What are the diagnostic criteria and treatment options for shoulder bursitis?

Diagnosing Shoulder Bursitis

For suspected shoulder bursitis with noncontributory radiographs, both MRI without contrast and ultrasound are equally appropriate first-line imaging modalities (rated 9/9), with the choice depending on local expertise availability. 1

Clinical Diagnosis

Shoulder bursitis is primarily a clinical diagnosis based on:

• Pain localized to the subacromial region that worsens with overhead activities and arm elevation 2
• Point tenderness over the subacromial space on palpation 2
• Painful arc of motion typically between 60-120 degrees of abduction 2
• Absence of significant weakness (which would suggest rotator cuff tear rather than isolated bursitis) 2

Important caveat: Bursitis rarely occurs in isolation and commonly accompanies rotator cuff pathology or impingement syndrome, so you must evaluate for these concurrent conditions. 3

Diagnostic Imaging Algorithm

Step 1: Initial Radiographs

• Always obtain plain radiographs first to exclude bony abnormalities, fractures, calcific tendinitis, and acromial morphology issues 4
• Standard views include anteroposterior (internal and external rotation) and axillary or scapula-Y views 1, 4

Step 2: Advanced Imaging (When Radiographs Are Noncontributory)

Choose between two equally appropriate options: 1

Option A: MRI Without Contrast (Rating 9/9)

• Advantages: Visualizes subacromial bursa inflammation, evaluates concurrent rotator cuff pathology, assesses muscle atrophy and fatty infiltration 1, 4
• Use when: You need comprehensive soft tissue evaluation or suspect multiple pathologies 4

Option B: Ultrasound (Rating 9/9)

• Advantages: Real-time dynamic assessment, can guide therapeutic injection simultaneously, no radiation, lower cost 1
• Critical requirement: Must have experienced operator available 1
• Limitations: Operator-dependent, cannot assess deep structures or bone marrow 1, 4

The 2025 ACR guidelines explicitly note that calcific tendinitis and bursitis are covered under chronic shoulder pain protocols, not acute shoulder pain. 1 This suggests bursitis is typically a chronic or subacute condition requiring the chronic shoulder pain imaging approach.

Diagnostic Confirmation

When infection is suspected (septic bursitis):

• Perform bursal aspiration with ultrasound or fluoroscopic guidance (both rated 9/9) 1
• Send fluid for: Gram stain, culture, cell count with differential, glucose level, and crystal analysis 5
• Septic bursitis requires different management with antibiotics effective against Staphylococcus aureus 5

Treatment Considerations

Once bursitis is confirmed:

• Conservative management first: Ice, activity modification, NSAIDs for acute traumatic or microtraumatic bursitis 6, 5
• Ultrasound-guided corticosteroid injection may be considered for persistent symptoms, though high-quality evidence is limited 2, 5
• Address underlying causes: Chronic microtrauma (occupational kneeling/leaning), impingement mechanics, or inflammatory conditions 6, 5

Critical pitfall: Do not inject corticosteroids if septic bursitis is suspected—always aspirate and analyze fluid first. 5 Additionally, avoid injecting chondrotoxic local anesthetics (lidocaine, high-concentration long-acting agents) into joints. 2