What is the next step in diagnosing hip pain?

Diagnostic Approach to Hip Pain

The next step in diagnosing hip pain should be plain radiographs, specifically anteroposterior (AP) pelvis and lateral femoral head-neck view radiographs, as these provide essential baseline information about bone morphology, joint space, and potential degenerative changes. 1, 2

Initial Imaging Approach

Plain Radiographs

• First-line imaging test for most cases of hip pain 2
• Required views:
  • Anteroposterior (AP) view of the pelvis
  • Lateral femoral head-neck view (options include: Dunn view, frog-leg/Lauenstein view, or cross-table lateral) 1
• Rationale: Provides understanding of underlying hip morphology and screens for common disorders such as arthritis, fractures, or bone tumors 1

Clinical Value of Radiographs

• Can identify obvious pathology that may be the sole cause of pain (e.g., osteoarthritis, advanced osteonecrosis)
• May be the only imaging necessary for many common conditions 1
• Helps screen for potential serious conditions requiring urgent intervention

Advanced Imaging (When Indicated)

If radiographs are negative or equivocal but clinical suspicion remains high:

MRI Without Contrast

• Second-line imaging when radiographs are inconclusive 2
• Benefits:
  • Highly sensitive for detecting occult fractures, avascular necrosis, bone marrow edema
  • Can identify soft tissue pathologies not visible on radiographs 2
  • Valuable for evaluating labral tears, cartilage damage, and ligamentum teres conditions 1

MR Arthrography

• Specific indication: When labral tears are suspected 3
• Provides better visualization of intra-articular structures

CT Scan

• Indication: When three-dimensional morphological assessment is needed 1
• Useful for complex bony anatomy evaluation 1

Diagnostic Categorization

After imaging, hip pain can be further categorized into:

1. Femoroacetabular impingement (FAI) syndrome
2. Acetabular dysplasia and/or hip instability
3. Other conditions causing hip-related pain (including soft tissue conditions without specific bony morphology) 1

Important Clinical Considerations

Location-Based Assessment

• Anterior hip pain: Often indicates intra-articular pathology (labral tears, FAI, osteoarthritis) 3
• Lateral hip pain: Commonly associated with greater trochanteric pain syndrome 3
• Posterior hip pain: May indicate piriformis syndrome, sacroiliac joint dysfunction, or lumbar radiculopathy 3

Diagnostic Pitfalls to Avoid

• Never rely solely on imaging for diagnosis; always correlate with clinical findings 1
• Don't skip radiographs and proceed directly to advanced imaging 2
• Don't attribute pain solely to age without thorough evaluation 2
• Remember that pain may be referred from lumbar spine, sacroiliac joints, or knee 1

Special Diagnostic Considerations

• FADIR test (flexion, adduction, internal rotation) can help rule out hip-related pain, though it has limited diagnostic accuracy 1
• Consider diagnostic injections when the source of pain remains unclear 3
• Remember that many hip conditions—especially labral and chondral conditions—coexist with FAI syndrome and acetabular dysplasia 1

Following this systematic approach to diagnosing hip pain ensures appropriate evaluation while minimizing unnecessary testing and potential delays in diagnosis and treatment.