Subcutaneous Prepatellar Bursa

bursa subcutanea praepatellaris

The subcutaneous prepatellar bursa lies between the skin and the anterior patellar surface, allowing the skin to glide over the patella during kneeling. It is an acquired bursa developing from repeated kneeling and is commonly inflamed in occupations requiring prolonged kneeling. It contains viscous fluid and has a thin synovial lining. It is entirely superficial to the quadriceps tendon and the patella.

Region: Knee

Clinical Relevance

Clinical Notes

Prepatellar bursitis (housemaid's knee, carpet-layer's knee) produces a swollen, tender, fluctuant anterior knee swelling directly over the patella, palpably separate from the joint itself (joint line is posterior). Aspiration reveals viscous fluid; blood from direct trauma or purulent fluid from infection. Septic prepatellar bursitis (most commonly Staphylococcus aureus) requires aspiration, culture, antibiotics, and may need surgical drainage if not resolving. Chronic prepatellar bursitis from repetitive kneeling is treated by aspiration, corticosteroid injection, and knee padding to reduce ongoing friction.

Pathology

Common Injuries & Conditions

Septic Prepatellar Bursitis

Direct patellar trauma or haematogenous seeding infects the prepatellar bursa producing erythema, warmth, and a tense fluctuant anterior knee swelling without joint space involvement; aspiration of purulent fluid with Gram stain and culture guides antibiotic therapy, and surgical drainage with thorough bursal debridement is required for bursal wall involvement or failed aspiration.