Chest, Extremities, Spine, Skull/Sinuses, and Podiatric Modules
Key Takeaways
- Every Limited Scope candidate takes the 100-question Core module plus only the procedure modules the state licensing agency assigned for that license type, as shown on the Candidate Status Report (CSR).
- Scored procedure counts are Chest 20, Extremities 25, Skull/Sinuses 20, Spine 25, and Podiatric 20; each module adds five unscored pilot questions (25 or 30 total items).
- Chest, Skull/Sinuses, and Podiatric are timed at 25 minutes; the larger Extremities and Spine modules get 30 minutes, so pacing differs by module.
- Positioning is the highest-emphasis skill across modules; anatomy and image evaluation follow closely, while equipment and procedure adaptation carry less weight.
- Podiatric is its own module focused on weightbearing foot/ankle work and does not duplicate the general Extremities mix; study only assigned modules first.
State-Assigned Procedure Modules
The ARRT (American Registry of Radiologic Technologists) Limited Scope of Practice in Radiography exam is modular. Everyone takes the Core module, but the procedure modules are assigned by the state licensing agency for the license type you applied for. ARRT writes, delivers, and scores the exam on behalf of states; it does not let you add or drop modules at the test center. Your Candidate Status Report (CSR) is the single source of truth for which modules you will see and the 90-day window in which you must test.
This matters because two people both "taking Limited Scope" can sit very different exams. One state may assign Chest only. Another may assign Chest, Extremities, and Spine. A podiatric x-ray license uses the Podiatric module rather than the general extremity mix. Build your final review from the CSR, never from a national guess or a classmate's load.
Module Counts, Timing, and Internal Weight
| Procedure module | Scored items | Pilots | Time | Main internal split to respect |
|---|---|---|---|---|
| Chest | 20 | 5 | 25 min | Routine PA/AP and lateral chest dominate; decubitus and lordotic views are smaller but testable |
| Extremities | 25 | 5 | 30 min | Upper and lower extremity roughly equal; pectoral girdle (shoulder/clavicle/scapula) is smaller |
| Skull/Sinuses | 20 | 5 | 25 min | Cranium and paranasal sinuses carry the bulk; facial bones, orbits, nasal bones, and mandible are smaller |
| Spine | 25 | 5 | 30 min | Cervical and lumbar largest; thoracic next; sacrum/coccyx/SI joints and scoliosis are smaller |
| Podiatric | 20 | 5 | 25 min | Foot/toes dominate, ankle follows, calcaneus is small but high-yield for its special axial view |
The most reliable way to study a module is to turn each projection into a short route sheet: patient position, projection/beam path, central-ray (CR) entry point and any angle, image-receptor (IR) placement, breathing instruction if relevant, the anatomy that must appear, and the correction you would make if the image is rotated, clipped, underexposed, or blurred.
What Each Module Rewards
Chest rewards upright thinking. Routine work starts with the upright PA at a 72-inch (180 cm) source-to-image distance (SID) to minimize heart magnification, with the patient suspending respiration on the second full inspiration so 10 posterior ribs show above the diaphragm. Know why a lateral decubitus (gravity plus a horizontal beam to layer air or fluid) or a lordotic AP (to project clavicles above the apices) is ordered, rather than memorizing names.
Extremities rewards joint coverage and true projection logic. Long bones require both adjacent joints when the protocol demands it, and a rotation that opens one joint space closes another. The exam expects you to recognize, for example, that a true AP elbow needs the hand supinated, or that internal/external humeral rotation moves the greater tubercle in or out of profile.
Skull/Sinuses rewards head-line precision. Small changes in the orbitomeatal line (OML), infraorbitomeatal line (IOML), chin position, head rotation, or CR angle move dense petrous pyramids into or out of the diagnostic field. Sinus imaging is tied to upright positioning with a horizontal beam because air-fluid levels only appear when gravity acts on them.
Spine rewards safety and alignment. Cervical trauma demands a horizontal-beam lateral with no movement before clearance; the lateral C-spine must show C7-T1. Lumbar work often depends on reducing lordosis (flexed knees) or supporting waist sag so the spine stays parallel to the IR.
Podiatric rewards functional, weightbearing positioning because foot and ankle alignment changes under load, with named views such as the dorsoplantar (DP), the lateral, and the calcaneal axial.
Worked Example: Reading the CSR
Suppose your CSR shows Core plus Chest and Spine. Your exam is then 100 + 20 + 25 = 145 scored items (plus 35 pilots) across three timed blocks: 1:55 for Core, 25 minutes for Chest, and 30 minutes for Spine. A candidate who instead studies all five modules equally wastes roughly 40% of procedure prep on Extremities, Skull/Sinuses, and Podiatric content that will never appear. The CSR turns an open-ended subject into a finite, schedulable target.
A second trap is assuming Podiatric is just "feet inside Extremities." It is a distinct module that leans on weightbearing dorsoplantar and lateral foot views, the medial-oblique foot, the ankle mortise, and the calcaneal axial. The Extremities module covers the appendicular skeleton broadly (fingers through shoulder girdle, toes through knee) but does not stress weightbearing podiatric mechanics. If your CSR names one, do not substitute the other.
Module Selection Checklist
- Read the CSR before drafting any study calendar, and confirm the 90-day testing window.
- Allocate study time by assigned scored counts, not personal comfort.
- Drill high-count areas first: routine chest, upper/lower extremity, major skull/sinus groups, cervical/lumbar spine, and podiatric foot/toes.
- For each projection, write the CR entry point, any tube angle, the IR size and orientation, and the structures that must be demonstrated.
- Keep one mixed procedure session weekly so shared errors (rotation, clipped anatomy, off-centering) do not stay hidden until exam day.
- Re-derive timing per module so a 30-minute Spine block does not feel like a 25-minute Chest block.
High-Yield Central-Ray and SID Anchors
A handful of central-ray (CR) and SID facts recur across module forms; commit these to memory as anchors and reason the rest from them. PA chest: 72-inch SID, CR to T7 (inferior scapular angle). AP/PA hand and wrist: 40-inch SID, CR to the third MCP joint (hand) or midcarpal area (wrist). AP knee: CR about 0.5 inch below the apex of the patella, with a slight cephalad angle that varies by patient thickness. AP and lateral ankle: CR to the midpoint between the malleoli. Lateral cervical spine: 72-inch SID, CR to C4, and the image must include C7-T1.
AP lumbar spine: 40-inch SID, CR to the level of the iliac crest (about L4-L5). Sinuses (parietoacanthial/Waters): upright, horizontal beam, CR exiting the acanthion. Calcaneal axial (plantodorsal): CR angled 40 degrees cephalad to the long axis of the foot, entering at the base of the third metatarsal. These are not the only projections tested, but knowing the anchor SID, CR point, and any required angle lets you derive an unfamiliar view instead of guessing.
A candidate's CSR lists Chest, Extremities, and Spine. Which final-review plan best matches the way Limited Scope procedure modules are assigned and timed?