Trauma Radiography: Positioning and Protocols for the Emergency Setting

Introduction: The Trauma Technologist's Role

Trauma radiography prioritizes the clinical question, speed and diagnostic quality while minimizing movement of a potentially unstable spine, pelvis, hip or limb. The radiographer works under the trauma leader's direction; imaging must not interrupt airway, breathing or circulation treatment, and a life-threatening condition such as tension pneumothorax is treated clinically rather than waiting for an image.

Primary-Survey Imaging: Protocol and Patient Dependent

During resuscitation, imaging is selected by physiology, mechanism, examination and local trauma workflow. Portable AP chest and AP pelvis radiographs can rapidly identify major thoracic or pelvic abnormalities and show tubes or lines. eFAST may be performed concurrently. Hemodynamically stable patients commonly proceed to contrast-enhanced CT when indicated; unstable patients receive only imaging that can change immediate management without delaying treatment.

Cervical-Spine Motion Restriction and Imaging

Maintain the head, neck and torso in alignment until an authorized clinician clears motion restriction. Do not remove or reposition a collar for radiography unless the trauma clinician directs a controlled maneuver. ACS permits clinical collar removal in an appropriate awake, asymptomatic adult meeting all required low-risk findings; this is a clinician assessment, not a radiographer decision. If adult blunt-trauma imaging is indicated, ACR rates CT without IV contrast “Usually Appropriate” and cervical radiography “Usually Not Appropriate.”

If a Horizontal-Beam Lateral Is Specifically Ordered

A limited cross-table lateral may still appear in a local protocol when CT is unavailable or for a specific non-clearance purpose. Keep the patient supine and motion-restricted; place the detector vertically close to the shoulder without levering the neck or torso; use a horizontal ray perpendicular to the detector, centered near C4; and aim to include the skull base through C7-T1. Use the facility technique chart, approved source-to-image distance and exposure indicator target.

• Never use arm traction. Do not have staff pull the arms or shoulders. Do not raise an arm for a swimmer's projection when shoulder, clavicle, spinal or upper-limb injury may exist. Any additional maneuver requires explicit clinical approval and sufficient trained personnel.
• An incomplete view does not clear the spine. If C7-T1 or other required anatomy is absent, label the limitation and follow the radiologist/trauma protocol—usually CT rather than repeated forceful positioning.
• Do not diagnose from a positioning checklist. Prevertebral soft-tissue thickness varies with level, age, respiration and technique. Alignment and soft tissues require interpretation in clinical context.

Portable AP Chest in Trauma

Acquisition

• Position: Keep an unstable or motion-restricted patient supine. Elevate the torso only when the trauma team approves it. Sliding a detector behind the patient must be coordinated; do not independently lift or roll the torso.
• Beam: A routine supine AP chest normally uses an AP beam perpendicular to the detector—not a horizontal beam. Center and angle according to detector position and local mobile-chest protocol.
• Coverage: Include both apices, both lateral lungs and both costophrenic regions. Record supine, semierect or erect position because it changes interpretation.
• Respiration: Expose on inspiration when feasible. Coordinate an inspiratory pause with the person controlling ventilation; the radiographer must not independently alter ventilation.
• Technique: Use the validated equipment-specific chart, appropriate grid decision and shortest practical exposure time. There is no safe universal kVp/mAs recipe across mobile systems and patient sizes.

Interpretive Limits That Affect Technique

• Pneumothorax: In a supine patient, pleural air may collect anteriorly and basally; a deep sulcus can be a sign, but a normal film does not exclude pneumothorax. eFAST or CT is more sensitive.
• Hemothorax: Supine pleural blood may layer posteriorly and produce diffuse increased opacity rather than classic erect costophrenic blunting.
• Aortic injury: AP magnification, rotation and low inspiration can widen the mediastinum. An “8 cm” cutoff is not a reliable diagnosis or exclusion rule; suspected blunt aortic injury requires definitive CT angiographic evaluation when appropriate.
• Pulmonary contusion: Opacity may be present early or evolve over hours; CT is more sensitive. Do not delay care or schedule an automatic repeat solely because an early film is negative.

Portable AP Pelvis in Trauma

Major pelvic-ring disruption can be associated with severe hemorrhage. A portable AP pelvis is useful when its result can immediately affect management; stable patients may instead have pelvic assessment as part of CT under local protocol.

Safe Acquisition

• Movement: Keep the patient supine and aligned. Coordinate placement of a detector that is not already beneath the patient using the trauma team's approved lift/transfer method; do not independently roll or lift a suspected unstable pelvis.
• Legs: Leave the lower limbs neutral when hip, proximal-femur or pelvic injury is suspected. Do not internally rotate, abduct or pull a painful/deformed limb merely to reproduce routine positioning.
• Coverage: Include the iliac crests, entire pelvic ring, both hips and proximal femora through at least the lesser trochanters, unless a larger field or additional femur images are prescribed locally.
• Center/technique: Center to the midline pelvis using the facility positioning and exposure chart. Assess rotation and coverage, but do not force correction when movement is unsafe.
• Binder: Do not remove, loosen or reposition a pelvic binder for imaging unless the treating clinician directs it. Binder application and placement are clinical treatment decisions.

Horizontal-Beam and Decubitus Terminology

A horizontal beam is level with the floor and usually meets a vertical detector. It can provide an orthogonal view while the injured body part remains supported. It does not by itself define the patient position.

Suspected Pneumoperitoneum

CT is much more sensitive and identifies the cause and associated injury. If CT is unavailable and radiography is requested, an erect chest/abdomen or left lateral decubitus abdomen can show free subdiaphragmatic or right-sided gas—but only if the patient can safely assume that position. A dorsal decubitus horizontal-beam lateral can be used without rolling, with lower sensitivity. Do not roll a motion-restricted trauma patient merely to wait 5–10 minutes for a decubitus image.

Trauma Imaging by Body Region

Thoracic and Lumbar Spine

Do not wait for “C-spine clearance” as a prerequisite to assess another suspected spinal level, and do not flex the knees or torso in a motion-restricted patient. For adults who are high risk or cannot be examined, ACR rates CT of the thoracic/lumbar area without contrast “Usually Appropriate” and radiography “Usually Not Appropriate.” If radiographs are specifically ordered because CT is unavailable, obtain AP and horizontal-beam lateral views without moving the spine and document limitations.

Extremities, Open Injury and Foreign Bodies

• Support first: Do not straighten, rotate or manipulate a suspected fracture/dislocation. Leave splints and dressings unless an authorized clinician directs removal; never disturb hemorrhage control or a sterile field for positioning.
• Views: Obtain at least two substantially orthogonal projections when safely possible. For a long-bone injury, include the adjacent joints according to the requested exam/local protocol; a focused joint injury may require a dedicated joint series. If a view is unsafe, document why rather than forcing it.
• Penetrating injury: Never remove an impaled object. A radiopaque wound marker may be used only when local protocol requests it, it can be placed without delaying care or contaminating a wound, and it cannot be mistaken for a retained object. Do not infer a three-dimensional projectile path from two skin markers alone.
• Foreign-body detection: Radiographs depict many metallic, glass and mineral objects but may miss wood, plastic and other radiolucent material. Ultrasound or CT may be needed; a negative radiograph does not exclude a foreign body.

Head and Face

For adult major blunt trauma with suspected facial injury, ACR rates CT maxillofacial without contrast and CT head without contrast as appropriate initial tests. Plain skull/facial series should not delay CT and should be reserved for an explicit local indication or when CT is unavailable. Do not rotate or extend a motion-restricted neck to create Waters, Caldwell or Towne positions.

Exposure, Image Quality and Repeats

Digital detector response, generator output, filtration, grid design, source-to-image distance and patient size vary, so fixed internet technique ranges are not transferable. Follow the validated technique chart and diagnostic reference/quality-control program for that unit.

• Collimation: Include all clinically required anatomy while restricting the field to reduce scatter and avoid needless exposure.
• Grid/AEC: Use a grid only when the chart calls for it and alignment can be achieved. AEC can fail when the selected chamber is not fully covered by the intended anatomy or is covered by high-attenuation hardware; select manual or AEC technique according to protocol.
• Motion: Choose the shortest practical exposure time consistent with adequate receptor exposure. Do not increase mA beyond equipment limits or trade away required penetration.
• Exposure indicator: Review the manufacturer-specific indicator and the anatomy—not image brightness alone—to detect under- or overexposure.
• Repeat decision: Do not repeat automatically for minor rotation, a target-exposure-indicator miss or cosmetic imperfection. Repeat only when missing information is clinically important, after correcting the cause, and under departmental authorization/escalation policy. Document a deliberately limited image when positioning was unsafe.

Radiation Safety and Pregnancy

• Staff: Clear nonessential people before exposure. Use a structural/mobile barrier when available; otherwise maximize distance and avoid the primary beam. Required protective apparel and personal monitoring are set by the employer, radiation-safety program and applicable regulation—not by ARRT certification. Wear dosimeters in the location specified by that program.
• Patient shielding: Routine gonadal/fetal contact shielding is not recommended by AAPM because it offers negligible benefit against internal scatter and can obscure anatomy, interfere with AEC and cause repeats. Follow the facility's current policy.
• Pregnancy screening: Ask and document pregnancy status when feasible before examinations that may directly expose the uterus, following local policy. Do not let screening delay emergency imaging needed to diagnose serious maternal injury. FDA notes that the risk of not performing a needed X-ray may be greater than its radiation risk; ACR rates a trauma radiographic series “Usually Appropriate” even in the stable pregnant major-blunt-trauma variant.
• Optimization: Use the needed examination, correct protocol, accurate collimation and planned positioning. If pregnancy is known, notify the radiologist/authorized clinician so the examination can be justified and optimized; do not cancel it independently.

Communication and Workflow

1. Confirm the order/clinical question and identify the patient with two approved identifiers (or the emergency-identification process).
2. Ask the trauma leader which immediate adjuncts are required and whether any movement restriction, unstable limb, binder, lines or sterile procedures change detector placement.
3. Prepare the detector and technique before approaching the patient. Coordinate every lift, roll, torso elevation, limb move or ventilator pause with the responsible team member.
4. Announce the exposure, clear nonessential people, use distance/barriers, and expose without delaying resuscitation.
5. Check identity, laterality, position label, coverage, motion, exposure indicator and clinically important device visibility. Escalate rather than independently repeating or obtaining unrequested views.
6. Transmit promptly and document nonstandard position, retained splint/binder, limited anatomy and the reason. Communicate urgent technical problems or observations through the facility's approved escalation pathway; image interpretation belongs to qualified clinicians.
7. Use a trained team and approved transfer device for CT. The radiographer should not independently move a motion-restricted or hemodynamically unstable patient.

Common Pitfalls

• Calling a lateral C-spine a clearance film: adult clearance is clinical in validated low-risk patients or CT-based when imaging is indicated.
• Confusing AP with horizontal beam: a supine AP chest generally uses an AP beam perpendicular to the detector; “dorsal decubitus” is a separate lateral projection.
• Forcing textbook position: never pull arms, rotate legs, flex knees or roll a suspected spine/pelvis/hip/long-bone injury simply to improve appearance.
• Overreading a portable chest: supine AP technique can hide pleural air/fluid and exaggerate the mediastinum; it cannot exclude aortic injury.
• Unnecessary repeats: determine whether the existing image answers the question and escalate before adding dose or delaying care.

Authoritative Sources and Protocol Scope

This article distinguishes national guidance from local implementation. Exact trauma-series composition, order, detector placement, exposure chart, repeat authorization, pregnancy screening and staff monitoring remain facility- and jurisdiction-specific.

• ACR Appropriateness Criteria: Acute Spinal Trauma (revised 2024) — clinical-rule variants; CT versus radiography; thoracolumbar imaging.
• ACR Appropriateness Criteria: Major Blunt Trauma (revised 2025) — unstable/stable and pregnant variants, trauma radiography and CT.
• ACS TQIP Best Practices Guidelines: Spine Injury — motion restriction, clinical clearance and CT-based adult clearance.
• ACS TQIP Best Practices Guidelines in Imaging — chest/pelvis adjuncts, FAST and CT workflow.
• AAPM Position Statement on Patient Gonadal and Fetal Shielding — routine contact shielding should be discontinued.
• IAEA: Radiation protection of medical staff — time, distance, shielding and workplace radiation protection.
• US NRC 10 CFR 20.1502: Conditions requiring individual monitoring — US monitoring thresholds; other jurisdictions differ.
• FDA: X-Rays, Pregnancy and You — justification and the risk of withholding needed imaging.
• The accuracy of plain radiography in detection of traumatic intrathoracic injuries — limits of supine chest radiography compared with CT.
• CT imaging of blunt chest trauma — pneumothorax, hemothorax, contusion and aortic-injury imaging.
• Imaging of foreign bodies: a radiological conundrum — material-dependent radiographic visibility and roles of ultrasound/CT.