate botulinum toxin A injection to treat headaches caused by increased suboccipital muscle tension. Methods Twenty-four cadavers aged 66.5 ± 5.3 years were studied. The curve line connecting occipital eminence or mastoid process and spinous process of the 7th cervical vertebrae was considered the longitudinal reference line (L) and horizontal reference line (H), respectively. Sihler's staining, barium sulfate labeling, and CT were employed. The body surface projection point of the center of the intramuscular nerve dense region was designated as P. The projection of the center of the intramuscular nerve dense region was in the opposite direction across the transverse plane and was recorded as P'. The intersections of the vertical line through point P and lines L and H were designated as PL and PH. The percentage position of the PH and PL points on the H and L lines and the depths of the center of intramuscular nerve dense regions were identified. Results Sihler's staining showed one intramuscular nerve-dense region in each suboccipital muscle. The PH of the center of the intramuscular nerve dense region was located at 51.40, 45.55, 20.55, and 43.50%. The PL was located at 31.38, 30.08, 16.91, and 52.94%. The depth of the center of the intramuscular nerve dense region was at 22.26, 22.54, 13.14, and 27.30%. These percentage values are all the means. Conclusion Accurately defining the body surface position and depth of the center of intramuscular nerve dense region in suboccipital muscles will help to improve botulinum toxin A to target localization efficiency for treating tension-type headache.
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Affiliation(s)
- Jie Wang
- Department of Pain, Affiliated Hospital of Zunyi Medical University, Zunyi, China
| | - Yanrong Li
- Department of Radiology, Affiliated Hospital of Zunyi Medical University, Zunyi, China
| | - Meng Wang
- Department of Anatomy, Zunyi Medical University, Zunyi, China
| | - Shengbo Yang
- Department of Anatomy, Zunyi Medical University, Zunyi, China
- *Correspondence: Shengbo Yang
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Kitamura K, Hayashi S, Jin ZW, Yamamoto M, Murakami G, Rodríguez-Vázquez JF, Yamamoto H. Fetal cervical zygapophysial joint with special reference to the associated synovial tissue: a histological study using near-term human fetuses. Anat Cell Biol 2021; 54:65-73. [PMID: 33594011 PMCID: PMC8017452 DOI: 10.5115/acb.20.265] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Revised: 11/08/2020] [Accepted: 11/18/2020] [Indexed: 01/14/2023] Open
Abstract
Human fetal cervical vertebrae are characterized by the large zygapophysial joint (ZJ) extending posteriorly. During our recent studies on regional differences in the shape, extent, and surrounding tissue of the fetal ZJ, we incidentally found a cervical-specific structure of synovial tissues. This study aimed to provide a detailed evaluation of the synovial structure using sagittal and horizontal sections of 20 near-term fetuses. The cervical ZJ consistently had a large cavity with multiple recesses at the margins and, especially at the anterior end, the recess interdigitated with or were located close to tree-like tributaries of the veins of the external vertebral plexus. In contrast to the flat and thin synovial cell lining of the recess, the venous tributary had cuboidal endothelial cells. No or few elastic fibers were identified around the ZJ. The venous-synovial complex seems to be a transient morphology at and around birth, and it may play a role in the stabilization of the growing cervical ZJ against frequent spontaneous dislocation reported radiologically in infants. The venous-synovial complex in the cervical region should be lost and replaced by elastic fibers in childhood or adolescence. However, the delayed development of the ligament flavum is also likely to occur in the lumbar ZJ in spite of no evidence of a transient venous-synovial structure. The cuboidal venous endothelium may simply represent the high proliferation rate for the growing complex.
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Affiliation(s)
- Kei Kitamura
- Department of Histology and Embryology, Tokyo Dental College, Tokyo, Japan
| | - Shogo Hayashi
- Department of Anatomy, Division of Basic Medical Science, Tokai University School of Medicine, Kanagawa, Japan
| | - Zhe Wu Jin
- Department of Anatomy, Wuxi School of Medicine, Jiangnan University, Wuxi, China
| | | | - Gen Murakami
- Division of Internal Medicine, Jikou-kai Clinic of Home Visits, Sapporo, Japan
| | | | - Hitoshi Yamamoto
- Department of Histology and Embryology, Tokyo Dental College, Tokyo, Japan
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Cho KH, Morimoto I, Yamamoto M, Hanada S, Murakami G, Rodríguez-Vázquez JF, Abe S. Fetal development of the human trapezius and sternocleidomastoid muscles. Anat Cell Biol 2020; 53:405-410. [PMID: 33361543 PMCID: PMC7769109 DOI: 10.5115/acb.20.202] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Revised: 10/11/2020] [Accepted: 10/29/2020] [Indexed: 11/27/2022] Open
Abstract
At present, there is no photographic evidence of splitting of the trapezius and sternocleidomastoid muscles (SCMs), which share a common anlage that extends caudally toward the limb bud in the embryo at a length of 9 mm. Therefore, the aim of the present study was to identify which structures divide the caudal end of the common anlage at the first sign of splitting into two muscles. In 11 mm-long specimens, the SCM and trapezius muscles were identified as a single mesenchymal condensation. In 15 and 18 mm-long specimens, the SCM and trapezius muscles were separated and extended posteriorly and lymphatic tissues appeared in a primitive lateral cervical space surrounded by the SCM (anterior). In 21 mm-long specimens, the lymphatic vessels were dilated and the accompanying afferents were forming connections with the subcutaneous tissue through a space between the SCM and trapezius muscles. In 27 mm-long specimens, cutaneous lymphatic vessels were evident and had entered the deep tissue between the SCM and trapezius muscles. Vascular dilation may be viewed as a result of less mechanical stress or pressure after muscle splitting.
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Affiliation(s)
- Kwang Ho Cho
- Department of Neurology, Wonkwang University School of Medicine and Hospital, Institute of Wonkwang Medical Science, Iksan, Korea
| | | | | | - Shinya Hanada
- Department of Anatomy, Tokyo Dental College, Tokyo, Japan
| | - Gen Murakami
- Division of Internal Medicine, Jikou-kai Clinic of Home Visits, Sapporo, Japan
| | | | - Shinichi Abe
- Department of Anatomy, Tokyo Dental College, Tokyo, Japan
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Kitamura K, Kim JH, Cho KH, Murakami G, Rodríguez-Vázquez JF, Yamamoto H. Regional differences in zygapophysial joint cavities: A histological study of human fetuses. Anat Rec (Hoboken) 2020; 304:979-990. [PMID: 33034079 DOI: 10.1002/ar.24532] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Revised: 07/22/2020] [Accepted: 08/05/2020] [Indexed: 11/09/2022]
Abstract
Human zygapophysial joints (ZJ) have regional differences in shape and orientation during prenatal growth. However, there is limited knowledge of the synovial recess during fetal development. We examined sagittal and horizontal histological sections of the vertebral columns of 30 human fetuses at gestational ages of 8-37 weeks. Fetuses of all gestational ages had subaxial cervical articular processes that were thicker than in the thoracolumbar regions, and as large as the corresponding vertebral bodies. A small or large synovial recess extending beyond the articular cartilage was evident at most regions. The cervical ZJ had large or deep recesses that extended inferiorly in midterm fetuses and posteromedially along the vertebral pedicle and lamina in near-term fetuses. Likewise, the thoracic ZJ had small recesses that extended superiorly in midterm fetuses and medially in near-term fetuses. The lumbar recesses extended laterally beyond the medially shifted articular cartilage of the upper adjacent vertebrae in near-term fetuses and the lumbar articular surface was smallest in the three regions at all stages. At any region, a deep recess appeared before an area expansion of the ZJ cartilage. A drastic change in direction and size of the prenatal recess seemed to occur depending on a possible minute dislocation of the ZJ. In particular, a deep posteromedial recess of the cervical ZJ, which extended far beyond the articular cartilage, might be necessary to maintain high flexibility suitable for the strong flexion posture in utero.
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Affiliation(s)
- Kei Kitamura
- Department of Histology and Embryology, Tokyo Dental College, Tokyo, Japan
| | - Ji Hyun Kim
- Department of Anatomy, Jeonbuk National University Medical School, Jeonju, Republic of Korea
| | - Kwang Ho Cho
- Department of Neurology, Wonkwang University School of Medicine and Hospital, Iksan, Republic of Korea
| | - Gen Murakami
- Division of Internal Medicine, Jikou-kai Clinic of Home Visits, Sapporo, Japan
| | | | - Hitoshi Yamamoto
- Department of Histology and Embryology, Tokyo Dental College, Tokyo, Japan
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Ishii M, Cho KH, Kitamura K, Yamamoto M, Murakami G, Rodríguez-Vázquez JF, Abe SI. Development and growth of the craniocervical junction with special reference to topographical relationship between the occipital basion, the anterior arch of atlas, and the odontoid process of axis: A study using human fetuses. Anat Rec (Hoboken) 2020; 304:353-365. [PMID: 32396695 DOI: 10.1002/ar.24424] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 02/11/2020] [Accepted: 03/17/2020] [Indexed: 12/13/2022]
Abstract
The embryonic occipital bone and odontoid process of the axis are attached and connected by the notochord, but become separated in later development and growth. With special attention to the process of separation, we examined sagittal sections of the craniocervical junction in 18 human fetuses at 8-16 weeks and 22 fetuses at 31-37 weeks. At 8-9 weeks, the anterior arch of atlas was always seen overriding the occipital basal part. The odontoid process was close to the occipital with or without a transient joint cavity until 16 weeks. Near term, the top of the odontoid process was usually higher than the anterior arch, but the former was sometimes (7 of 22) at a level almost equal to or lower than the latter. The apical ligament was evident in a few specimens (5 of 22). A distance between the occipital basion and odontoid process was sometimes less than 1.5 mm (8 of 22) or less than half the thickness of the arch (10 of 22). A transient joint cavity between the basion and odontoid process was often (10 of 22). In three fetuses near term, the atlanto-occipital joint cavity was continuous with the median atlanto-axial joint cavity, and the anterior arch was overriding the occipital basal part. Therefore, rather than stage or age, individual differences were evident in the topographical relationship between the three bony elements at the craniocervical junction. An understanding of the embryology and normal development will aid in the correct interpretation of radiologic images of the pediatric cervical spine.
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Affiliation(s)
| | - Kwang Ho Cho
- Department of Neurology, Wonkwang University School of Medicine and Hospital, Institute of Wonkwang Medical Science, Iksan, Republic of Korea
| | - Kei Kitamura
- Department of Histology and Embryology, Tokyo Dental College, Tokyo, Japan
| | | | - Gen Murakami
- Department of Anatomy, Tokyo Dental College, Tokyo, Japan.,Division of Internal Medicine, Jikou-kai Clinic of Home Visits, Sapporo, Japan
| | | | - Shin-Ichi Abe
- Department of Anatomy, Tokyo Dental College, Tokyo, Japan
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