Prepatellar Bursitis
"Housemaid's Knee"
- Anatomy
- Prepatellar bursa is superficial bursa
- Thin synovial lining
- Located between skin and patella
- Main function is to separate patella from patellar
tendon and skin
- Normally does not communicate with joint
- Contains minimal amount of fluid
- Inflammation of prepatellar bursa results in marked
increase of fluid in bursa
- Incidence of prepatellar bursitis greater in males
than females
- Causes
- Direct trauma (eg, a fall on patella or direct
blow to knee)
- If acute, frequently due to small blood vessel
rupture
- Repetitive minor injuries (eg, repeated kneeling)
- Septic or pyogenic process
- Infection usually from Staphylococcus aureus
from break in skin
- More prevalent in children
- Can be mistaken for pyogenic arthritis
- Crystal deposition (eg, gout, pseudogout)
- Occupation
- Carpet layer
- Wrestlers
- Coal miner
- Roofer
- Plumber
- Homemaker (housemaid's knee)
- Clinical findings
- Knee pain
- Swelling
- Redness
- Difficulty walking
- Relief of pain with rest
- History of repetitive motion
- History of occupation requiring excessive kneeling
- History of a fall on knee or blunt trauma to knee
- Physical findings
- Patella tender to palpation
- Fluctuance over lower pole of patella
- Erythema
- Crepitation
- Decreased ROM
- Imaging Studies
- Plain radiographs
- Soft tissue swelling
- Calcification
- Especially if hemorrhage into bursa
Frontal and lateral radiographs of both knees
demonstrate
multiple, punctate calcifications in the pre- and infrapatellar region
- Computed tomography (CT) scan and magnetic resonance
imaging (MRI)
- Complex fluid collection anterior to knee in
region of prepatellar bursa
- Wall of bursa my be thickened and irregular
- Treatment
- NSAIDs
- Cortisone injection
- Aspiration of bursa
- Surgical removal of bursa
- Kneepad
- Has high recurrence rate
Kelly Allen, MD
eMedicine.com
