The Correct Answer is: B
The typical vertebra has a body and a neural/vertebral arch surrounding the vertebral foramen (Figure 2-58). The neural arch is composed of two pedicles and two laminae that support four articular processes, two transverse processes, and one spinous process. The pedicles are short, thick processes extending back from the posterior aspect of the vertebral body, each one sustaining a lamina. The laminae extend
posteriorly to the midline and join to form the spinous process. Each pedicle has notches superiorly and inferiorly (superior and inferior vertebral notches) that—with adjacent vertebrae—form the intervertebral foramina, through which the spinal nerves pass. The neural arch also has lateral transverse processes for muscle attachment and superior and inferior articular processes for the formation of apophyseal joints (classified as diarthrotic). The vertebral column permits flexion, extension,
and lateral and rotary motions through its various articulations. (Frank, Long, and Smith, 11th ed., vol. 1, p. 376)
Which projection of the lumbar spine demonstrates the zygapophyseal joints closer to the IR?
The zygapophyseal facet joints of the second through seventh cervical vertebrae lie at right angles to the midsagittal plane and are clearly shown in a lateral projection (Fig. 8-10, A).
Cervical, Thoracic and Lumbar Spine Joints and Foramina Positioning.
The PA projection (Judd method) is intended to demonstrate the zygapophyseal joint between C1 and C2. The posterior cervical oblique projections demonstrate the intervertebral foramina and pedicles on the side closest to the image receptor.
Which of the following positions will demonstrate the lumbosacral zygapophyseal articulation? The correct answer is (C). The articular facets (zygapophyseal joints) of the L5-S1 articulation form a 30-degree angle with the MSP; they are, therefore, well demonstrated in a 30-degree oblique position.