A lung hernia is where part of the lung pushes out through a gap between two ribs. Most people notice it as a soft bulge that appears when they cough or strain and settles back afterwards. It is uncommon, so it is often missed or explained away for a long time before anyone puts a name to it — and it can be repaired. Dr Lawrence Okiror, Consultant Thoracic and Robotic Surgeon (GMC 6150382), assesses and repairs lung hernias at London Bridge Hospital and The Lister Hospital Chelsea. Appointments within 2–3 days. Self-referrals welcome.
Last reviewed: August 2026 · Dr Lawrence Okiror FRCS(CTh) FRCSEd(CTh) · GMC 6150382
Part of the lung pushing out through a gap between two ribs. It appears when you cough, sneeze or strain, and settles back at rest. Some people find it themselves; others are told about it after a scan done for something else.
Previous chest surgery, previous heart surgery through a small incision, broken ribs, or a violent cough. It can appear years after the operation that led to it, which is why people often do not connect the two.
The repair is done on the chest wall from the outside. The chest itself is not opened. The gap is closed, reinforced with a patch, and the ribs are held so they cannot separate again.
A hernia is anything pushing out through a gap it should not fit through. Here, the gap is between two ribs, and what pushes through it is part of the lung, wrapped in the thin lining that normally holds it inside the chest.
It behaves the way other hernias behave. When the pressure inside the chest rises — a cough, a sneeze, a laugh, lifting something — the lung is pushed out through the gap and you see or feel a bulge. When you relax, it usually goes back in. One patient described it as his lung trying to escape, which is a fair description of what is happening.
It is uncommon. Most doctors go a whole career without seeing one, and that is worth knowing, because it explains something that frustrates a lot of people who end up on this page: the length of time it can take before anyone puts a name to it.
There is nearly always a reason, and finding it usually explains the rest. Four causes account for most lung hernias.
Where an incision between the ribs has not held. It can show up months or years later, long after everything appeared to have healed.
People are often surprised to hear this can follow keyhole surgery rather than a big open operation. A small incision is harder to close as securely as a larger one, and there is less holding it. Over time, and particularly in someone who is heavier or who coughs a great deal, that weak point can give way.
Heart operations are increasingly done through a small incision between the ribs on the side of the chest rather than through the breastbone. That incision sits in the same place a lung hernia forms, and it is a recognised thing to happen afterwards. If you have had heart surgery and have noticed a bulge on that side, this is worth having looked at.
An injury to the chest, or ribs broken by coughing, which happens more often than people expect. Ribs that heal out of line can be left permanently further apart than they should be, and the lung finds its way through the gap. Where the underlying problem is the way ribs have healed, the rib fracture page covers that side of it.
Sometimes it happens with no operation and no injury at all, usually at the moment of a violent cough or a heavy strain. It is more likely in people who carry weight around the middle and in those with a long-standing cough. These are often the most alarming to experience, because there is nothing to explain it and it can come on within seconds.
The bulge is the thing most people describe. It comes out when they cough, sneeze, laugh, strain or lift, and it goes back when they stop. Some can feel it moving under the hand. It is often more uncomfortable than painful, and the discomfort is usually worst at the moment the bulge appears.
Bruising over the area, particularly where it came on suddenly. An ache in the same spot that never quite goes. Breathlessness, though this is less common and often has another explanation alongside. A persistent dry cough. And in some people, nothing at all.
That last group is larger than you might expect. A fair number of lung hernias are found on a scan arranged for something else entirely — often a heart scan for chest pain, where the heart turns out to be the cause of the symptoms and the hernia is mentioned further down the report.
It is also common for this to be found last rather than first. People are investigated for their chest pain, or for fluid on the lung, or for their heart, and only after all that does someone examine the chest wall itself and feel the bulge appear when the patient coughs. If that is roughly how it went for you, that is a very ordinary version of this story.
A CT scan shows this clearly, and if you have already had one you may well have read the report before anyone explained it to you. The wording is fairly consistent. It will describe the space between two ribs as widened or splayed, with lung tissue pushing out into the chest wall, and it will often give the size of the gap in millimetres. It may mention old rib fractures.
Occasionally a scan looks normal because the hernia was not out at the time. If that is suspected, the scan can be repeated while you hold your breath and bear down, which brings it into view. More on what each scan does and does not show is on the chest imaging page.
The examination matters as much as the scan. Feeling the chest wall while you cough, and watching what happens, is often what settles it — and it is the step that gets skipped when nobody has thought of the diagnosis. At the consultation Dr Okiror examines the chest wall and then looks through the images with you, on your own scan rather than on a diagram.
Usually, yes. A lung hernia does not settle down on its own, and the gap does not close by itself. If it is causing symptoms, repairing it is what stops them. If it was found by chance and is causing nothing, it is still normally repaired, unless there is a reason it would not be safe or sensible for that particular person.
The reason for not simply leaving it is what can happen to the lung that keeps coming out. Lung that is repeatedly squeezed by the edges of the gap can be damaged, and once it is, a straightforward repair is no longer possible — the damaged part has to be removed as well. That turns a chest wall operation into lung surgery, and it is entirely avoidable.
Where someone has a more pressing problem — heart disease that needs dealing with first is the commonest example — the hernia waits its turn, and that is the right order. The thing to avoid is it being forgotten about altogether once the more urgent issue has been sorted out.
Less than most people expect, and the reason is worth stating plainly at the start.
The chest is not opened. The incision is made directly over the hernia, and the whole repair is done on the chest wall from the outside. The lung itself is not operated on. People who have had chest surgery before, and are dreading a repeat of it, are usually relieved to hear this is a different kind of operation.
The lung is settled back where it belongs. The gap between the ribs is closed and the repair reinforced with a patch. Stitches are then placed around the ribs themselves, so that the two ribs are held together and cannot drift apart again — that is the part aimed at making the repair last, because ribs separating is the original problem. Finally the muscle and tissue over the top are laid back down to cover it.
How much of this is needed depends on the size of the gap. A small hernia needs less than a large one. The principle does not change.
Both synthetic and biological patches are used, and occasionally a mesh. Which suits a particular repair depends on the size of the gap and the tissue around it, and it is discussed with you rather than decided in advance. Whichever is used stays in place permanently and is well tolerated once healed.
Most people are in hospital for a few days. Because this is chest wall surgery rather than lung surgery, there is no lung to recover from, and most people are up and moving about quickly.
The nerves that run along the underside of each rib are easily irritated by an operation in that area. That can leave an ache, or a burning feeling, along or near the scar. It is common, it is not a sign that anything has gone wrong, and it can take weeks and sometimes several months to settle.
It is usually manageable with simple painkillers, and staying active and walking regularly helps rather than harms. Knowing about it beforehand makes a real difference to how people experience it — a symptom that was expected is much easier to live with than the same symptom arriving unexplained.
Like any hernia repair anywhere in the body, a lung hernia can come back, and that is discussed openly beforehand rather than glossed over. Holding the ribs together is the step aimed specifically at preventing it.
You are seen afterwards to check the wound has healed and that things are settling as they should. General guidance on recovering from chest surgery is on the recovery page.
Bring any scan you already have, and any letters about previous chest or heart surgery if you have had either. If nobody has scanned you yet, that can be arranged.
The consultation is straightforward. Dr Okiror examines the chest wall, looks at the images with you, tells you what is happening and whether it needs repairing, and if it does, explains what that would involve for you specifically. If a bulge on your chest turns out to be something else entirely — which happens, and most chest wall lumps are not hernias at all — you will be told that too, and the chest wall lump page covers the other possibilities.
If you have been told nothing can be done, it is worth a second view. Lung hernias are uncommon enough that many clinicians will never have seen one repaired, and people are sometimes told there is no option when there is. A second opinion costs you an appointment and gives you a straight answer either way.
Questions people ask after finding a bulge on the chest, or after a scan report has mentioned a lung hernia.
Book a Consultation →Or call Jo Mitchelson:
020 7952 2882
Self-referrals welcome. Private appointments at London Bridge Hospital and The Lister Hospital Chelsea within 2–3 days, with outpatient clinics at Canary Wharf and the City of London. Bring any scan you already have. Dr Okiror will examine you, look at the images with you, and tell you plainly what is happening and what can be done about it.
Jo Mitchelson, PA · 020 7952 2882 · pa@lungsurgeon.co.uk
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