A Broken Breastbone After an Injury
seatbelt, airbag, a fall, or chest compressions

A fracture of the sternum after a road traffic collision is painful, frightening, and in the great majority of people heals without an operation. Two things reassure more than anything else. First, a broken breastbone by itself does not mean the heart has been injured — a normal ECG together with a normal troponin blood test effectively excludes that, and the fracture alone is not a reason for cardiac monitoring. Second, most of these fractures unite over six to twelve weeks with pain relief and time. The situations that need a thoracic surgical opinion are pain that has not settled by three months, a fracture that has not knitted, and a fracture that happened after very little force. Dr Lawrence Okiror, Consultant Thoracic and Robotic Surgeon (GMC 6150382), assesses sternal injuries at London Bridge Hospital and The Lister Hospital Chelsea within 2–3 days. Self-referrals welcome.

Last reviewed: September 2026 · Dr Lawrence Okiror FRCS(CTh) FRCSEd(CTh) · GMC 6150382

The Fracture Alone Is Not a Heart Injury

A normal ECG and a normal troponin together exclude significant blunt cardiac injury. A sternal fracture on its own does not predict it and is not by itself a reason for monitoring.

Most Heal Without Surgery

Six to twelve weeks to unite, with the worst pain in the first fortnight. Surgery is for displaced unstable fractures and for non-union, not for a fracture as such.

Three Months Is the Marker

Pain that is no better at all at three months, with a sense of movement or a click, is the point to have the fracture reviewed rather than give it more time.

  1. A seatbelt or airbag injury to the breastbone means the restraint worked.Both concentrate the force of a sudden stop onto the strongest part of the front of the chest, which is exactly their purpose. Sternal fractures are seen after collisions that left the car looking almost undamaged.
  2. A normal ECG and troponin settle the question about the heart.Where both are normal, significant blunt cardiac injury is excluded and monitoring is not required. The fracture itself is not a predictor and should not by itself drive that decision [1].
  3. A normal chest X-ray does not exclude a sternal fracture.The sternum lies directly in front of the spine and heart, so a standard front-facing film frequently misses it. A lateral view or a CT scan is what shows the fracture.
  4. Pain relief exists so that you can breathe deeply and cough.Shallow breathing and suppressed coughing after a chest injury are what lead to chest infections. Adequate analgesia is a treatment, not a comfort measure.
  5. A fracture that has not knitted by three months can be fixed.Persistent pain with a sense of movement or a click is a symptomatic non-union. A CT confirms it and plate fixation is an effective operation. It is not something to live with unexamined.

Seatbelt, airbag, and why the car looks fine

The seatbelt crosses the front of the chest diagonally and takes the whole force of a sudden deceleration through that strap. An airbag deploys explosively straight into the front of the chest. Both are designed to load the sternum and the chest wall because those structures can take force that the head and neck cannot. A sternal fracture from a restraint is not a sign that the restraint failed. It is a sign that it worked. Worth stating plainly, because people often feel that something must have gone wrong.

It also explains why these injuries so often follow collisions that did comparatively little visible damage. A modest impact is enough when the force is concentrated onto one bone through a narrow strap. People are frequently told that their accident was too minor to have broken anything, and that is simply not how the mechanics work.

Other mechanisms produce the same fracture. A fall onto the front of the chest, particularly in older people. A direct blow in sport. And cardiopulmonary resuscitation — sternal and rib fractures are common after effective chest compressions and are an accepted consequence of compressions deep enough to work.

One group deserves separate mention: a sternum that breaks after very little force at all. That raises the question of whether the bone was weakened beforehand, most often by osteoporosis, which is treatable and worth diagnosing. It is covered further below.

Is my heart damaged?

The breastbone sits directly in front of the heart, so the fear is entirely reasonable. The answer is that this question is settled by two simple tests rather than by the fracture.

A normal ECG and a normal troponin exclude it Taken together, a normal electrical tracing of the heart and a normal troponin blood test effectively rule out significant blunt cardiac injury. This is the standard approach in trauma practice [1].
The fracture itself is not a predictor A sternal fracture on its own does not predict blunt cardiac injury, and its presence should not on its own trigger cardiac monitoring where the ECG and troponin are normal [1].
Echo, CT and MRI have narrower roles An echocardiogram is for those with low blood pressure or an abnormal rhythm rather than for everyone. Cardiac CT or MRI is used where a bruised heart muscle needs distinguishing from a heart attack [1].

Two further points about the immediate assessment, which belongs in an emergency department at the time rather than in a clinic weeks later. A sternal fracture can be accompanied by other injuries — most importantly to the thoracic spine — and those are looked for at the time. The often-quoted figures for associated spinal injury come from major trauma populations and do not describe the person who has broken a sternum in a low-speed collision, so they are worth treating with caution if you meet them online.

If the injury has just happened and you have not been assessed, the emergency department is the right place, not an outpatient appointment. New or worsening breathlessness, chest pain that is different in character from the injury pain, fainting, or an irregular heartbeat all warrant urgent attention.

Broken or bruised, and why the X-ray was normal

By symptoms alone the two are not reliably distinguishable. Both give pain directly over the breastbone, worse on coughing, sneezing, laughing, taking a deep breath, rolling over in bed and getting up from lying flat. Both can produce a band of bruising across the line of the seatbelt, and that bruising is not itself evidence of a fracture.

A normal chest X-ray does not exclude a sternal fracture. The sternum lies directly in front of the spine and the heart, and on a standard front-facing film they are superimposed, so the fracture line is frequently invisible. A lateral view taken specifically to look at the sternum, or a CT scan, is what demonstrates it. People are often told their X-ray was clear and then spend weeks assuming their continuing pain has no explanation.

In practical terms, knowing the answer does not always change the early treatment, which is why imaging is not always repeated at the time. It matters more later: if pain persists, establishing whether there is a fracture and whether it has united is exactly what a CT scan is for. What each test shows is set out on the chest imaging page.

What the first three months should feel like

The bone generally unites over six to twelve weeks. The worst of the pain is in the first two to three weeks, after which there is steady improvement. Deep breaths, coughing, sneezing and getting out of bed remain uncomfortable longest, and progress is not a straight line — a worse day in week five is normal and does not mean something has gone wrong. By around three months most people are comfortable in ordinary activity, with some residual ache on heavy lifting or pushing through the arms.

Take the pain relief properly. The reason is not comfort. Chest wall pain makes people breathe shallowly and suppress coughs, and that is what causes chest infections after a chest injury. Regular simple analgesia taken on a schedule works considerably better than waiting until the pain is bad. Holding a folded towel or cushion firmly against the front of the chest when you cough helps a great deal and costs nothing.

Avoid heavy lifting and anything that pushes hard through the arms while it heals. Sleeping propped up is more comfortable for most people in the first weeks. If breathlessness worsens, or you develop a fever or a productive cough, that needs medical attention rather than being attributed to the fracture.

A fracture that has not knitted by three months

Most sternal fractures unite. A minority do not, and the result is a non-union: the two fragments remain separate, held only by scar tissue, and they move against each other. The description is consistent — a persistent ache over the fracture, a sense of movement, and often a click or a grinding sensation when pushing up out of a chair, lifting, or turning over in bed.

A CT scan confirms whether the bone has knitted, and it is the investigation that turns a vague complaint of ongoing pain into a specific diagnosis. Where a symptomatic non-union is confirmed, the sternum can be fixed with plates, which stabilises the fragments and reliably relieves the mechanical pain and the clicking.

Fixation is also considered early, rather than at three months, in a badly displaced fracture with an unstable segment that moves visibly on breathing. That is uncommon and is usually identified at the time of the injury.

The point worth taking from this section is that persistent pain months after a sternal fracture is not something to simply endure. It has a name, it is demonstrable on a scan, and where it is confirmed it is treatable. People are frequently told there is nothing to be done because the injury is old, and that is not right. The same principle applies to rib fractures that have not settled.

When the injury seems too small for the fracture

A sternum that breaks after a stumble, a minor bump, or in one case a heavy cough, raises a different question from one broken in a collision. The force does not explain the fracture, so the bone itself becomes the question.

The commonest explanation is osteoporosis, and the sternum is one of the sites where fragility fractures occur. Identifying it matters well beyond the chest, because it is treatable and because the next fragility fracture may be a hip. A fracture of this kind is a reason to have bone health assessed rather than simply to wait for the pain to settle.

Less commonly, a bone that is already abnormal fractures through the abnormal area, and the fracture is how the underlying problem first announces itself. That is uncommon, and it is one of the reasons a fracture after trivial trauma is reviewed differently rather than assumed to be bad luck. In someone previously treated for cancer, particularly breast cancer, a new sternal fracture or bony pain is assessed more urgently — that situation is covered on the breast cancer spread to the chest page.

Who to see, and when

Immediately after the injury, the emergency department. The cardiac assessment, the search for other injuries, and adequate pain relief all belong there and cannot be replaced by an outpatient appointment.

Afterwards, a thoracic surgeon is the specialty that owns the chest wall. That is worth naming because people with continuing pain months after a sternal fracture are frequently sent between general practice, orthopaedics and pain services without anyone taking responsibility for the front of the chest. If your pain has not improved at all by three months, if you can feel movement or a click at the fracture, or if the bone broke after very little force, that is the point to be assessed.

Dr Okiror assesses sternal and chest wall injuries at London Bridge Hospital and The Lister Hospital Chelsea, with outpatient consultations also available at the HCA clinics in Canary Wharf and the City of London. Private appointments are typically available within 2–3 working days. Self-referrals welcome. Bring the records and imaging from the time of the injury. Second opinions are available for patients already under another team’s care.

Questions About
a Broken Breastbone

Questions most commonly asked after a seatbelt or airbag injury to the chest, a fall onto the front of the chest, or chest compressions.

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Or call Jo Mitchelson:
020 7952 2882

Can a seatbelt or an airbag break your breastbone?
Yes, and both are recognised mechanisms. The seatbelt runs diagonally across the front of the chest and concentrates the force of a sudden stop onto the sternum, which is why sternal fractures are seen after collisions that did comparatively little damage to the car. An airbag deploys at speed directly into the front of the chest and can do the same. Neither means the restraint failed — both are doing their job, which is to spread a large force across the strongest part of the chest rather than allow it into the head and neck. A sternal fracture from a restraint is a sign that the restraint worked.
Did I break my sternum or just bruise it?
You cannot reliably tell the difference by how it feels. Both produce pain directly over the breastbone, worse on coughing, sneezing, deep breathing, laughing, rolling over in bed and getting up from lying flat, and both can produce visible bruising across the line of the seatbelt. The distinction is made on imaging — and a standard front-facing chest X-ray frequently misses a sternal fracture because the spine and heart lie directly behind the sternum. A lateral view or a CT scan is what shows it. In practical terms the early treatment is similar either way, which is why it is not always necessary to know.
Do I need an ECG and a blood test after a chest injury?
An ECG and a troponin blood test are the standard way of assessing whether the heart has been bruised after a blunt chest injury. Together they are a reliable pair: where both are normal, significant blunt cardiac injury is effectively excluded and no cardiac monitoring is required. If either is abnormal, or if there is low blood pressure or an irregular heart rhythm, an echocardiogram follows. Cardiac CT or MRI has a role in distinguishing a bruised heart muscle from a heart attack where that question arises. This assessment belongs in the emergency department at the time of the injury, not in an outpatient clinic weeks later.
Does a broken sternum mean my heart is damaged?
Not by itself. This is the single most useful thing to know, because the fear is so common. A sternal fracture on its own is not a predictor of blunt cardiac injury, and its presence should not on its own trigger cardiac monitoring where the ECG and troponin are normal. Cohorts of patients with isolated sternal fractures have found clinically significant cardiac injury to be rare. The fracture tells you a substantial force was applied to the front of the chest; it does not tell you the heart was hurt, and the ECG and troponin answer that question directly.
How long does a broken breastbone take to heal?
The bone generally unites over six to twelve weeks, with the worst of the pain in the first two to three weeks and a steady improvement after that. Deep breaths, coughing and getting out of bed are the movements that hurt longest. Progress is not linear and a bad day in week five does not mean something has gone wrong. By around three months most people are comfortable in ordinary activity, with some residual ache on heavy lifting or pushing through the arms. Pain that is no better at all by three months is the point at which the fracture should be reviewed rather than simply given more time.
Will I need an operation for a broken sternum?
Almost certainly not. The great majority of sternal fractures are managed without surgery: pain relief good enough to allow deep breathing and coughing, and time. Surgery is reserved for a small minority — a badly displaced fracture with an unstable segment that moves on breathing, and an established non-union where the bone has not knitted and there is persistent pain and movement at the fracture. Where fixation is indicated, the fracture is plated. The decision rests on displacement, instability and symptoms, not on the presence of a fracture.
What if it has not healed after three months?
A fracture that has not united by around three months is described as a non-union, and it is the situation in which a thoracic surgical opinion is genuinely useful. The typical description is a persistent ache over the fracture with a sense of movement, a click or a grinding sensation when pushing up out of a chair or lifting. A CT scan confirms whether the bone has knitted. Where a symptomatic non-union is confirmed, plate fixation is an effective operation. The important point is that persistent pain months after the injury is not something to simply live with unexamined.
Should I worry if I broke my sternum in a minor fall or a low-speed accident?
It is worth asking why the bone broke so easily. A sternum that fractures after minimal force raises the question of whether the bone itself was weakened — most commonly by osteoporosis, which is a treatable condition and one worth diagnosing. Less commonly, a fracture through an area of bone already affected by disease can be the first sign of that disease, which is why a fracture after trivial trauma is reviewed differently from one after a high-speed collision. This is a reason to be assessed properly rather than a reason to be alarmed.
Can chest compressions break the breastbone?
Yes. Sternal and rib fractures are common after effective cardiopulmonary resuscitation, and they are an accepted consequence of compressions deep enough to circulate blood rather than a sign that anything was done wrong. People who survive a cardiac arrest frequently have significant chest wall pain afterwards, and it is sometimes overlooked while attention is on the heart. It heals in the same way as any other sternal fracture, and it deserves proper pain relief in the meantime because shallow breathing after a cardiac arrest carries its own risks.
What should I do about the pain in the first few weeks?
The purpose of pain relief here is not comfort alone — it is to let you breathe deeply and cough. Chest wall pain makes people take shallow breaths and suppress coughs, and that is what leads to chest infections. Regular simple analgesia taken on a schedule works better than waiting until the pain is bad. Support the front of the chest with a folded towel or a cushion when you cough. Avoid heavy lifting and pushing through the arms while it heals. If breathlessness is worsening, or you develop fever or a productive cough, seek medical attention rather than assuming it is the fracture.
Do I need a GP referral?
Self-referrals welcome — no GP letter is needed before booking. Private appointments at London Bridge Hospital and The Lister Hospital Chelsea within 2–3 days. Bring any imaging from the time of the injury, including emergency department records, so that the review starts from what was already found. If the injury has just happened and you have not yet had a cardiac assessment, the emergency department rather than an outpatient clinic is the right first step. New consultations from £250. Most major insurers accepted.
  1. Clancy K, Velopulos C, Bilaniuk JW, et al. Screening for blunt cardiac injury: an Eastern Association for the Surgery of Trauma practice management guideline. Journal of Trauma and Acute Care Surgery 2012;73:S301–S306.

Pain months after the accident
is not something to simply put up with.

Self-referrals welcome. Private appointments at London Bridge Hospital and The Lister Hospital Chelsea within 2–3 days. Dr Okiror reviews the imaging from the injury personally and establishes whether the fracture has united. If the injury has just happened, go to an emergency department first.

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Jo Mitchelson, PA  · 020 7952 2882 · pa@lungsurgeon.co.uk

St Thomas’ Hospital #1 UK · Guy’s Hospital #2 UK · London Bridge Hospital #10 UK · Newsweek World’s Best Hospitals 2026

Continue Reading

A Scan Has Found SomethingWhat happens next when a scan or blood test has picked up an abnormality in the chest. Chest Wall LumpA lump away from the midline, mobile or soft — lipoma, sebaceous cyst, schwannoma, lung hernia and rib lesions. Wires in the BreastboneBumps or pain over sternal wires after heart or chest surgery, and when they should be removed. Rib Fracture FixationThe same injury often breaks ribs as well — surgical stabilisation for displaced fractures and pain that has not settled. Unexplained Chest PainWhere pain persists after an injury but no fracture is found — costochondritis, slipped rib and other chest wall causes. Xiphoid Process PainA blow to the lower breastbone can injure the xiphoid, and pain there after an injury has its own diagnosis and treatment. Lump or Prominence on the BreastboneA lump felt over the breastbone with no injury behind it — the joint in the sternum, and mild pectus shapes. Chest ImagingWhy a normal chest X-ray does not exclude a sternal fracture, and what CT and MRI each add. Specialist Second OpinionIndependent review of your imaging, investigations and diagnosis before committing to any treatment plan.
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