Cervical region

Prepared by hiwa, aras
University of garmian college of medicine
2022

1. Cervical region

2. Contents Introduction Bony structure Joints Ligaments Triangles of neck Muscles of neck Nerves

3. Introduction The cervical spine is the most superior portion of the vertebral column, lying between the cranium and the thoracic vertebrae. It consists of seven distinct vertebrae,three of which are given unique characteristics (atypical) The first cervical vertebrae (C1) atlas. The second cervical vertebrae (C2) axis. The seventh cervical vertebrae (C7). Others are typical (C3, C4, C5, C6).

4. Cervical vertebrae(Posterior view)

5. Characteristic Features The cervical vertebrae have three features which distinguish them from thoracic vertebrae: Triangular vertebral foramen. Bifid spinous process – this is where the spinous process splits into two distally. Transverse foramina – holes in the transverse processes. They give passage to the vertebral artery, vein and sympathetic nerves.

6. Atlas The atlas (C1) differs from the other cervical vertebrae in that it has no vertebral body and no spinous process. It also has an articular facet anteriorly, which articulates with the dens of the axis. The atlas also has lateral masses on either side of the vertebral arch, which provide an attachment for the transverse ligament of the atlas. The posterior arch has a groove for the vertebral artery and C1 spinal nerve.

7. Atlas

8. Axis The axis (C2) is easily identifiable due to its dens (odontoid process) which extends superiorly from the anterior portion of the vertebra. The dens articulates with the articular facet of the atlas, in doing so creating the medial atlanto-axial joint, This allows for rotation of the head independently of the torso.

9. Axis

10. Joints The joints of the cervical spine can be divided into two groups – those that are present throughout the vertebral column, and those unique to the cervical spine. There are two different joints present throughout the vertebral column: Between vertebral bodies – adjacent vertebral bodies are joined by intervertebral discs, made of fibrocartilage. This is a type of cartilaginous joint, known as a symphysis. Between vertebral arches – formed by the articulation of superior and inferior articular processes from adjacent vertebrae, It is a synovial type joint.

11. Joints Unique to Cervical Spine The atlanto-axial and atlanto-occipital joints are unique to the cervical spine. The atlanto-axial joints are formed by the articulation between the atlas and the axis: There are two lateral atlanto-axial joints which are formed by the articulation between the inferior facets of the lateral masses of C1 and the superior facets of C2. These are plane type synovial joints. The medial atlanto-axial joint is formed by the articulation of the dens of C2 with the articular facet of C1. This is a pivot type synovial joint. The atlanto-occipital joints consist of an articulation between the spine and the cranium,They occur between then superior facets of the lateral masses of the atlas and the occipital condyles at the base of the cranium. These are condyloid type synovial joints, and permit flexion at the head i.e. nodding

12. Typical cervical vertebrae

13. Ligaments There are six major ligaments to consider in the cervical spine. The majority of these ligaments are present throughout the entire vertebral column. Present throughout Vertebral Column Anterior and posterior longitudinal ligaments: Long ligaments that run the length of the vertebral column, covering the vertebral bodies and intervertebral discs. Ligamentum flavum: Connects the laminae of adjacent vertebrae. Interspinous ligament: Connects the spinous processes of adjacent vertebrae. Unique to Cervical Spine Nuchal ligament: A continuation of the supraspinous ligament. It attaches to the tips of the spinous processes from C1-C7, and also provides the proximal attachment for the rhomboids and trapezius. Transverse ligament of the atlas: Connects the lateral masses of the atlas, and in doing so anchors the dens in place. (Note: Some texts consider the interspinous ligament to be part of the nuchal ligament).

14. Traingles of neck Triangles of neck + contents

15. Submental triangle Muscular triangle Carotid triangle Occipital triangle Submandibular triangle Su praclavicular triangle

16. Muscles and fascia of neck Neck Fascia is divided into superficial and deep The superficial fascia in the neck contains a thin sheet of muscle (the platysma), which begins in the superficial fascia of the thorax, runs upward to attach to the mandible and blend with the muscles on the face, is innervated by the cervical branch of the facial nerve [VII]. the deep cervical fascia is organized into several distinct layers That include: an investing layer, which surrounds all structures in the neck; the prevertebral layer, which surrounds the vertebral column and the deep muscles. the pretracheal layer, which encloses the viscera of the neck; the carotid sheaths, surrounds common carotid art, jugular vein, vagus nerve

17. Cervical nerves Ansa cervicals innervate infrahyoid muscles Accessory nerve (XI) INNERVATES trapezius and sternocleidomastoid Cervical plexus has Muscular branches, phrenic nerve(c3,c4,c5) that innervates diaphragm(sensory, motor) Cervical plexus innervates prevertebral and lateral vertebral cervical muscles Superficial branches(cutsneous) Lesser occipital nerve innervates skin of neck and scalp posterior to auricle Great occpital nerve supplies skin of parotid , ear , mastoid area Transverse Cervical nerve supplie lateral and anterior part of neck Supraclavicular nerve supplies skin above clavicle to rib 2 Brachial plexus supplies upper limb