Usually Harmless. Occasionally Infected. Four Signs Tell You Which.
A soft, squashy swelling has appeared on the pointy tip of your elbow, somewhere between a golf ball and an egg, and it looks far worse than it feels.
That’s olecranon bursitis: a small fluid-filled sac over the tip of the elbow has filled up.
The reassuring part first. Most of these are not serious, don’t need draining, and settle over a few weeks once you stop doing the thing that caused them.
The part that matters. A meaningful number of them are infected, and an infected one needs antibiotics today, not a wait-and-see.
Infected or not: the four signs
Go through these honestly.
- Is it hot and red? Warmth you can feel by comparing with your other elbow, and redness over and around the swelling, points at infection.
- Does it really hurt? The non-infected version is often surprisingly comfortable, uncomfortable when you lean on it and otherwise ignorable. Genuine, constant, throbbing pain is a warning.
- Is there a break in the skin? A scratch, graze, insect bite, shaved skin or a cut anywhere over the elbow gives bacteria a way in. Most infected bursae have one.
- Are you unwell? Fever, chills, or redness spreading up or down the arm means go now, today.
One more useful check: can you still bend and straighten the elbow fully and fairly comfortably? Bursitis sits outside the joint, so the joint itself usually still moves. An elbow that is swollen and genuinely won’t move is a different problem, and a more urgent one.
Soft lump, elbow still bends, not hot: almost always the bursa. Hot, painful, and a scratch in the skin: assume infection until someone rules it out.
What the bursa is and why it fills
The olecranon is the bony point you lean on. Between that bone and the skin sits a thin, flat sac, the bursa, whose entire job is to let skin glide over bone without shredding.
Skin over the elbow tip is loosely attached and there’s almost nothing between it and the bone. So the bursa takes everything.
It fills for three sorts of reasons.
Repeated pressure and friction, which is the common one. Leaning on desks, drawing boards, car door frames, workbenches. It’s been called student’s elbow, plumber’s elbow and miner’s elbow, which tells you everything about who gets it.
A single hard knock, where the bursa bleeds and swells over hours.
Or an underlying condition: gout, which is a classic cause and tends to be far more painful, and rheumatoid arthritis.
Treatment for the ordinary kind
The treatment is unglamorous and it works, provided you actually do the first item.
- Stop leaning on it. Every single time you rest that elbow on a surface eg table or wall – you refill the sac. This is the whole treatment, and it’s the one people skip because it’s free and boring. Please don’t.
- Pad it. An elbow pad or a folded towel where you habitually rest the arm, for the six weeks or so it takes to settle.
- Compression sleeve. Helps the sac collapse down rather than staying stretched.
- Keep moving the elbow normally. There’s nothing to protect inside the joint.
Draining it with a needle is not the routine answer, and this surprises people who arrive wanting exactly that. Aspiration is used mainly to test the fluid when infection or gout is suspected. Drained for cosmetic reasons alone, it usually refills, and it introduces a small risk of infecting a bursa that wasn’t infected.
If it is infected: antibiotics, aspiration to identify the organism, and close follow-up. Surgery is reserved for the ones that don’t settle or keep coming back.
How long, honestly
Pressure removed and padding worn: most settle over 2 to 6 weeks.
But expect a leftover. A bursa that’s been stretched often leaves a thickened, painless, slightly rubbery lump that can hang around for months and sometimes permanently. That’s scar tissue in the sac wall, not ongoing inflammation, and it doesn’t need treating.
Recurrence is the real issue, and it’s almost always the same cause returning. If it comes back twice, the answer isn’t a different treatment, it’s finding the surface you keep leaning on.
The short version
Soft lump on the tip of the elbow, not hot, not very painful, elbow still bends: pad it, stop leaning on it, give it a few weeks.
Hot, red, painful, feverish, or with any break in the skin: get seen today.
And if it’s the second or third time, the lump isn’t the problem. The habit is.
Written by Nigel Chua, hand occupational therapist in practice since 2005. Tens of thousands of hands, wrists and elbows assessed and treated. My credentials are here. This article explains; it doesn’t examine. A hot, red or painful elbow swelling, with or without fever, needs seeing the same day.