The following ligaments add stability to the vertebral column:
Anterior longitudinal ligament (ALL): Prevents excessive extension of the spine and increases its thickness as it moves from the cervical to the lumbar region
Posterior longitudinal ligament (PLL): Prevents excessive fl exion of the spine and decreases its thickness as it moves into the lumbar region Supraspinous ligament: Connects the spinous processes of the verte- brae to prevent excessive fl exion
In the cervical spine, there are two atypical vertebrae, neither of which has disks, that have special names ( Fig. 5-5 ). The 1st cervical vertebra (C1) is known as “the atlas,” after the Greek god Atlas, who held the weight of the world on his shoulders. C1 is little more than a bony ring, lacking both trans- verse and spinous processes. On each side is a lateral mass, which forms the superior articular facet and acts like a “washer” as it articulates with the occipital bone of the skull at the occipital condyles. C1 also does not have a true body. Its body is actually formed by the 2nd cervical vertebra (C2), known as “the axis” (named for the odontoid process); it forms the body of C1 when the two come together. The process is held in place by a transverse ligament, and it is this process that enables rotation of the head.
Collectively, the cervical vertebrae are unique because each has a dis- tinct tunnel known as the transverse foramen in each transverse process. This foramen allows a protective passageway for the vertebral arteries that supply blood to the brain.
Bony Landmarks and Surface Anatomy
Many therapists are hesitant to work on the anterior neck because of its delicate structures; however, understanding the structures and how to palpate them should help alleviate this fear.
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Anterior tubercle Anterior arch Superior articular facet Transverse foramen Transverse foramen Transverse process Inferior articular process
Spinous process Lamina
Posterior arch
Posterior tubercle
Dens (odontoid process) Superior articular facet
Body Pedicle Lateral masses Transverse process (a) (b)
Chapter 5 Conditions of the Head and Neck 103
Depending on one’s body type, the posterior tubercle of C1 (see Fig. 5-5 ) is usually too small to palpate; however, it lies midline directly inferior to the external occipital protuberance in the soft tissue space. This is palpated easier in the supine position, which facilitates the relaxation of the neck musculature and allows you to passively fl ex and extend the client’s head. From the posterior neck, the C1 transverse process is located by picking a point midway between the angle of the mandible and the mastoid process. Very gently palpate behind the ear, anterior to the SCM, looking for a bony prominence. You may laterally fl ex the client’s neck passively to help with palpation. The C1 posterior arch is located between the tubercle and the transverse process. To fi nd the location, move laterally from the posterior tubercle on either side; the arch is halfway between the tubercle and the mastoid processes lateral to the paraspinal musculature. The arch, which is palpated easier in the supine position, is the bony landmark for the greater occipital nerve and lymph nodes.
The C2 spinous process is usually the fi rst palpable spinous process and is directly inferior from the external occipital protuberance; it is almost al- ways bifurcated. It is the largest and longest spinous process in the cervical region until C7. From the C2 spinous process, the C2 cervical facet joints are found by moving out lateral to the paraspinal musculature. This is the superior facet of C2. To fi nd the C2 and C3 joints, move inferiorly less than a fi nger’s width. Use caution, as this is typically a tender area.
The C7 spinous process is also known as the vertebral prominens; it is the most prominent and easiest cervical vertebra to palpate. To distin- guish between C7 and C6 or T1, locate what you think is the C7 spinous process. Have the client extend his or her neck to see whether it disap- pears. If the spinous process disappears, move down and repeat the move- ment until fi nding one that does not disappear; this is C7. If the starting spinous process does not disappear, move up until fi nding one that does. The last spinous process before the one that disappeared is C7.
Figure 5-5 The 1st and
2nd vertebrae of the cervical spine.
(a) Atlas. (b) Axis.
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Thyroid cartilage
1st cricoid ring
Anterior cervical triangle
Posterior cervical triangle
Anterior tubercle of C6
Figure 5-6 Soft tissue structures of the cervi- cal spine.
104 Part II Regional Approach to Treatment
At the front of the neck, the hyoid bone lies under the chin above the voice box. Place your thumb and fi rst fi nger on either side of the anterior neck just below the mandible and above the trachea. Gently squeeze, and move your thumb and fi nger back and forth to feel the bone move. Once you think you have it, have the client swallow to feel it elevate. It lies at the level of C3 and can be used as a landmark for that vertebra.