What are the typical MRI findings and treatment options for snapping hip syndrome?

MRI Findings for Snapping Hip Syndrome

MRI is the preferred imaging modality after initial radiographs for diagnosing snapping hip syndrome (coxa sultans), revealing both anatomical abnormalities and secondary signs of the condition. 1

Diagnostic Imaging Pathway

1. Initial Radiographs

   • First-line imaging to exclude other causes of hip pain
   • May appear normal or show minimal findings in snapping hip syndrome
   • Helps rule out osteoarthritis, calcified bodies, or stress fractures

2. MRI Without Contrast

   • Highly sensitive and specific for detecting soft tissue abnormalities
   • Should be the first advanced imaging technique after radiographs 1
   • Can identify:
     • Iliopsoas or subiliacus bursitis
     • Tendinosis or tears of hip muscles
     • Secondary signs suggesting snapping hip syndrome

3. Dynamic Ultrasound

   • Useful for real-time evaluation of tendon translation during hip movement
   • Can directly visualize the snapping phenomenon
   • Non-invasive alternative to fluoroscopic evaluation 1
   • Particularly valuable for evaluating external snapping (iliotibial band) and internal snapping (iliopsoas tendon) 2

Typical MRI Findings

Internal Snapping Hip (Iliopsoas Tendon)

• Thickening of the iliopsoas tendon (tendinitis) 2
• Peritendinous fluid collection
• Iliopsoas bursitis
• Normal intra-articular structures (helps exclude other pathologies) 2

External Snapping Hip (Iliotibial Band)

• Thickening of the iliotibial band
• Inflammation around the greater trochanter
• Trochanteric bursitis

Treatment Options

1. Conservative Management (First-Line)

   • Structured 6-12 week physiotherapist-led rehabilitation program 3
   • Focus on:
     • Hip flexor stretching (primary focus for iliopsoas-related snapping) 4
     • Core strengthening
     • Hip girdle muscle strengthening
     • Activity modification
   • Pain management:
     • Paracetamol (up to 4g/day) as first-line analgesic 3
     • Short-term NSAIDs if paracetamol is insufficient
     • Opioids only when other options are contraindicated or ineffective

2. Injection Therapy

   • Diagnostic and therapeutic injections can confirm the location of pain and provide short-term relief 1
   • Trochanteric and iliopsoas bursal or peritendinous injections may be useful 1

3. Surgical Management (for Refractory Cases)

   • Consider if symptoms persist after 3-6 months of appropriate conservative management 5
   • Options include:
     • Arthroscopic release of the iliopsoas tendon (for internal snapping)
     • Lengthening of the iliotibial band (for external snapping)
     • Addressing any concomitant labral pathology if present

Clinical Pearls and Pitfalls

• Most cases of snapping hip syndrome resolve with 6-12 months of conservative management 5
• Dynamic ultrasound is particularly valuable for confirming the diagnosis by directly visualizing the snapping tendon in real-time 6
• Snapping hip syndrome can be misdiagnosed or confused with intra-articular pathologies; MRI helps exclude other conditions 6
• Premature surgical intervention should be avoided without completing a full conservative management program 3
• Incidental findings on MRI should be correlated with clinical symptoms, as asymptomatic labral tears are common 3

Follow-up Recommendations

• Regular assessment of pain levels and functional improvement during conservative treatment
• Consider advanced imaging and surgical consultation if symptoms persist despite 3 months of appropriate management 3
• Annual follow-up to monitor for progression of symptoms or development of early osteoarthritis