The olecranon bursa is synovial membrane located immediately posterior to the olecranon bone of the elbow. The bursa's function is to allow the bony olecranon to glide smoothly across the overlying tissues with flexion and extension of the elbow. Olecranon bursitis refers to inflammation of the bursa. The superficial location and limited vascularity make the bursa susceptible to trauma and infection. The diagnosis of olecranon bursitis is often made by clinical evaluation alone without the aid of objective diagnostic testing. However, diagnostic tests become very important when considering the risk of alternative diagnoses or the presence of infection.
The etiology of olecranon bursitis is usually secondary to trauma, underlying inflammatory conditions or infection. Trauma can lead to bleeding within the bursa and the release of inflammatory mediators that predispose it to recurrence. It can also be associated with inflammatory conditions such as rheumatoid arthritis, psoriatic arthritis, and gout, or chronic medical conditions such as diabetes, alcoholism or HIV. Due to the poor vascularity, infection is thought to be via a transcutaneous route, rather than hematogenous spread. Infection is usually secondary to direct inoculation via mild trauma and therefore most commonly includes the typical skin flora.
Olecranon bursitis is relatively common. There is no mortality associated with this condition. Pain in the posterior elbow causes morbidity, with a limitation of activities. It typically affects men between the ages of 30 and 60 years.
Inflammation may also be due to a systematic inflammatory process, like rheumatoid arthritis, or a crystal deposition disease, like gout and pseudogout. This condition may be a side-effect of sunitinib, which is used to treat renal cell carcinoma.
Whether it be traumatic or the introduction of an infectious pathogen, the inciting event causes a reactive inflammation in the bursa. The inflammatory cascade causes the extravasation of protein and synovial type fluid into the bursa. The result is the marked round swelling associated with this condition.
Olecranon bursitis presents as swelling overlying the olecranon process. As the swelling progresses, it can restrict elbow movement. In the initial states, elbow movement is not restricted, distinguishing this from swelling within the elbow joint. The appearance of the bursitis is characteristically round or "golf ball" shape given the fluid's confinement within the bursa.
If bursitis occurs due to underlying infection, it is usually associated with erythema and tenderness. It can also be associated with systemic features such as fever and malaise. It should be noted that fever is only present in approximately 70% of all septic bursitis; therefore, an infectious etiology may not be reliably ruled-out in an afebrile patient.
The experienced clinician will most often make the diagnosis with a history and physical exam alone. It is very important when making the diagnosis, to consider the risk of septic bursitis. Due to both overlapping and variably present signs and symptoms, the average clinician cannot reliably discern between non-infectious bursitis and a mild infectious bursitis without objective diagnostic testing. As such, one must consider the risks and benefits of the mildly invasive aspiration of the bursa required for definitive testing.
Bursal aspiration and analysis are considered to be the gold standard in diagnosis. This is particularly important when underlying infection is being considered. When evaluating to rule out infection, fluid should be sent for cell count, Gram stain, culture and sensitivity tests, and crystal examination. There has also been some belief that serum/bursal fluid glucose concentration differences are markedly more significant in septic cases. However, this has not been validated. When evaluating for septic bursitis, the clinician must also evaluate for the presence of systemic sepsis via careful inspection of vital signs and consider evaluating serum lab tests as necessary.
The treatment for bursitis depends largely on whether it is infective or noninfective. Acute noninfective bursitis is self-limited. It can be managed conservatively with rest, ice, and the use of NSAIDs. Application of elastic bandage has also been shown to help prevent swelling. Some studies have suggested that corticosteroid injection can result in an early reduction in symptoms of olecranon bursitis, but this treatment carries up to a 10% risk of iatrogenic infection. Up to 25% of patients treated with aspiration will have persistent or recurrent swelling at eight weeks, and up to 10% will continue to have persistent symptoms at 6 months. In those with repeated episodes, bursectomy can be considered. The presence of an underlying bone spur is indicative of risk for repetitive recurrence. Patients with a known spur and more than one recurrence should, therefore, be considered for surgical excision of the offending spur. Persistently recurring bursitis without a spur present may benefit from surgical excision of the bursa.
Infective bursitis requires treatment with antibiotics, particularly with antimicrobials targeted against streptococcal and staphylococcal organisms. Aspiration and drainage are highly recommended including disruption of any present loculations. Oral antibiotics are sufficient with no benefit of any dose of intravenous (IV) antibiotics noted. Treatment with oral antibiotics for 7 days is sufficient as there is no evidence of decreased recurrence with longer courses of treatment. Bursectomy is considered for those with recurrent infections or failure to clinically progress despite other treatments. Evidence of systemic infection should include further evaluation of severe sepsis or septic shock with the appropriate up-to-date treatment for either.
The differential diagnosis when considering olecranon bursitis should also include other causes of discomfort or swelling. Among other diagnoses, one might consider cutaneous abscess, hematoma, olecranon fracture, other elbow fracture, cellulitis, tendon rupture, septic arthritis, gouty arthritis, neoplasm, or ligament rupture.
Absent any significant medical co-morbidities, particularly those carrying immunosuppression, olecranon bursitis is relatively benign. The progression to systemic infection from infectious bursitis in the average healthy patient is a very low risk. In fact, there may be a greater chance of spontaneous remission with no treatment in the young healthy patient compared to the risk of progression to systemic disease. However, more objective research is required to substantiate this claim, and conservative treatment with observation typically carries a higher risk of deformity and other complications.
Although the most common cause of olecranon bursitis is blunt injury, symptom onset can be delayed by more than a week and often the patient does not remember the inciting injury at all. In addition, the relatively low risk of infectious etiology plus spontaneous remission allows the common practice to include the complete absence of testing or aspiration during the initial evaluation. Although such conservative evaluation remains relatively safe, it exposes the clinician and patient to possible missed infection. It is highly recommended that any patients with significant comorbidities undergo routine aspiration with fluid analysis as part of their evaluation.
Absent the presence of severe sepsis, or septic shock, patients with olecranon bursitis, are best managed on an outpatient basis. Referral to an appropriate orthopedic surgeon is appropriate when surgical excision of the bursa or underlying bone spur is being considered. Consideration of possible neoplasm should likewise be referred to an appropriate surgeon or oncologist. Otherwise, simple olecranon bursitis is managed by the primary care clinician or another general practitioner.