Cervial Spine; anatomy, structure and examination

Cervical Spine

Examination of the cervical spine involves determining whether the injury or pathology occurs in the cervical spine or in a portion of the upper limb. Cyriax1 called this assessment the scanning examination. In the initial assessment of a patient who complains of pain in the neck and/or upper limb, this procedure is always carried out unless the examiner is absolutely sure of the location of the lesion. If the injury is in the neck, the scanning examination is definitely called for to rule out neurological involvement.

Cervical Spine


APPLIED ANATOMY

The cervical spine consists of several pairs of joints. It is an area in which stability has been sacrificed for mobility, making the cervical spine particularly vulnerable to injury because it sits between a heavy head and a stable thoracic spine and ribs. The cervical spine is divided into two areas—the cervicoencephalic for the upper cervical spine and the cervicobrachial for the lower cervical spine. The cervicoencephalic or cervicocranial region (C0 to C2) shows the relationship between the cervical spine and the occiput, and injuries in this region have the potential of involving the brain, brainstem, and spinal cord.  Injuries in this area lead to symptoms of headache, fatigue, vertigo, poor concentration, hypertonia of sympathetic nervous system, and irritability. In addition, there may be cognitive dysfunction, cranial nerve dysfunction, and sympathetic system dysfunction.

The atlanto-occipital joints (C0 to C1) are the two uppermost joints. The principal motion of these two joints is flexion-extension (15° to 20°), or nodding of the head. Side flexion is approximately 10°, whereas rotation is negligible. The atlas (C1) has no vertebral body as such. During development, the vertebral body of C1 evolves into the odontoid process, which is part of C2. The atlanto-occipital joints are ellipsoid and act in unison.

There are several ligaments that stabilize the atlantooccipital joints. Anteriorly and posteriorly are the atlanto-occipital membranes. The anterior membrane is strengthened by the anterior longitudinal ligament. The posterior membrane replaces the ligamentum flavum between the atlas and occiput. The tectorial membrane, which is a broad band covering the dens and its ligaments, is found within the vertebral canal and is a continuation of the posterior longitudinal ligament. The atlanto-axial joints (C1 to C2) constitute the most mobile articulations of the spine. Flexion-extension is approximately 10°, and side flexion is approximately 5°. Rotation, which is approximately 50°, is the primary movement of these joints. With rotation, there is a decrease in height of the cervical spine at this level as the vertebrae approximate because of the shape of the facet joints. The odontoid process of C2 acts as a pivot point for the rotation. This middle, or median, joint is classified as a pivot (trochoidal) joint. The lateral atlanto-axial, or facet, joints are classified as plane joints. Generally, if a person can talk and chew, there is probably some motion occurring at C1 to C2. At the atlanto-axial joints, the main supporting ligament is the transverse ligament of the atlas, which holds the dens of the axis against the anterior arch of the atlas.

Symptoms related to the vertebral artery include vertigo, nausea, tinnitus, “drop attacks” (falling without fainting), visual disturbances, or, in rare cases, stroke or death.

The lower cervical spine (C3 to C7) is called the cervicobrachial area, since pain in this area is commonly referred into the upper extremity.2,3 Pathology in this region leads to neck pain alone, arm pain alone, or both neck and arm pain. Thus, symptoms include neck and/ or arm pain, headaches, restricted range of motion (ROM), paresthesia, altered myotomes and dermatomes, and radicular signs. pine (C1 to C7). The upper four facet joints in the two upper thoracic vertebrae (T1 to T2) are often included in the examination of the cervical spine. The superior facets of the cervical spine face upward, backward, and medially; the inferior facets face downward, forward, and laterally flexion without both occurring to some degree together.

These joints move primarily by gliding and are classified as synovial (diarthrodial) joints. The capsules are lax to allow sufficient movement. At the same time, they provide support and a check-rein type of restriction at end range. The greatest flexion-extension of the facet joints occurs between C5 and C6; however, there is almost as much movement at C4 to C5 and C6 to C7. Because of this mobility, degeneration is more likely to be seen at these levels. The neutral or resting position of the cervical spine is slightly extended. The close packed position of the facet joints is complete extension. In the cervical spine, the transverse processes are made up of two parts: the anterior portion that provides the foramen for the vertebral body, and the posterior portion containing the two articular facets. In the cervical spine, the spinous processes are at the level of the facet joints of the same vertebra. Generally, the spinous process is considered to be absent or at least rudimentary on C1. This is why the first palpable vertebra descending from the external occiput protuberance is the spinous process of C2.

Although there are seven cervical vertebrae, there are eight cervical nerve roots. This difference occurs because there is a nerve root exiting between the occiput and C1 that is designated the C1 nerve root. In the cervical spine, each nerve root is named for the vertebra below it. As an example, C5 nerve root exists between the C4 and C5 vertebrae. In the rest of the spine, each nerve root is named for the vertebra above; the L4 nerve root, for example, exists between the L4 and L5 vertebrae. The switch in naming of the nerve roots from the one below to the one above is made between the C7 and T1 vertebrae. The nerve root between these two vertebrae is called C8, accounting for the fact that there are eight cervical nerve roots and only seven cervical vertebrae.

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