What is the appropriate initial evaluation and management for a patient presenting with left shoulder pain?

Initial Evaluation and Management of Left Shoulder Pain

Standard three-view radiography (AP internal rotation, AP external rotation, and axillary or scapula-Y view) performed upright is the mandatory first imaging study for any patient presenting with left shoulder pain, regardless of suspected etiology. 1, 2

Immediate History Priorities

Determine if the pain is traumatic or atraumatic, as this fundamentally alters your differential diagnosis and management pathway. 3

For Traumatic Presentations:

• Document the exact mechanism: height of fall, landing position, direct blow versus indirect force 3
• Time from injury to presentation and symptom evolution 3
• Any history of prior shoulder dislocations, fractures, or repairs 3

For All Presentations:

• Classify timing: acute (<2 weeks) versus chronic (>6 months) 3
• Pain location specificity:
  • Anterior = rotator cuff or biceps pathology 3
  • Superior = acromioclavicular joint disease 3
  • Scapular region = referred cervical spine or rotator cuff 3
• Any sensation of instability, "giving way," or subluxation events 3
• Screen for red flags: fever, constitutional symptoms suggesting septic arthritis 3
• Check radial and ulnar pulses immediately—absent pulse after trauma mandates urgent vascular imaging 3

Age-Stratified Physical Examination

Patients Under 35-40 Years:

Focus your examination on instability and labral pathology, as these are the predominant causes in this age group. 3

• Perform apprehension test (anterior instability) 3
• Perform posterior stress test 3
• Assess for labral pathology with dynamic maneuvers 3

Patients 35-40 Years and Older:

Prioritize rotator cuff disease, impingement syndrome, and degenerative changes, which dominate this demographic. 3

• Hawkins test (92% sensitive for impingement) 3
• Neer test (88% sensitive for impingement) 3
• Empty can test for supraspinatus pathology 3
• External rotation strength testing 3
• Assess passive range of motion—limited passive motion suggests adhesive capsulitis; preserved passive with weak active motion indicates rotator cuff tear 3
• Inspect for supraspinatus/infraspinatus atrophy 3

Universal Examination Elements:

• Palpate acromioclavicular joint, biceps tendon, and bony landmarks 4
• Document active and passive range of motion in all planes 4
• Perform cross-body adduction test for AC joint pathology 5
• Complete sensorimotor examination of the entire upper extremity 4
• Examine cervical spine and elbow to exclude referred pain 4

Mandatory Initial Imaging Protocol

Order standard three-view shoulder radiographs with the patient upright (never supine, as this underrepresents malalignment): 1, 2

1. AP view in internal rotation 1, 2
2. AP view in external rotation 1, 2
3. Axillary OR scapula-Y view 1, 2

Critical pitfall: AP views alone miss up to 50% of glenohumeral and acromioclavicular dislocations—the third orthogonal view is non-negotiable. 2

Additional Views for Specific Scenarios:

• Add Grashey view (30° posterior oblique) when instability or dislocation is suspected 3
• Add Stryker notch view to evaluate Hill-Sachs lesions 1

Immediate Management Based on Radiographic Findings

If Radiographs Show Unstable/Displaced Fracture or Dislocation:

Immediate orthopedic referral is mandatory—do not attempt conservative management. 3, 6

If Radiographs Are Normal or Show Stable Fracture:

For Patients <35 Years with Suspected Instability/Labral Pathology:

Order MR arthrography (not standard MRI)—this is the gold standard for capsulolabral structures and SLAP tears in this population. 3

For Patients ≥35 Years with Clinical Impingement Syndrome:

Refer directly to physical therapy without obtaining MRI, as 80% achieve full recovery with 3-6 months of conservative care. 3

• MRI is only indicated if:
  1. Symptoms persist after 3-6 months of adequate physical therapy 3
  2. Clinical suspicion for full-thickness rotator cuff tear (marked weakness) 3
  3. Surgical planning is needed 3

Ultrasound is equivalent to MRI for rotator cuff evaluation when performed by experienced operators (85% sensitivity, 90% specificity), and allows dynamic assessment during movement. 3

Initial Conservative Management Algorithm

For Rotator Cuff Tendinopathy/Impingement (Age ≥35):

1. Complete rest from aggravating activities until asymptomatic 3
2. NSAIDs for acute pain control 3
3. Physical therapy protocol:
   • Stretching and mobilization to improve range of motion, especially external rotation and abduction 3
   • Eccentric strengthening exercises once pain-free motion achieved 3
   • Scapular stabilizer strengthening 3
4. Avoid overhead pulley exercises—these worsen rotator cuff pathology 3
5. Consider intra-articular corticosteroid injection (triamcinolone) for severe cases 3
6. Return to activities after 1-3 months of progressive rehabilitation without symptoms 3

For Adhesive Capsulitis:

• Aggressive stretching and mobilization focusing on external rotation and abduction 3
• Serial casting for contractures interfering with function 3
• Avoid overhead pulley exercises 3

For Suspected Instability (Age <35):

• Obtain MR arthrography before initiating therapy 3
• Orthopedic referral if labral tear confirmed 3

Red Flags Requiring Urgent Action

• Absent distal pulses → immediate vascular imaging 3
• Neurological deficits → urgent orthopedic/neurosurgical consultation 6
• Fever with shoulder pain → rule out septic arthritis 3
• Unstable or significantly displaced fracture → immediate orthopedic referral 3, 6
• Massive rotator cuff tear in acute trauma → expedited surgical timeline for optimal outcomes 1

Common Diagnostic Pitfalls to Avoid

• Do not assume absence of trauma means absence of fracture—osteoporotic fractures occur with minimal trauma in elderly patients 3
• Do not misinterpret instability pain as impingement or cervical radiculopathy—age-appropriate examination prevents this error 3
• Do not skip the axillary or scapula-Y view—this is the most common cause of missed dislocations 1, 2
• Do not order MRI before radiographs—plain films are mandatory first-line imaging 2
• Do not refer for surgery before 3-6 months of adequate conservative therapy (except for unstable fractures/dislocations)—only 9% ultimately require surgery 3