Radiographic Procedures · ARRT 2025
Positioning Foundations
Anatomic position, body planes (sagittal, coronal, transverse), projection vs. position, and the standard radiographic terminology that drives every exam on the ARRT.
Overview
Positioning Foundations is the vocabulary chapter. Before you can study chest, spine, or extremity positioning, you have to know what AP means, what oblique means, and what plane the central ray is parallel to. The ARRT registry assumes fluency in this language and will mark questions wrong if you confuse projection (the path of the central ray through the body) with position (how the body is placed) or view (what the radiologist sees).
The anatomic position is the universal reference: standing erect, palms forward, feet pointing ahead. From this, every directional term is defined. Anterior/posterior. Medial/lateral. Proximal/distal. Superior/inferior. Cranial/caudal. The three reference planes: sagittal (divides left/right), coronal (divides anterior/posterior), and transverse (divides superior/inferior). The midsagittal plane is a specific sagittal plane through the midline.
Projections describe central-ray entry and exit: AP (anterior to posterior), PA (posterior to anterior), lateral, oblique. Positions describe body orientation: supine, prone, recumbent, erect. Decubitus is a specialized position, patient lying down with a horizontal central ray (left lateral decubitus = patient on left side, beam horizontal). The chapter also covers radiographic markers (always use lead, always inside the collimated field), proper SID and OID, and the basics of central ray angulation. Mastery here pays dividends through every procedures chapter that follows.
What you’ll learn in this chapter
The 17 lessons in this chapter break down as follows. The full lesson content is unlocked when you start a free account.
The Body's Reference Systems
- Three Pillars of Positioning Excellence
- Body Planes
- Body Habitus: Why Anatomy Moves
- Mapping the Abdomen
- Surface Landmarks for Precise Positioning
The Imaging Lexicon
- Position vs Projection vs View
- Standard Body Positions
- The Vocabulary of Skeletal Motion
- Why a Minimum of Two Projections
Procedural Excellence
- The Professional Workflow
- Controlling Motion Artifacts
- Adapting Projections for the Patient
- Watch for Hidden Artifacts
Knowledge Check
- Question 1 of 4 Quiz
- Question 2 of 4 Quiz
- Question 3 of 4 Quiz
- Question 4 of 4 Quiz
Key terms in this chapter
These are the 7 terms most likely to appear on the ARRT registry from this chapter. Use them as a flashcard pre-quiz.
- Anatomic Position
- Standing erect, palms forward, feet pointing ahead. The universal reference for all directional terminology.
- Sagittal Plane
- Vertical plane that divides the body into left and right portions. Midsagittal divides into equal halves.
- Coronal Plane
- Vertical plane that divides the body into anterior and posterior portions. Also called the frontal plane.
- Transverse Plane
- Horizontal plane that divides the body into superior and inferior portions. Also called the axial or horizontal plane.
- Projection
- Path of the central ray through the body (AP, PA, lateral, oblique). Distinct from position.
- Position
- How the body is placed on the table (supine, prone, recumbent, erect, decubitus). Distinct from projection.
- Lateral Decubitus
- Patient lying on their side with a horizontal central ray. Used to demonstrate air-fluid levels and free air.
Sample practice question: Patient Interactions
One free sample from the 124-question Patient Interactions bank. See the format, the rationale style, and the difficulty before you sign up.
A patient is scheduled for an upper GI series. Before bringing the patient into the fluoroscopy room, which of the following is the radiographer's FIRST priority?
Show answer and rationale
A, Incorrect: Order verification matters, but it follows patient identification.
B, Correct: Correct. The Joint Commission requires two-factor identification (typically name and DOB) before any procedure. Wrong-patient errors are the most common preventable adverse event in imaging.
C, Incorrect: Barium administration begins after the patient is identified and consented.
D, Incorrect: Positioning happens after identification, history-taking, and consent confirmation.
Read the full chapter, free.
The free tier unlocks one complete chapter (17 lessons), 50 practice questions, and 1 sample timed exam. No credit card required.
Frequently asked questions
What does the ARRT Radiography Radiographic Procedures category cover?
Positioning Foundations is the vocabulary chapter. Before you can study chest, spine, or extremity positioning, you have to know what AP means, what oblique means, and what plane the central ray is parallel to. The ARRT registry assumes fluency in this language and will mark questions wrong if you confuse projection (the path of the central ray through the body) with position (how the body is placed) or view (what the radiologist sees).
How many lessons are in the Positioning Foundations chapter?
This chapter contains 17 lessons across 4 sections, plus a knowledge-check quiz at the end. The full lesson content is unlocked with a Premium subscription. The free tier includes the first chapter complete.
Is this chapter aligned with the ARRT 2025 Content Specifications?
Yes. Every chapter on this site maps directly to the ARRT Radiography Content Specifications effective 2025. This chapter falls under the Radiographic Procedures domain of the official ARRT exam blueprint.