For hip pain, should I obtain an MRI or a CT scan?

MRI is the Preferred Imaging Modality for Hip Pain After Initial Radiographs

For hip pain evaluation, obtain plain radiographs first, then proceed to MRI without IV contrast as the next imaging study—MRI should generally be the first advanced imaging technique used after radiographs for most hip pain scenarios. 1

Algorithmic Approach to Hip Pain Imaging

Step 1: Always Start with Plain Radiographs

• Obtain AP pelvis view plus dedicated hip views (AP with 15° internal rotation and cross-table lateral) 1
• Radiographs may be sufficient for common conditions like osteoarthritis or bone tumors
• Even when negative, radiographs guide selection of subsequent imaging 1

Step 2: When Radiographs Are Negative, Equivocal, or Non-Diagnostic

Choose MRI (without IV contrast) when suspecting:

• Soft tissue pathology (tendonitis, bursitis, muscle/tendon tears, labral tears) 1
• Intra-articular pathology (labral tears, cartilage defects, loose bodies) 1
• Occult fractures (stress fractures, bone marrow edema)
• Osteonecrosis (MRI is most sensitive) 2
• Tumors (best for intramedullary and soft tissue extent) 2
• Inflammatory conditions (synovitis, bursitis) 1

MRI advantages:

• Highly sensitive and specific for osseous and soft tissue abnormalities 1
• No ionizing radiation
• Superior soft tissue contrast
• Detects bone marrow edema and early pathology
• Can evaluate cartilage, labrum, tendons, and surrounding structures simultaneously

Step 3: Limited Role for CT in Non-Traumatic Hip Pain

CT is generally NOT the preferred modality for chronic hip pain 1

CT has specific but limited indications:

• Computer-navigated surgery planning (rated 9/9 appropriateness) 1
• When MRI is contraindicated (pacemakers, certain implants, severe claustrophobia)
• Detailed bony anatomy assessment (complex fracture patterns, surgical planning)
• CT is less sensitive for soft tissue evaluation 1

Important Clinical Context: Trauma vs. Non-Trauma

For ACUTE TRAUMATIC Hip Pain:

The algorithm differs—radiographs remain first-line, but if occult fracture is suspected:

• CT can be used as first advanced imaging (faster, more accessible) 3, 4, 5
• Modern CT rarely misses clinically significant fractures 4
• CT reduces ED time (430 vs 502 minutes for MRI) 3
• If CT is negative but clinical suspicion remains high, then obtain MRI 6, 5

For CHRONIC/NON-TRAUMATIC Hip Pain:

• MRI without IV contrast is the clear first choice after radiographs 1
• IV contrast is rarely needed for MRI 1
• Consider MR arthrography or CT arthrography specifically for suspected labral tears with impingement 1

Common Pitfalls to Avoid

1. Don't skip radiographs: Always obtain plain films first—they're fast, inexpensive, and may be diagnostic 1

2. Don't default to CT for non-traumatic pain: CT has significantly lower soft tissue sensitivity and exposes patients to radiation 1

3. Don't order IV contrast routinely: MRI without contrast is sufficient for most hip pathology 1

4. Don't forget ultrasound for specific indications: US is excellent for superficial structures (trochanteric bursitis, abductor tendon pathology) and can guide injections 1

5. Consider patient-specific factors: 26% of elderly patients have MRI contraindications 3—in these cases, CT becomes the alternative

Evidence Quality Considerations

The ACR Appropriateness Criteria (2017) represents the highest quality guideline evidence available, based on systematic review of 107 references including multiple good-quality studies [1-1]. This guideline explicitly states that "MRI should, in general, be the first imaging technique used after radiographs" for detecting osseous and soft tissue abnormalities in chronic hip pain 1.

The research comparing CT vs MRI for occult fractures [3-7] shows mixed results, but these studies focus on acute trauma scenarios, not the broader question of chronic hip pain evaluation where MRI's soft tissue superiority becomes critical for diagnosis and treatment planning.