Knee
Prepatellar Bursitis
슬개전 점액낭염
Inflammation of the prepatellar bursa causing anterior knee swelling ('housemaid's knee')
- How common
- Occupational — Common
- Typical age
- All ages
What is it?
Repetitive friction or direct trauma causes fluid accumulation in the prepatellar bursa. Must differentiate septic (bacterial) from non-septic bursitis.
Commonly affected: Prepatellar bursa, located superficial to the patella
How it develops
- Repetitive Pressure/FrictionOccupational kneeling irritates the prepatellar bursa (housemaid's knee)
- Bursal Fluid AccumulationInflammatory exudate accumulates in bursal sac — visible anterior swelling
- Inflammatory ResponseSynovial irritation causes warmth, tenderness, and redness
- Possible Septic BursitisSkin abrasion allows bacterial entry — Staph aureus most common pathogen
Symptoms
- Localized Anterior SwellingFluctuant, well-defined swelling directly over patella — 'fluid sac' appearance
- Septic Signs (if infected)Fever, erythema, extreme warmth — requires urgent evaluation and aspiration
- Pain with KneelingKneeling directly on bursa is exquisitely painful
- Warmth and TendernessTenderness on direct palpation; warmth overlying bursa
- Limited FlexionSwelling limits full knee flexion; painful with deep flexion
How it is examined
- Fluctuance TestFluid wave (fluctuance) on palpation confirms bursal fluid collection
- No Intra-articular EffusionNo intra-articular effusion — patella ballottement negative; swelling is periarticular
- Partial ROM RestrictionExtension usually full; deep flexion limited by bursal swelling
Imaging
X-ray rules out fracture or intra-articular pathology. Soft tissue density anterior to patella may be visible.
- Soft tissue swelling anterior to patella
- No intra-articular pathology
- Calcification rare in early cases
Ultrasound (preferred) or MRI shows fluid in prepatellar bursa; distinguishes from deep (intra-articular) pathology.
- T2 hyperintense bursal fluid
- No intra-articular effusion
- Peribursal edema/enhancement in septic bursitis
Non-surgical care
- Knee Pad + Activity ModificationEliminate kneeling; padded kneeling pads to protect bursa; ergonomic changes
- Ice + NSAIDsCold therapy and NSAIDs for non-septic inflammatory bursitis
- Bursal Aspiration ± Steroid InjectionAspiration confirms diagnosis; corticosteroid injection reduces recurrence in non-septic cases
Conservative options are generally tried first. Medications listed here can have side effects — discuss them with your prescriber.
When surgery is considered
Septic bursitis failing antibiotics, chronic recurrent bursitis, or persistent bursal mass
Procedures that may be discussed
- Bursectomy for chronic recurrent cases
- Septic: incision and drainage + antibiotics (anti-Staph coverage)
Outlook
Non-septic resolves with conservative care. Septic bursitis requires prompt antibiotics — good prognosis if treated early.