Abstract: Objective　To observe the morphological characteristics and adjacent structures of the vertebral artery and the first cervical nerve through the dura meter, and to explore the mechanism of hypertension combined with occipitocervical pain.   Methods    Eighteen cranial-neck specimens were dissected and exposed to observe the position of the vertebral artery and adjacent structures, relationship between the first cervical nerve and vertebral artery.　Results　The vertebral artery passed through the dura mater in the posterior part of the lateral atlanto-occipital joint, forming a round hole with smooth edge. Diameter of the hole was 6.5~9.0 mm. The dura mater and the adventitia of the vertebral artery were connected by fibrous connective tissue. The anterior and posterior roots of C1 nerve originated from the spinal cord and ran laterally to the medial side of the vertebral artery and were accompanied by the dural foramen below it (100%), among which 12 cases (accounting for 66.7%) were attached to the artery wall. Four patients (accounting for 22.2%) had nerve insertion into arterial wall. Dural organizers were found in 2 cases (accounting for 11.1%). After exiting the foramen, the C1 nerve root passed the vertebral artery and the vertebral artery sulcus.　Conclusions　The position of vertebral artery is fixed, the hole edge is density. The position limits the expansion of vertebral artery, which is helpful to maintain vertebral artery cervical activity. When systemic blood pressure fluctuates, in order to maintain the stability of circulating hemodynamics, vertebral artery diameter does not change significantly. However, elevated blood pressure may press C1 cervical nerve root into the dural edge. The pulsation of the vertebral artery stimulates the C1 cervical nerve root, leading to vertebrooccipital muscle spasm and occipital neck pain. This may be the morphological basis of hypertension with occipitocervical symptoms. 

Key words: Vertebral artery；　Dura mater；　C1 nerve；　Occipital pain；　Hypertension