Synopsis
Distinguish non-septic olecranon bursal swelling from infection, gout, trauma and septic arthritis, sample selectively and safely, treat the cause, and escalate systemic or deep infection before function is threatened.
- Olecranon bursitis produces a discrete fluctuant swelling directly over the posterior elbow; passive joint movement is often relatively comfortable unless the bursa is tense or the joint is involved.
- Always separate septic from non-septic disease using warmth, erythema, skin breach, drainage, fever, immune risk and pain with passive joint movement.
- First-line investigation for uncomplicated pressure-related swelling is clinical assessment; routine aspiration is unnecessary and can introduce infection.
Key red flags
Fever, rigors, tachycardia, hypotension or confusion with posterior elbow swelling requires urgent sepsis assessment and intravenous treatment when indicated.
Investigation priorities
Distinguish bursal swelling from joint effusion, fracture, tendon rupture, cellulitis and solid mass.
Management branches
Pressure-related posterior swelling is minimally inflamed, skin is intact and infection or fracture is unlikely.
- Identify and remove the direct pressure source and provide a properly fitted elbow pad or workplace adjustment.
- Use ice, comfortable compression and the safest short analgesic option while continuing gentle elbow movement.
Key medicines
Topical diclofenac for confirmed sterile painOn intact elbow skin, spread 2–4 g of diclofenac 1.16% gel per dose, using no more than three or four doses daily for a short course and observing the licensed maximum.
Oral flucloxacillin for selected stable septic bursitisWhen local antimicrobial guidance supports outpatient treatment, use flucloxacillin 500 mg to 1 g orally four times daily on an empty stomach, commonly for 7 days initially, then review early and extend or change according to culture, depth and response.