A “hyena hernia” is a common misspelling of hiatal hernia, a condition where the upper part of your stomach bulges through an opening in your diaphragm and into your chest cavity. It’s one of the most frequently searched medical terms with a phonetic spelling swap, and the condition itself is extremely common. More than 1 in 4 adults has a sliding hiatal hernia by age 40, and prevalence climbs steadily with age, reaching roughly 17% of people in their 80s.
How a Hiatal Hernia Forms
Your diaphragm is the dome-shaped muscle that separates your chest from your abdomen. It has a small opening called the hiatus, which your esophagus (the swallowing tube) passes through on its way to your stomach. In a hiatal hernia, part of the stomach pushes up through that opening and sits in the chest where it doesn’t belong.
The exact cause isn’t always clear. In many cases, the muscles around the hiatus weaken over time, which is why the condition becomes more common as you age. Factors that increase pressure inside the abdomen can contribute: persistent heavy coughing, obesity, pregnancy, frequent straining during bowel movements, or repeated heavy lifting. Some people are born with a larger-than-usual hiatus, which makes them more prone to developing one later in life.
Sliding vs. Paraesophageal Types
There are two main types, and they behave quite differently.
A sliding hiatal hernia is by far the more common type. The junction where the esophagus meets the stomach, along with the top of the stomach itself, slides upward into the chest. It often moves back and forth, slipping up when you strain or lie down and dropping back into place at other times. Most sliding hiatal hernias are small and cause no symptoms at all. Many people only discover they have one when a doctor is investigating something else entirely.
A paraesophageal hernia is less common but more concerning. In this type, the junction between the esophagus and stomach stays in its normal position, but a portion of the stomach squeezes up alongside the esophagus through the hiatus. This creates a pocket of stomach tissue sitting next to the esophagus in the chest. Because the stomach can become trapped or twisted in that position, paraesophageal hernias carry a higher risk of complications, including loss of blood supply to the trapped portion of the stomach.
Common Symptoms
Small hiatal hernias frequently produce no symptoms. When they do cause problems, the symptoms are almost always related to stomach acid flowing backward into the esophagus, a condition called acid reflux or GERD. You might experience:
- Heartburn, especially after meals or when lying down
- Regurgitation of food or sour liquid into your throat
- Difficulty swallowing or a sensation of food getting stuck
- Chest pain that can sometimes mimic heart-related pain
- Feeling full quickly after eating only a small amount
- Shortness of breath, particularly with larger hernias that press on the lungs
Symptoms tend to be worse after large meals, when bending over, or when lying flat. Many people notice their worst episodes at night.
How It’s Diagnosed
A hiatal hernia is often found incidentally during tests for heartburn or chest pain. Three main procedures can identify one. A barium swallow involves drinking a chalky liquid that coats the lining of your digestive tract, making it visible on X-ray so the hernia shows up clearly. An upper endoscopy uses a thin, flexible tube with a camera threaded down your throat to directly view the esophagus and stomach. An esophageal manometry test measures the strength and coordination of muscle contractions in your esophagus when you swallow, which helps evaluate how well the area around the hiatus is functioning.
Dietary and Lifestyle Changes That Help
For most people with a symptomatic hiatal hernia, managing acid reflux through daily habits makes a significant difference. The goal is to reduce the amount of acid that splashes upward and to minimize pressure on the stomach.
Eating smaller, more frequent meals instead of two or three large ones reduces the volume of food pressing against the hiatus at any given time. Eat slowly, chew thoroughly, and sit upright at a table rather than eating on the couch. Take drinks after meals rather than during them to avoid overfilling the stomach. Avoid eating or drinking within a few hours of bedtime.
Certain foods are more likely to trigger reflux symptoms. Fried and fatty foods, spicy dishes, garlic, onions, peppers, strong coffee and tea, alcohol, pickles, vinegar, and acidic fruits tend to be the worst offenders. Strong or melted cheeses and tough, heavily seasoned meats can also be problematic. You don’t necessarily need to eliminate all of these permanently. Most people benefit from cutting them out initially and then reintroducing them one at a time to identify their personal triggers.
Elevating the head of your bed by six to eight inches (using blocks under the bedposts, not just extra pillows) helps gravity keep acid in your stomach overnight. Losing weight if you carry extra pounds around your midsection reduces the pressure pushing your stomach upward.
When Surgery Becomes an Option
Most hiatal hernias never require surgery. Lifestyle changes and acid-reducing medications manage the condition effectively for the majority of people. Surgery typically enters the conversation when symptoms remain severe despite medication, when a paraesophageal hernia puts the stomach at risk of becoming trapped, or when chronic reflux has started to damage the esophagus.
The standard repair involves pulling the stomach back down into the abdomen and tightening the opening in the diaphragm. Surgeons typically perform a fundoplication at the same time, wrapping the top of the stomach around the lower esophagus to reinforce the valve that prevents acid reflux. This is usually done laparoscopically through small incisions, meaning recovery is faster than with open surgery. Most people spend one to three days in the hospital and return to normal activities within a few weeks.
Whether to reinforce the repair with surgical mesh remains an open question. Current evidence is mixed, and surgical guidelines don’t make a firm recommendation either way. The decision depends on the size of the hernia and the surgeon’s assessment of tissue strength during the procedure.
Some patients with both a hiatal hernia and obesity may be offered a gastric bypass as a combined approach, addressing both the hernia and excess weight in a single operation. This is reserved for specific situations and not a routine recommendation.