What Is a Morgagni Hernia? Symptoms, Diagnosis & Repair

A Morgagni hernia is a rare type of diaphragmatic hernia in which abdominal organs push upward through a gap at the front of the diaphragm, just behind the breastbone. The defect is congenital, meaning it forms before birth, but it often goes undetected for decades because roughly a third of people with one never develop symptoms. When symptoms do appear, they tend to be vague enough to get blamed on other conditions. Surgical repair is the standard treatment, and minimally invasive techniques have made it a generally straightforward procedure with low complication rates.

Where the Defect Actually Is

The diaphragm is a dome-shaped muscle that separates your chest from your abdomen. In a Morgagni hernia, the gap sits at the very front of the diaphragm, in the narrow triangle between the xiphoid process (the small cartilage tip at the bottom of your sternum) and the costal attachments where the diaphragm meets the lower ribs. This spot is sometimes called the foramen of Morgagni, named after the Italian anatomist Giovanni Morgagni, who first described the defect in 1769.¹

The hernia overwhelmingly favors the right side. In one series of 21 adults, 19 had right-sided hernias and only 2 had left-sided ones.² A separate study of 17 patients found a similar pattern, with 14 right-sided and 3 left-sided.¹ The left side is somewhat protected by the heart and pericardium sitting above it. Bilateral hernias, where both sides are involved, do occur but are quite unusual.

The contents that herniate through the gap vary. Most commonly it is omental fat, the apron-like tissue that drapes over the intestines. But the transverse colon, small intestine, stomach, and even a lobe of the liver can migrate into the chest cavity.³ How much slides through depends on the size of the defect and how long it has been left alone.

How Common It Is

Morgagni hernias are the rarest major type of congenital diaphragmatic hernia, accounting for only about 2 to 5 percent of all diaphragmatic hernias in adults.¹ The more familiar Bochdalek hernia, which occurs at the back and side of the diaphragm, is far more common.⁴ The estimated congenital incidence of a Morgagni hernia is somewhere around one in every 2,000 to 5,000 births, though many of those cases are never identified at birth.¹

In adults, the average age at diagnosis tends to be in the early sixties, which says less about when the hernia develops and more about how long it takes to be found. One study of 21 adults reported a mean age of about 64 years, while another series of 17 patients found an average age of about 62.²¹ Adults in their twenties and thirties occasionally show up in case reports too. The defect has been present since birth; the question is just when something finally draws attention to it.

Symptoms and Why So Many Cases Slip Through

About 30 to 35 percent of people with a Morgagni hernia have no symptoms at all.⁵ Their hernia gets discovered incidentally, usually when a chest X-ray is done for an unrelated reason and a radiologist notices something odd in the right cardiophrenic angle. When symptoms are present, they are frustratingly nonspecific. The most common complaints include:

Respiratory symptoms: shortness of breath, chronic cough, and recurrent chest infections, caused by abdominal contents compressing lung tissue
Chest or upper abdominal pain: often vague and intermittent, easily mistaken for cardiac or gastrointestinal problems
Gastrointestinal complaints: nausea, vomiting, and changes in bowel habits, particularly when colon or stomach tissue is involved

A systematic review of adult cases confirmed that pulmonary symptoms, abdominal pain, and nausea or vomiting were the most frequently reported complaints.⁶ Because these symptoms overlap with dozens of more common conditions, misdiagnosis is a real problem. One documented case involved a patient with a year of chronic cough and difficulty breathing who was repeatedly treated for recurrent pneumonia before someone finally recognized the real culprit was a Morgagni hernia.⁷

The picture looks a bit different in children. In a pediatric series, 80 percent of the children presented with recurrent chest infections, most of which had been ongoing since early infancy.⁸ About half the children in another pediatric study were symptomatic at diagnosis, meaning the other half were caught incidentally or during workup for associated conditions.⁹

How It Gets Diagnosed

The initial clue is almost always a plain chest X-ray. The classic finding is an unusual density or shadow in the right cardiophrenic angle, the lower-right corner of the chest image where the heart meets the diaphragm. Sometimes gas-filled loops of bowel are visible sitting inside the chest cavity, which makes the diagnosis much more obvious.¹⁰ But a chest X-ray alone is not always enough, especially when the hernia contains only omental fat rather than air-filled bowel. On imaging it can look like a pericardial fat pad, a pericardial cyst, a lung mass, or even a pleural effusion.

CT scanning is the gold standard for confirming the diagnosis. It provides near-perfect sensitivity and shows exactly what organs or tissues have herniated, how large the defect is, and whether there are complications like incarceration.¹¹ The detail a CT provides is also critical for surgical planning, because the surgeon needs to know what is in the hernia sac before operating.¹² Contrast-enhanced CT is generally the recommended study when a Morgagni hernia is suspected.¹³

Why Repair Is Recommended Even Without Symptoms

You might reasonably wonder why surgery is warranted for something that often causes no trouble. The answer comes down to the risk of strangulation. If a loop of bowel or another organ becomes trapped in the hernia and its blood supply gets pinched off, the tissue can die. This is a surgical emergency that carries real danger, and it can happen unpredictably in a hernia that has been silent for years. Surgical repair is therefore recommended for all diagnosed Morgagni hernias, symptomatic or not, because the risk of a future emergency outweighs the risk of an elective repair.¹⁴ One case report described a patient who presented with a bilateral incarcerated Morgagni hernia causing bowel obstruction, exactly the kind of emergency that elective repair aims to prevent.⁵

Surgical Approaches and Techniques

Historically, Morgagni hernias were fixed through open surgery, either through the abdomen (laparotomy) or through the chest (thoracotomy). Both approaches work, but they involve larger incisions and longer recoveries. Laparoscopic repair has become the preferred method for most patients. It offers the advantages of smaller incisions, less postoperative pain, and shorter hospital stays, while providing the surgeon with excellent visualization of the defect.¹⁵

The basic procedure involves pushing the herniated contents back into the abdomen and then closing the diaphragmatic defect. A few technical decisions vary from case to case:

Mesh or no mesh: Some surgeons close the defect with sutures alone, while others reinforce it with a synthetic or composite mesh. The addition of mesh is thought to reduce recurrence, particularly in patients who are overweight, since excess body weight puts extra pressure on the repair.¹⁶
Sac excision or not: Surgeons used to debate whether the hernia sac itself needed to be removed. Current evidence suggests that leaving the sac in place does not worsen outcomes. A systematic review concluded that sac excision does not appear necessary for good results.¹⁷ Leaving the sac undisturbed also avoids the risk of puncturing the pleural space or injuring nearby nerves.¹⁸
Abdominal versus thoracic approach: Most surgeons approach from below (transabdominal), which allows inspection of both sides of the diaphragm and easier reduction of bowel. A thoracic approach, going through the chest, can be useful in specific situations such as obese patients or when the hernia sac contains only omental fat and is densely adhered to chest structures.¹⁹

Robotic-assisted surgery has also entered the picture. The robotic platform gives the surgeon more precise instrument control in the tight spaces near the sternum and pericardium, and a transthoracic robotic approach may reduce the risk of inadvertently injuring abdominal organs during the dissection.²⁰ These techniques are still evolving and are available mainly at larger surgical centers.

Recovery and Outcomes

For an elective laparoscopic repair, the results are generally excellent. In one laparoscopic series, the average hospital stay was under five days, with no deaths, no major complications, and no recurrences during a follow-up period of more than three years.²¹ Another series that left the hernia sac in place reported no recurrences over a median follow-up of 38 months, with only one minor complication: a fluid collection in the residual sac that resolved with breathing exercises alone.¹⁸

When researchers compared outcomes across surgical approaches in adults, laparoscopy showed the highest rate of complication-free survival at 30 days, though the differences between laparoscopic, open abdominal, and thoracic approaches did not reach statistical significance. The most common late complication across all approaches was incisional or port-site hernia, which affected some patients in each group. No 30-day deaths were reported.²²

In children, a meta-analysis comparing laparoscopic and open repair found essentially equivalent complication and recurrence rates. Complication rates hovered around 9 percent for both approaches, and recurrence rates were low in both groups.²³ For children, the choice of approach often depends on the surgeon’s experience and whether other procedures need to be performed at the same time.

The Down Syndrome Connection

One of the more striking things about Morgagni hernia in children is how strongly it is associated with Down syndrome. In a national multicenter study of 53 pediatric cases, about 28 percent of the children had Down syndrome, and about 72 percent had some type of associated anomaly. Congenital heart disease was present in roughly 40 percent of the group, and intestinal malrotation in 15 percent.²⁴ Another report estimated that of every five liveborn infants diagnosed with a Morgagni hernia, three had trisomy 21. The suspected reason involves a disruption during embryonic development: the extra chromosome in Down syndrome appears to increase cellular adhesiveness in a way that interferes with the normal migration of muscle cells that would otherwise close the diaphragmatic gap.²⁵

This matters practically because children with Down syndrome are already undergoing cardiac evaluations and chest imaging at higher-than-normal rates. Knowing the association means that a shadow on a routine chest X-ray in a child with Down syndrome should raise the suspicion of a Morgagni hernia, not just be dismissed as an artifact.²⁶ When both a Morgagni hernia and a cardiac defect are present, surgeons sometimes repair both through a single trans-sternal incision.²⁵

Pediatric Versus Adult Presentation

There are meaningful differences in how Morgagni hernia looks in children compared to adults. In children, the hernia is more commonly found in boys. One pediatric series reported a male-to-female ratio of about 3 to 1, with a median age at diagnosis of just under 15 months.⁹ Diagnosis in infants often happens because recurrent respiratory infections prompt chest imaging, or because the child is being screened for anomalies associated with a known genetic condition. Some pediatric cases are discovered incidentally after unrelated events. In one series, a Morgagni hernia was found after blunt abdominal trauma in one child, after placement of a brain shunt in another, and during workup for liver enlargement in a third.⁸

In adults, the sex ratio flips: women outnumber men in most reported series. The adult with a Morgagni hernia is often overweight and in their fifties or sixties, found incidentally during imaging for something else entirely. Adults are less likely to have the associated cardiac and chromosomal anomalies seen in pediatric patients, but they face other challenges. Obesity raises intra-abdominal pressure and can gradually push more tissue through a defect that has been stable for decades, turning a small, silent hernia into a larger, symptomatic one.

Pregnancy as a Trigger

Pregnancy is one of those situations that can unmask a previously silent Morgagni hernia. The growing uterus increases abdominal pressure dramatically, which can push abdominal contents through the existing diaphragmatic gap. Case reports describe women who had been through previous abdominal surgeries and even prior pregnancies without any sign of trouble, only to have the hernia declare itself later.²⁷ Symptoms during pregnancy, such as worsening breathlessness or upper abdominal discomfort, can be easily attributed to the pregnancy itself, which makes a missed diagnosis even more likely. If repair is needed, surgeons generally try to wait until after delivery when it is safe to do so, but emergency situations require immediate intervention regardless of gestational age.

Weight gain, chronic coughing, and heavy lifting can all raise intra-abdominal pressure in similar ways, and any of these could be the push that turns a lifelong defect into one that starts causing symptoms. This is part of why the average adult patient is diagnosed in middle age or later: the defect has been there since before birth, but it took decades of cumulative mechanical stress before anything squeezed through it in a noticeable way.

1
PubMed Central. Clinical Presentations and Surgical Features of Morgagni Hernia in Adults: A Retrospective Study
2
PubMed Central. Morgagni’s Hernia: Analysis of 21 Patients with Our Clinical Experience in Diagnosis and Treatment
3
PubMed Central. Giant Morgagni hernia with transthoracic herniation of the left liver lobe and transverse colon: a case report
4
PubMed Central. Morgagni hernia: an uncommon pathology in adults
5
PubMed Central. Bilateral incarcerated Morgagni hernia with bowel obstruction: A case report
6
PubMed. Management of Morgagni’s Hernia in the Adult Population: A Systematic Review of the Literature
7
PubMed Central. A rare adult morgagni hernia mimicking lobar pneumonia
8
PubMed. Congenital hernia of Morgagni in infants and children
9
PubMed. Pediatric Morgagni diaphragmatic hernia: a descriptive study
10
Annals of Thoracic Surgery. Foramen of Morgagni hernia: changes in diagnosis and treatment
11
PubMed Central. Symptomatic bilateral Morgagni diaphragmatic hernias in an elderly patient
12
PubMed. Morgagni hernia: diagnosis with multidetector computed tomography and treatment
13
International Journal of Surgery Case Reports. Morgagni hernia in adult: A case report
14
PubMed Central. Laparoscopic repair of a Morgagni hernia with extra-abdominal transfascial sutures
15
PubMed Central. The laparoscopic approach for repair of Morgagni hernias
16
PubMed. Technical description of laparoscopic Morgagni hernia repair with primary closure and onlay composite mesh placement
17
PubMed Central. The surgical treatment of Morgagni hernias in adults: a systematic review for the standardization of laparoscopic surgical repair
18
PubMed Central. Laparoscopic and single incision laparoscopic repair of Morgagni hernia in adults
19
PubMed Central. Morgagni hernia repair in adult obese patient by hybrid robotic thoracic surgery
20
CTSNet. Robotic-Assisted Repair of a Morgagni Diaphragmatic Hernia Utilizing a Thoracic Approach
21
PubMed Central. Laparoscopic approach in the treatment of Morgagni hernia
22
The Annals of Thoracic Surgery. Presentation and Surgical Outcomes of Morgagni Hernia Repair in Adults
23
PubMed. Open Versus Laparoscopic Approach for Morgagni’s Hernia in Infants and Children: A Systematic Review and Meta-Analysis
24
Journal of Pediatric Surgery. Congenital Morgagni’s hernia: A national multicenter study
25
PubMed Central. Concomitant trans-sternal repair of Morgagni hernia and ventricular septal defect in a patient with Down syndrome: A case report
26
The Annals of Thoracic Surgery. Tetralogy of Fallot With Concomitant Morgagni Hernia in Down Syndrome: The Value of Routine Chest Roentgenogram
27
PubMed Central. A rare case of morgagni diaphragmatic hernia presenting in pregnancy