Should an MRI of the right foot and right hip be done with or without contrast?

MRI of the Right Foot and Hip Should Be Performed Without Contrast

For both the right foot and right hip MRI, imaging should be performed without contrast unless there is specific concern for infection or tumor. According to the ACR Appropriateness Criteria, MRI without IV contrast is the recommended approach for most musculoskeletal conditions affecting the hip and foot 1.

Hip MRI Protocol

When to Use MRI Without Contrast:

• Suspected labral tear
• Suspected tendinopathy or bursitis
• Evaluation of bone marrow edema
• Suspected stress fracture or occult fracture
• Osteonecrosis evaluation
• Muscle or ligament injury
• Femoroacetabular impingement

MRI without contrast has excellent sensitivity for detecting most hip pathologies. The ACR Appropriateness Criteria for Chronic Hip Pain specifically states that "IV contrast is rarely needed for MRI" of the hip 1. For suspected osteonecrosis, MRI without contrast is the imaging study of choice after radiographs 1.

When to Consider Adding Contrast:

• Suspected infection (septic arthritis, osteomyelitis)
• Suspected inflammatory arthritis requiring synovitis evaluation
• Suspected tumor
• Need to differentiate between joint fluid and synovitis

Foot MRI Protocol

When to Use MRI Without Contrast:

• Suspected stress fracture
• Tendon or ligament injury
• Osteochondral lesions
• Bone contusion or occult fracture
• Plantar fasciitis
• Tarsal coalition

For foot imaging, non-contrast MRI provides excellent visualization of bone marrow, tendons, ligaments, and other soft tissue structures 2, 3.

When to Consider Adding Contrast:

• Suspected infection
• Suspected tumor
• Need to evaluate for synovitis

Clinical Decision Algorithm

1. Start with radiographs as the initial imaging modality for both hip and foot pain
2. Proceed to MRI without contrast if:
   • Radiographs are negative but symptoms persist
   • Need to evaluate soft tissue structures
   • Need to assess for occult fracture
   • Need to evaluate for osteonecrosis
3. Add contrast only if:
   • Infection is suspected (fever, elevated inflammatory markers)
   • Tumor is suspected (night pain, weight loss, constitutional symptoms)
   • Need to differentiate joint fluid from synovitis

Important Considerations

• MRI without contrast is highly sensitive for detecting most musculoskeletal pathologies and should be the default choice 1
• Adding contrast increases cost, procedure time, and potential risks without significantly improving diagnostic yield for most common conditions
• For suspected occult hip fracture, MRI without contrast has nearly 100% sensitivity, making it superior to CT or bone scan 1, 4
• For foot imaging, non-contrast MRI provides excellent visualization of bone marrow, tendons, ligaments, and other soft tissue structures 2, 3

Common Pitfalls to Avoid

• Ordering contrast unnecessarily for routine musculoskeletal conditions
• Failing to obtain appropriate clinical history to guide protocol selection
• Ordering MRI before appropriate radiographs have been obtained
• Assuming that contrast always improves diagnostic yield (it often doesn't for most musculoskeletal conditions)

In conclusion, based on the ACR Appropriateness Criteria and current evidence, both the right foot and right hip MRI should be performed without contrast unless there are specific clinical concerns for infection or tumor.