What is olecranon bursitis?

What is Olecranon Bursitis

Olecranon bursitis is inflammation of the bursa—a fluid-filled sac located superficially over the bony prominence at the back of the elbow (olecranon process)—which can occur with or without infection and typically results from repetitive trauma, pressure, systemic inflammatory conditions, or infection. 1

Anatomic Location and Pathophysiology

• The olecranon bursa sits between the skin and the olecranon process of the ulna at the posterior elbow 1
• When inflamed, the bursal cavity accumulates fluid and becomes swollen, creating the characteristic "goose egg" appearance at the elbow tip 1
• The condition develops through multiple mechanisms: direct repetitive trauma (hence nicknames like "student's elbow" or "miner's elbow"), systemic inflammatory diseases, crystal deposition, or bacterial infection 1, 2

Clinical Presentation

The condition manifests differently depending on whether it is septic or non-septic:

Non-Septic (Aseptic) Olecranon Bursitis

• Usually self-limiting with localized swelling over the olecranon 3
• May be idiopathic, secondary to repetitive trauma, or associated with rheumatological conditions 3
• Patients typically lack systemic symptoms 3

Septic Olecranon Bursitis

• Caused most commonly by bacterial skin colonizers such as staphylococci and streptococci 3
• Presents with systemic symptoms including fever, warmth, erythema, and tenderness 3
• Requires drainage as the primary treatment rather than antibiotics alone, particularly when purulent collections and surrounding inflammation are present 4
• Rare pathogens like Cryptococcus neoformans can occur, especially in immunocompromised individuals, though cases in immunocompetent patients have been reported 3

Diagnostic Approach

Initial Imaging

• Radiographs are the recommended initial imaging modality to exclude fractures, dislocations, or bony abnormalities 4, 5, 6
• Ultrasound demonstrates bursal thickening and heterogeneous echogenicity in chronic cases 4
• Ultrasound can measure bursal volume, with preoperative volumes averaging around 11 mL in chronic cases 7

Key Diagnostic Considerations

• Bursal fluid aspiration and culture are essential when infection is suspected 3
• In patients with inflammatory arthritis, evaluation for systemic disease involvement is necessary 4
• The clinical course of unusual infections can be subtle and insidious, requiring early microbiologist or infectious disease consultation 3

Associated Conditions

• Repetitive submaximal stress leads to accelerated bone remodeling and can result in olecranon bone spur formation 6
• Athletes such as javelin throwers and baseball pitchers are predisposed to olecranon process fractures and spur formation from repetitive high-force extension movements 6
• The olecranon fossa is a common location for synovitis that can be detected early with ventral longitudinal ultrasound scans over the humeroradial and humeroulnar joints 8

Common Pitfalls

• Failing to distinguish septic from non-septic bursitis can lead to inappropriate treatment—always consider aspiration and culture when infection cannot be clinically excluded 3
• Unusual pathogens may present with subtle symptoms that delay diagnosis and appropriate antimicrobial therapy 3
• Positive bursal fluid cultures occur in only a minority of cases, so clinical judgment remains paramount 7