What is the initial imaging study recommended for a patient presenting with shoulder pain when lifting their arm?

Initial Imaging Study for Shoulder Pain When Lifting Arm

Plain radiographs should be obtained as the initial imaging study for a patient presenting with shoulder pain when lifting their arm to rule out fractures and other bony abnormalities before proceeding with more advanced imaging. 1

Diagnostic Imaging Algorithm

1. Plain Radiographs (X-rays) - First Line

   • Should be the first imaging study performed
   • Helps rule out fractures, dislocations, and bony abnormalities
   • Can identify Hill-Sachs lesions, calcifications, and arthritic changes
   • Standard views typically include:
     • Anteroposterior view
     • Lateral view
     • Axillary view

2. Advanced Imaging - Second Line (if needed)

   • MRI without contrast

     • Highly effective (rated 7/9) with optimized imaging equipment
     • Excellent for evaluating soft tissue structures including rotator cuff, labrum, and biceps tendon
     • Indicated if symptoms persist despite conservative treatment or if a soft tissue injury is suspected despite negative X-rays 1

   • MR Arthrography

     • Gold standard for labral tears, especially in patients under 35 years
     • Sensitivity of 86-100% for labral pathology 1

   • CT Arthrography

     • Third choice option
     • Only if MRI is contraindicated
     • Comparable to MR arthrography for Bankart and Hill-Sachs lesions 1

   • Ultrasound

     • Limited role compared to MRI
     • Can be useful for evaluating rotator cuff and biceps tendon pathology
     • Less expensive and more readily available than MRI 1

Clinical Considerations

Pain when lifting the arm is a common presentation that may indicate several pathologies:

• Rotator cuff tendinopathy or tears
• Subacromial impingement
• Glenohumeral joint pathology
• Labral tears (particularly SLAP lesions)
• Acromioclavicular joint disorders

While clinical examination is crucial in diagnosing shoulder pathologies 2, imaging provides objective confirmation of the diagnosis and helps guide treatment decisions.

Important Caveats

• A negative MRI with positive clinical tests may still warrant further investigation, as clinical assessment has shown higher sensitivity than MRI for certain conditions like SLAP lesions (90% vs 60%) 2
• MRI without proper clinical context may lead to overdiagnosis of incidental findings
• Plain radiographs alone may miss soft tissue pathologies that are common causes of shoulder pain
• Follow-up imaging should be considered if symptoms worsen or do not improve with conservative treatment 1

Follow-up Recommendations

• Initial follow-up should occur 1-2 weeks after treatment initiation
• Clinical reassessment at 6 weeks to evaluate progress
• Consider advanced imaging or specialist referral if:
  • Patient is not improving with conservative measures
  • Pain worsens despite appropriate therapy
  • New symptoms develop during rehabilitation 1

Remember that while MRI is widely considered the imaging modality of choice for comprehensive shoulder evaluation 3, 4, plain radiographs remain the appropriate initial imaging study for patients presenting with shoulder pain when lifting their arm.