CT Extremity (Upper or Lower) — Dictation, Appropriateness, and Dose for Residents

1. That Call from Ortho Is Coming

Stat from the ED. Polytrauma, and the ortho resident is already on the phone asking for the Schatzker class on that tibial plateau fracture. You see the comminution, the articular depression, and the subtle signs of a meniscal injury, but you know your attending expects a perfect, structured report that quantifies everything. Getting the classification right is table stakes; communicating it clearly and quickly is how you build trust.

When I was a resident, these were the reads that could make or break a shift. The anatomy is complex, the fracture classifications are numerous, and the surgical implications are immediate. This guide is built for those moments. It’s a framework for dictating CT extremity studies for trauma, hardware evaluation, or tumor, designed to be fast, accurate, and attending-proof. We’ll cover the core template, key classifications to have at your fingertips, and when this study is the right call. For more tools like this, check out the residents and fellows resource hub.

2. What a CT Extremity Study Covers and What Attendings Look For

A CT of the upper or lower extremity is the workhorse for detailed bone evaluation, especially when plain films are negative or insufficient. It excels at defining fracture anatomy for pre-operative planning and assessing post-operative hardware. While MRI is king for soft tissues, CT provides unparalleled detail for cortical and trabecular bone.

Your attending expects a report that definitively answers these key clinical questions:

• Fracture Detail: Is there an occult fracture not seen on radiographs? How comminuted is it? Is there intra-articular extension and, if so, what is the degree of displacement and articular surface depression?
• Specific Classifications: Does the fracture fit a standard surgical classification system (e.g., Schatzker for tibial plateau, Sanders for calcaneus, Letournel for acetabulum)?
• Pre-operative Planning: Are the 3D reformats sufficient for the surgical team to plan their approach and hardware placement?
• Hardware Evaluation: Is the existing hardware correctly positioned? Are there signs of loosening (lucency), hardware failure (fragmentation), or periprosthetic fracture?
• Tumor Characterization: Is there evidence of cortical destruction, a soft tissue mass, or a pathologic fracture?

3. Radiology Report Template for CT Extremity (Upper or Lower)

This template provides a solid starting point. Modify the “Findings” section based on the specific anatomy and pathology. The “Impression” is where you synthesize the key findings into a clinically actionable summary.

Technique

Helical CT images of the [right/left] [knee/ankle/foot/wrist/hand/hip] were acquired without intravenous contrast. Axial, coronal, and sagittal reformations were created using bone and soft tissue algorithms. 3D volumetric reconstructions were also performed.

Findings

Bones: Evaluate for fracture, dislocation, or subluxation. Describe fracture lines, comminution, displacement, angulation, and intra-articular extension.

Example (Tibial Plateau): Comminuted fracture of the [medial/lateral] tibial plateau, consistent with a Schatzker type [I-VI] injury. There is approximately [X] mm of articular surface depression.

Example (Calcaneus): Comminuted intra-articular fracture of the calcaneus. The posterior facet is depressed, with a Boehler’s angle of [X] degrees. Consistent with a Sanders type [I-IV] fracture.

Example (Lisfranc): Diastasis between the bases of the first and second metatarsals measuring [X] mm, concerning for a Lisfranc injury.

Joints: Evaluate for joint effusion, loose bodies, and alignment. Note any degenerative changes such as osteophytes or joint space narrowing.

Hardware (if present): Describe the type and location of orthopedic hardware. Evaluate for hardware integrity, position, and signs of loosening such as periprosthetic lucency. Assess for periprosthetic fracture.

Soft Tissues: Evaluate the visualized soft tissues for swelling, hematoma, or other abnormalities. Note that soft tissue detail is limited compared to MRI.

Impression

Example 1: Tibial Plateau Fracture

1. Comminuted, displaced fracture of the lateral tibial plateau with [X] mm of articular depression, consistent with a Schatzker type [II] fracture.
2. Moderate knee joint effusion.

Example 2: Occult Scaphoid Fracture

1. Nondisplaced fracture through the waist of the scaphoid, not visualized on prior radiographs.
2. No evidence of carpal dislocation or instability.

Example 3: Hardware Loosening

1. Status post open reduction and internal fixation of a distal femur fracture.
2. Circumferential lucency around the distal locking screws, concerning for hardware loosening. No acute periprosthetic fracture.

4. Free Template Sources from the Radiology Community

Building a personal library of templates is a key part of residency. Before you start from scratch, know that two great free repositories exist, curated by major radiology organizations. They are excellent sources for common and uncommon studies alike.

• RadReport.org: Maintained by the RSNA, this is a comprehensive library of peer-reviewed templates covering nearly every modality and subspecialty.
• Radiology Templates (AU): An excellent, clean resource maintained by Australian radiologists with a practical, user-friendly interface.

5. The Next-Level Move: AI-Assisted Structured Reporting

The friction in reporting isn’t just finding the words; it’s structuring them perfectly under pressure. Instead of toggling between your dictation window and a template file, you can dictate your positive findings in free form and have an AI tool handle the rest. GigHz Precision AI is designed for this exact workflow. You speak the key findings—”comminuted lateral tibial plateau fracture with 5 mm of depression”—and the platform generates a clean, structured report using pre-loaded ACR and SIR templates. It helps ensure that critical elements like classifications and measurements are consistently placed in the impression, making your reports clearer for clinicians and faster for you to finalize.

6. When Should You Order a CT Extremity Study? ACR Appropriateness Criteria

The American College of Radiology (ACR) provides evidence-based guidelines to help choose the right test for the right clinical scenario. For extremity trauma, the decision often hinges on the findings of initial radiographs.

Based on the ACR Appropriateness Criteria for Acute Trauma to the Knee, CT is Usually Appropriate for evaluating a tibial plateau fracture seen on radiographs to assess for additional injury and for pre-operative planning. For a suspected occult fracture after a fall or twisting injury when radiographs are negative, both CT and MRI are rated as Usually Appropriate.

For Acute Trauma to the Foot, CT is often the next step when radiographs are normal or equivocal but there is high clinical suspicion for a Lisfranc injury, tendon injury, or occult fracture; in this scenario, CT May Be Appropriate. It is also excellent for characterizing complex calcaneal fractures for surgical planning.

Finally, for Acute Hand and Wrist Trauma, CT is Usually Appropriate for evaluating a suspected occult scaphoid fracture when radiographs are negative, and for characterizing complex distal radius fractures to assess for intra-articular extension.

These criteria primarily guide initial imaging decisions. The choice of follow-up imaging depends on the specific clinical question after initial management.

7. How Much Radiation Does a CT Extremity Study Deliver?

Patients and referring providers are increasingly aware of radiation dose. Being able to contextualize it is a core competency. A targeted CT of an extremity is a relatively low-dose study compared to body imaging.

The estimated effective dose for a CT extremity is typically in the range of 0.5 to 3 mSv. The exact dose depends on the size of the body part and the specific institutional protocol. To put this in perspective, the ACR notes that this dose is significantly less than a CT of the abdomen or pelvis and is comparable to the amount of background radiation a person receives over several months to a year.

Dose reduction techniques, including automated exposure control and iterative reconstruction, are standard on modern scanners and help keep the dose as low as reasonably achievable (ALARA).

8. CT Extremity Imaging Protocol — Phases, Contrast, and Reconstructions

The power of CT extremity imaging comes from thin-slice acquisition and multiplanar reformats. The protocol is typically non-contrast unless there is a specific concern for a vascular injury, infection (abscess), or certain tumors.

The scan is a single helical acquisition through the targeted body part. The key is in the reconstructions, which provide the detail necessary for diagnosis and surgical planning. Bone algorithms are essential for fracture characterization, while soft tissue algorithms can help identify associated hematomas or effusions.

A common pitfall is inadequate field of view, which can clip relevant anatomy, or motion artifact, which can obscure fine fracture lines. Proper patient positioning and instruction are critical.

9. The 3-Months-Free Offer for Residents and Fellows

3+ months free for radiology residents and fellows

Look like a rockstar on your reports — dictate positive findings in free form, and the AI generates a structured report using ACR + SIR templates with the appropriate clinical decision support firing automatically. This is a tool built by physicians, for physicians-in-training, to help you report more clearly and confidently.

All we ask is feedback so we can keep improving the product for trainees. The signup is simple. No credit card, no long forms. Just provide the following three items:

1. Your PGY year (e.g., PGY-2, PGY-4)
2. Your training type (radiology residency or specific fellowship)
3. Your training program / hospital name

To get started, apply for the residents free-access program and reply to the application email with the information above. We’ll get you set up.

10. Frequently Asked Questions (FAQ)

Is GigHz Precision AI HIPAA-compliant?

Yes. The platform is designed for de-identified workflows by default. No patient-identifying information is required or stored, ensuring compliance with HIPAA privacy and security standards.

Do I need my hospital’s IT department to set this up?

No. GigHz Precision AI is a secure, browser-based tool. There is no software to install. It works on any modern computer, including the workstations in the reading room or your personal laptop or iPad at home.

How does this work with PowerScribe or other dictation systems?

It works alongside your existing system. You can dictate your findings, use the AI to structure the report, and then copy/paste the final, clean text directly into your PACS or EMR reporting field. It’s a workflow enhancement, not a replacement.

Can I customize the templates?

Yes. While the system comes pre-loaded with standard ACR and society-based templates, you can create, modify, and save your own templates to match your personal style or your institution’s specific requirements.

What happens after my residency or fellowship ends?

We offer continuity plans for graduating trainees who want to continue using the tool in their practice. The free access program is specifically for active residents and fellows.