椎动脉和第1颈神经穿经硬膜处的形态学特点及其与高血压颈枕痛的关系

Morphological characteristics of the vertebral artery and the first cervical nerve through dura meter and its relation to occipital pain in hypertension

目的观察椎动脉和第1颈神经穿经硬膜处的形态特点及毗邻结构,探讨高血压合并枕颈部疼痛的发生机制。方法头颈部标本18具,解剖剥离法暴露,观察椎动脉穿经硬膜处部位及毗邻结构、椎动脉与第1颈神经(C1)的位置关系。结果椎动脉在寰枕外侧关节内后侧穿经硬膜,穿经处形成边缘光滑的圆孔,直径6.5~9.0 mm,硬膜与椎动脉外膜由纤维结缔组织连结。C1神经前后根自脊髓发出向外侧走行于椎动脉内侧并在其下方相伴共同穿经硬膜孔(100%),其中与动脉壁相贴者66.7%(12例);神经嵌入动脉壁者22.2%(4例);隔有硬膜组织者11.1%(2例)。C1神经根出孔后走行于椎动脉与椎动脉沟之间。结论椎动脉穿经硬膜孔处位置固定,孔边缘致密,限制椎动脉扩张,利于颈椎活动时维持椎动脉供血,当全身血压波动时椎动脉管径不会产生明显变化,以维持后循环血液动力学稳定,但血压升高有可能将C1颈神经根卡压在硬膜边缘,椎动脉搏动刺激C1颈神经根导致椎枕肌痉挛,出现枕颈部疼痛。这可能是高血压合并枕颈部症状的形态学基础。

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.