Prepatellar Bursitis

Blausen Medical · Wikimedia Commons · CC BY-SA 4.0

The prepatellar bursa sits directly over the kneecap between the skin and the patella. It can become swollen and painful from repetitive kneeling (plumber's knee, carpet layer's knee), a direct blow, gout, or infection. Septic (infected) prepatellar bursitis is a distinct condition requiring urgent treatment.

Visible, fluctuant swelling directly over the kneecap — the swelling is anterior to the joint, not inside it, so range of motion is typically preserved. Aspiration of the bursa (with fluid analysis for cell count, crystals, and culture) distinguishes septic from non-septic bursitis. MRI differentiates bursitis from other anterior knee pathology.

1. Corticosteroid injection

   Injection after aspiration for non-septic, non-crystalline bursitis reduces recurrence.

2. Antibiotics

   IV or oral antibiotics for septic bursitis; surgical drainage if it does not respond.

Septic bursitis not responding to aspiration and antibiotics, or chronic recurrent bursitis after multiple aspirations, may require surgical bursectomy.

External patient-education references and related OSI pages for additional background:

• Britannica — Bursitis
• Britannica — Knee (anatomy)
• AAOS OrthoInfo — patient education library
• OSI glossary — orthopedic terminology in plain language