Plain Radiography Anatomy Study Bundle

Comprehensive vocabulary flashcards covering anatomical landmarks and radiographic features across plain radiography studies of the lumbar spine, orthopantomogram (OPG), cervical spine, skull, and thoracic spine.

Pars interarticularis

The region of the lamina located between the superior and inferior articular processes in the lumbar vertebra, which forms the neck of the 'Scottie dog' on oblique lumbar projections and is susceptible to spondylolysis.

Scottie dog sign

The distinctive radiological appearance of posterior vertebral elements seen on oblique lumbar spine radiographs resembling a Scottish Terrier dog, where the pedicle forms the eye, transverse process forms the snout, and pars interarticularis forms the neck.

Psoas major shadow

The linear soft-tissue radiographic contour extending obliquely along the lateral margins of the lumbar spine toward the iliac crest on AP lumbar views.

Zygapophyseal joint (Z joint)

The synovial facet joint formed between the inferior articular process of a superior vertebra and the superior articular process of the inferior adjacent vertebra.

Intervertebral foramen

The lateral opening formed between the inferior vertebral notch of one vertebra and the superior vertebral notch of the adjacent vertebra through which spinal nerves exit, best evaluated on lateral radiographs.

Sacral ala

The broad, wing-like lateral mass located on each side of the upper sacrum that articulates laterally with the ilium at the sacroiliac joint.

Orthopantomogram (OPG)

A panoramic plain radiographic technique that produces a single continuous image of the maxilla, mandible, dentition, and temporomandibular joints.

Lamina dura

The thin, dense radiopaque cortical bone layer that lines the tooth socket and surrounds the roots of normal teeth on dental radiographs.

Mandibular canal

The radiolucent neurovascular canal coursing through the mandibular ramus and body between the mandibular foramen and the mental foramen, carrying the inferior alveolar nerve and vessels.

Mental foramen

A bilateral radiolucent aperture situated on the anterolateral surface of the mandible below the premolar apices through which the mental nerve and vessels exit.

Coronoid process of the mandible

The thin, triangular anterior superior bony projection of the mandibular ramus separated from the posterior condylar process by the mandibular notch.

Dentin

The calcified intermediate layer of the tooth structure underlying enamel and cementum that encloses the central pulp chamber and root canal.

Tooth pulp

The innermost radiolucent chamber and canal containing the vascular and neural tissues of the tooth.

Uncinate process

A hook-like bony elevation located on the posterolateral superior surface of cervical vertebral bodies ($\text{C3}$ through $\text{C7}$) that forms uncovertebral joints.

Odontoid process (Dens)

A tooth-shaped vertical projection rising from the superior body of the second cervical vertebra ($\text{C2}$/axis), serving as the pivot point around which the atlas ($\text{C1}$) rotates.

Atlantodens interval (ADI)

The horizontal radiolucent distance measured between the posterior margin of the anterior arch of $\text{C1}$ and the anterior surface of the odontoid process on a lateral cervical spine radiograph.

Articular pillar

The column of bone formed by the vertical stacking and articulation of the superior and inferior articular processes of adjacent cervical vertebrae.

Vertebra prominens

The seventh cervical vertebra ($\text{C7}$), identifiable on plain radiographs by its long, prominent, and non-bifid spinous process.

Spinolaminar line

The continuous smooth radiological curve on a lateral cervical radiograph connecting the junctions of the laminae and spinous processes across adjacent cervical levels.

Open-mouth (Odontoid/PEG) view

A specialized AP cervical radiograph taken with the patient's mouth wide open to project the dens, lateral masses of $\text{C1}$, and atlanto-axial joints free of superimposed teeth and maxilla.

Waters view (Occipitomental / OM skull view)

A plain radiographic projection taken with the patient's neck extended so the chin contacts the image receptor, optimally demonstrating the maxillary sinuses, orbital rims, zygomatic arches, and nasal cavity.

Caldwell view (PA skull view)

A posteroanterior skull radiograph angled approximately $15^\circ$ caudad, primarily used to demonstrate the frontal and anterior ethmoid sinuses and superior orbital margins free of petrous ridge overlap.

Crista galli

A vertical triangular midline projection of the ethmoid bone extending into the anterior cranial fossa, visualized above the nasal septum on frontal skull radiographs.

Pituitary fossa (Sella turcica)

A saddle-shaped bony depression in the sphenoid bone that accommodates the pituitary gland, bounded anteriorly by the anterior clinoid processes and posteriorly by the posterior clinoid processes on lateral skull radiographs.

Coronal suture

The serrated transverse cranial joint separating the frontal bone from the anterior borders of the parietal bones.

Lambdoid suture

The inverted Y- or V-shaped cranial joint separating the posterior border of the parietal bones from the occipital bone.

Sphenoid sinus

The paired, air-filled paranasal sinus located inferior and anterior to the sella turcica within the body of the sphenoid bone, clearly visualized on lateral skull radiographs.

Costovertebral joint

The synovial articulation connecting the head of a rib with the costal facets or demifacets of adjacent thoracic vertebral bodies and the intervening intervertebral disc.

Costotransverse joint

The synovial articulation formed between the tubercle of a rib and the anterior surface of the transverse process of the corresponding thoracic vertebra.

Interlaminar space

The radiolucent functional window located between the laminae of adjacent vertebrae seen on frontal (AP/PA) spine radiographs.

Vertebral endplate

The layer of dense, flattened cortical bone forming either the superior or inferior articular surface of a vertebral body directly interfacing with an intervertebral disc.

Lateral mass of C1

The robust bilateral bony bulk of the atlas that bears the superior articular facets for the occipital condyles and the inferior articular facets for the axis ($\text{C2}$).