What is the appropriate management for knee bursitis?

Management of Knee Bursitis

Knee bursitis should be managed based on the underlying etiology: acute traumatic/hemorrhagic bursitis requires conservative treatment with ice, elevation, rest, and analgesics; chronic microtraumatic bursitis needs conservative management with activity modification and addressing the underlying cause; inflammatory bursitis (gout, rheumatoid arthritis) requires treatment of the underlying condition plus intrabursal corticosteroid injections; and septic bursitis demands antibiotics effective against Staphylococcus aureus with hospitalization for acutely ill patients. 1

Initial Diagnostic Approach

Distinguish the type of bursitis first, as management differs fundamentally:

• Assess for infection signs: warmth, erythema, fever, or systemic symptoms suggesting septic bursitis 1
• Identify trauma history: acute injury with hemorrhage versus chronic repetitive microtrauma (e.g., prolonged kneeling on prepatellar bursa) 1
• Evaluate for inflammatory conditions: gout, rheumatoid arthritis, or other systemic inflammatory disorders 1
• Use ultrasonography to distinguish bursitis from cellulitis when clinical presentation is unclear 1

Septic Bursitis Management

If infection is suspected, perform bursal aspiration immediately and examine fluid with Gram stain, crystal analysis, glucose measurement, blood cell count, and culture 1:

• Start antibiotics effective against Staphylococcus aureus as initial empiric therapy (most common pathogen) 1
• Hospitalize acutely ill patients and administer intravenous antibiotics 1
• Consider outpatient oral antibiotics only for patients who are not acutely ill 1
• Reserve surgery for cases not responsive to antibiotics or recurrent septic bursitis 1

Acute Traumatic/Hemorrhagic Bursitis

Treat conservatively as first-line approach 1, 2:

• Apply ice, elevation, and rest to reduce inflammation 1, 3
• Prescribe analgesics for pain control 1
• Consider aspiration to shorten symptom duration, though this is optional 1
• Avoid corticosteroid injection in acute traumatic cases 1

Chronic Microtraumatic Bursitis

Address the underlying repetitive trauma (e.g., occupational kneeling, athletic activities) 1:

• Implement activity modification and relative rest 1, 3
• Apply ice, compression, and elevation as needed 3
• Prescribe NSAIDs for symptomatic relief 4, 3
• Do NOT aspirate microtraumatic bursitis due to risk of iatrogenic septic bursitis 1
• Avoid intrabursal corticosteroid injections as high-quality evidence demonstrating benefit is unavailable 1

Common Pitfall

Many clinicians inappropriately inject corticosteroids into chronic microtraumatic bursitis, but this lacks evidence and increases infection risk 1.

Chronic Inflammatory Bursitis

Treat the underlying inflammatory condition (gout, rheumatoid arthritis) as primary management 1:

• Use intrabursal corticosteroid injections combined with analgesics, which are appropriate in this context 1, 2
• Aspirate fluid if significant effusion is present 2
• Prescribe NSAIDs as adjunctive therapy 4
• Consider immobilization temporarily during acute flares 2

Emerging Biologic Therapies

For refractory cases, particularly pes anserine bursitis, platelet-rich plasma (PRP) and PRP combined with hyaluronic acid show improved pain relief and reduced recurrence compared to corticosteroids (20-40% recurrence rate) 5:

• PRP-based therapies demonstrate promising results in Level I-II studies, though protocols remain heterogeneous 5
• Reserve biologics for cases failing conservative management and corticosteroid injections 5

Surgical Intervention

Consider surgical excision for chronic bursitis refractory to conservative management 2, 4:

• Indications include: recurrent septic bursitis, persistent symptoms despite 3-6 months of appropriate conservative treatment, or significant functional impairment 2, 4
• Surgery is particularly relevant for recalcitrant prepatellar and olecranon bursitis 4

Location-Specific Considerations

Prepatellar and superficial infrapatellar bursae (anterior knee pain) 1, 4:

• Most commonly affected by chronic microtrauma from kneeling 1
• Corticosteroid injection may be used if inflammatory etiology confirmed 4

Pes anserine bursa (medial knee pain) 5:

• Strongest evidence for PRP therapy in refractory cases 5
• Often associated with obesity and knee osteoarthritis 5

Retrocalcaneal bursa (posterior knee/heel) 4:

• Avoid steroid injection as it may adversely affect Achilles tendon biomechanical properties 4