What are the recommended tests and treatment options for a patient presenting with shoulder pain or discomfort, considering their medical history and potential underlying conditions such as diabetes or rheumatoid arthritis?

Recommended Tests for Shoulder Pain

Begin with standard radiographs (anteroposterior views in internal and external rotation, plus axillary or scapula-Y view) as the initial imaging study for any patient presenting with shoulder pain, then advance to MRI without contrast or ultrasound for suspected rotator cuff pathology, or CT for fracture characterization. 1

Initial Imaging Approach

• Radiography is the mandatory first-line imaging study for acute shoulder pain regardless of etiology 1
• Standard views must include anteroposterior projections in both internal and external rotation, plus either axillary or scapula-Y view to adequately assess the glenohumeral joint and identify fractures or dislocations 1, 2
• Plain radiographs can identify massive rotator cuff tears, shoulder instability, glenohumeral or acromioclavicular osteoarthritis, and obvious fractures 3

Advanced Imaging Based on Clinical Presentation

For Suspected Occult Fracture (Normal or Nonspecific Radiographs)

• CT without IV contrast is the preferred study for detailed osseous evaluation with high spatial resolution to identify subtle nondisplaced fractures 1
• MRI without contrast is an equivalent alternative that demonstrates bone marrow edema from trauma and identifies associated soft tissue injuries (rotator cuff or labral tears) 1

For Confirmed Fractures on Radiographs

• CT without IV contrast is superior for characterizing complex fracture patterns and surgical planning for proximal humerus, scapular, or clavicle fractures 1
• MRI without contrast may be appropriate only when assessing possible rotator cuff injury in patients not planned for surgical fracture fixation 1

For Suspected Rotator Cuff Pathology

• MRI without contrast or ultrasound are equivalent first-line studies after noncontributory radiographs—only one needs to be ordered 1, 2
• MRI is preferred when: large body habitus limits ultrasound visualization, restricted range of motion prevents adequate ultrasound positioning, or suspicion exists for additional intraarticular pathology like labral tears 1
• Ultrasound is preferred when: previous proximal humeral hardware creates MRI susceptibility artifacts, or local expertise in musculoskeletal ultrasound is available 1
• Clinical decision rule supporting rotator cuff tear diagnosis includes: pain with overhead activity, weakness on empty can and external rotation tests, and positive impingement sign 3

For Suspected Labral Tear or Instability

• MRI without contrast is the primary study for acute dislocation or instability, as posttraumatic joint effusion or hemarthrosis provides sufficient visualization of soft tissue structures 1
• MR arthrography is appropriate for detailed labral evaluation in subacute or chronic settings when joint effusion is insufficient for adequate distention 1
• For patients under 35 years with instability or questionable labral pathology, MRI or MR arthrography are the modalities of choice 2
• CT arthrography is appropriate only when MRI is contraindicated 1
• Positive apprehension and relocation tests on physical examination support the diagnosis of glenohumeral instability 3

Special Clinical Scenarios

Post-Stroke Hemiplegic Shoulder Pain

• Ultrasound may be considered as a diagnostic tool for shoulder soft tissue injury in this population 1
• Clinical assessment should include musculoskeletal evaluation, spasticity assessment, identification of subluxation, and testing for regional sensory changes 1

Suspected Referred Pain

• Do not image the shoulder when clinical examination suggests referred pain—imaging should target the suspected source 4
• Consider pulmonary pathology when shoulder pain clusters with thoracic pain, coughing, shortness of breath, fever, and fatigue 5
• Standard shoulder treatments will fail because the pathology is not in the shoulder 4

Critical Examination Components Before Imaging

• Assess both active and passive range of motion: forward flexion (0-180°), external rotation (0-90°), and internal rotation (ability to reach up back) 2
• Test rotator cuff muscles individually: supraspinatus (empty can test), infraspinatus/teres minor (external rotation), subscapularis (lift-off test, belly press test) 2
• Palpate acromioclavicular joint, sternoclavicular joint, bicipital groove, and identify areas of swelling, warmth, or crepitus 2
• Evaluate for scapular dyskinesis which may contribute to rotator cuff injury 2
• For patients with diabetes or thyroid disorders, consider adhesive capsulitis presenting as diffuse shoulder pain with restricted passive range of motion 3

Common Pitfalls to Avoid

• Do not order MR arthrography in acute trauma settings—the natural joint effusion eliminates the need for contrast injection 1
• Do not rely on MRI to characterize complex fracture patterns—CT is superior for this purpose 1
• Do not assume shoulder pathology without considering referred pain from cervical spine, cardiac, pulmonary, or abdominal sources 4, 5
• Recognize that imaging abnormalities may not be symptomatic—correlate clinical assessment with imaging findings rather than treating images alone 6