What is the workup and treatment for prepatellar or infrapatellar bursitis?

Workup and Treatment for Prepatellar or Infrapatellar Bursitis

The first-line management for prepatellar or infrapatellar bursitis should include relative rest, NSAIDs, and activity modification for 3-6 months before considering more invasive interventions. 1

Diagnosis and Workup

Clinical Assessment

• Location of pain:
  • Prepatellar bursitis: Pain and swelling anterior to the patella
  • Infrapatellar bursitis: Pain below the patella, either superficial or deep
• Physical examination findings:
  • Visible swelling over the affected bursa
  • Tenderness on palpation
  • Pain with knee flexion/extension
  • Possible warmth and redness (if infected)

Diagnostic Imaging

• Plain radiographs (X-rays) should be the initial imaging if symptoms persist beyond 4-6 weeks to rule out other pathologies 1
• MRI without contrast is indicated if symptoms persist despite conservative management for 6-8 weeks, to evaluate for associated tendon tears or other soft tissue injuries 1

Diagnostic Aspiration

• Consider aspiration for:
  • Suspected septic bursitis (fever, significant erythema, warmth)
  • Significant swelling causing discomfort
  • Diagnostic purposes to differentiate between septic and non-septic bursitis 2
• Fluid should be sent for:
  • Cell count and differential
  • Gram stain
  • Culture and sensitivity

Treatment Algorithm

1. Non-Septic Bursitis

First-Line Treatment (0-6 weeks)

• Relative rest: Reduce activities that cause repetitive loading of the affected area 1
• NSAIDs:
  • Naproxen 500mg twice daily (adjust based on response) 3
  • Topical NSAIDs may be used to reduce gastrointestinal side effects 1
• Cryotherapy: Apply ice through a wet towel for 10-minute periods to reduce pain and swelling 1
• Compression: Use elastic bandage to reduce swelling
• Protection: Consider padding for those who must kneel for work 2

Second-Line Treatment (if no improvement after 2-4 weeks)

• Aspiration of bursal fluid (if significant effusion present)
• Corticosteroid injection may be considered for non-septic bursitis that doesn't respond to initial measures 1, 4
  • Limited to 2-3 injections with 4-6 weeks between injections 1
  • Caution: May inhibit healing and reduce tendon strength 1

Physical Therapy Interventions

• Eccentric strengthening exercises for the quadriceps 1
• Stretching exercises to maintain flexibility 1
• Gradual return to activities as symptoms improve 1

2. Septic Bursitis

• Antibiotics:
  • Oral antibiotics for mild cases
  • Intravenous antibiotics for moderate to severe cases or those with systemic symptoms 5
• Aspiration of purulent fluid
• Immobilization with splinting 5
• Surgical drainage if not responding to conservative measures within 36-48 hours 2

3. Chronic or Recalcitrant Bursitis

• Surgical options if symptoms persist despite 3-6 months of well-managed conservative treatment 1, 4:
  • Endoscopic bursectomy: Associated with shorter hospitalization time and higher patient satisfaction compared to open bursectomy 6
  • Open bursectomy: May be necessary for complex cases

Special Considerations

Occupational Factors

• Patients who kneel frequently at work (e.g., carpet layers, roofers) have higher recurrence rates 2, 5
• Workplace modifications and protective kneepads are essential for prevention 2

Prognosis

• Most patients (approximately 80%) fully recover within 3-6 months with appropriate conservative treatment 1
• Patients with preexisting chronic bursitis or those who kneel at work may have persistent symptoms 5

Follow-up Recommendations

• Review at 2-4 weeks after initiating treatment
• If no improvement, consider second-line interventions
• Consider orthopedic referral if:
  • Pain persists despite 3-6 months of well-managed conservative treatment
  • Significant functional limitations impact quality of life
  • Recurrent episodes despite appropriate preventive measures 1