What is the algorithm for assessing acute shoulder pain?

Algorithm for Assessment of Acute Shoulder Pain

The initial assessment of acute shoulder pain should begin with standard radiographs, including anteroposterior views in internal and external rotation, and axillary or scapula-Y view, as these are usually appropriate for evaluating fractures, dislocations, and shoulder alignment. 1, 2

Initial Evaluation

History

• Mechanism of injury (fall, direct trauma, sports-related)
• Location and quality of pain (anterior, posterior, lateral)
• Onset and duration of symptoms
• Aggravating and alleviating factors
• Previous shoulder injuries or treatments
• Functional limitations

Physical Examination

1. Inspection:

   • Shoulder contour and symmetry
   • Muscle atrophy
   • Swelling or ecchymosis

2. Palpation:

   • Acromioclavicular joint
   • Sternoclavicular joint
   • Bicipital groove
   • Greater tuberosity
   • Subacromial space

3. Range of Motion Assessment:

   • Active and passive motion
   • Forward flexion, abduction, internal/external rotation
   • Scapular movement

4. Special Tests:

   • For instability: apprehension test, relocation test
   • For impingement: Neer test, Hawkins-Kennedy test
   • For rotator cuff: empty can test, drop arm test
   • For labral tears: O'Brien's test, crank test

Diagnostic Imaging Algorithm

Step 1: Initial Radiographs

• Standard radiographs (AP views in internal/external rotation, axillary or scapula-Y view) 1
• Evaluate for fractures, dislocations, and proper alignment

Step 2: Advanced Imaging Based on Clinical Suspicion

For Suspected Occult Fracture with Normal Radiographs:

• CT shoulder without IV contrast OR
• MRI shoulder without IV contrast 1

For Confirmed Proximal Humerus, Scapular, or Clavicle Fracture:

• CT shoulder without IV contrast 1
• Consider MRI without contrast if rotator cuff injury is suspected and surgical fixation is not planned

For Suspected Dislocation or Instability:

• MRI shoulder without IV contrast 1
• Consider CT shoulder without IV contrast if bone loss assessment is needed

For Suspected Labral Tear:

• MRI shoulder without IV contrast (acute setting with effusion) OR
• MR arthrography (subacute/chronic setting) OR
• CT arthrography (if MRI contraindicated) 1, 2

For Suspected Rotator Cuff Tear:

• MRI shoulder without IV contrast OR
• Ultrasound of the shoulder 1, 2
  • MRI preferred for large body habitus, restricted motion, or suspicion of other intra-articular pathologies

Treatment Approach

Initial Management

1. Pain Control:

   • NSAIDs (e.g., naproxen 500mg initially, then 500mg every 12 hours) 2, 3
   • Local cold therapy for pain relief 2
   • Consider sling for comfort in acute phase 4

2. Early Rehabilitation (Phase 1):

   • Pain control measures
   • Gentle range of motion exercises
   • Proper positioning education
   • Isometric exercises if pain-free 2

Follow-up Plan

• Initial follow-up: 1-2 weeks after treatment initiation 2
• Clinical reassessment: 6 weeks to evaluate progress 2
• Consider advanced imaging or surgical consultation if:
  • Symptoms worsen
  • No improvement after 3 months of appropriate rehabilitation
  • Patient is under 30 years with high athletic demands
  • Evidence of significant mechanical symptoms 2

Special Considerations

• Urgent Surgical Referral is indicated for:

  • Posterior sternoclavicular dislocations 4
  • Types IV, V, and VI acromioclavicular joint injuries 4
  • Displaced or unstable proximal humerus fractures 4

• Surgical Consultation may be considered for:

  • Middle third clavicle fractures in active individuals 4
  • Type III acromioclavicular sprains in active individuals 4
  • First-time glenohumeral dislocation in young athletes 4
  • Full-thickness rotator cuff tears 4

• Medication Cautions:

  • Lower NSAID doses for elderly patients and those with renal/hepatic impairment 3
  • Limit corticosteroid injections (no more than 3-4 per year) to avoid tendon weakening 2

Common Pitfalls to Avoid

• Relying solely on imaging findings without clinical correlation
• Failing to evaluate the neck and elbow which may refer pain to the shoulder
• Overlooking psychosocial factors that may influence pain perception and recovery
• Delaying appropriate referral for conditions requiring surgical management
• Excessive use of corticosteroid injections which can lead to tendon weakening

By following this structured approach to assessment and management, clinicians can effectively diagnose and treat acute shoulder pain while optimizing patient outcomes.