Hernias are usually diagnosed through a physical exam, often in a single office visit. Your doctor will look for a visible bulge, feel the area while you cough or strain, and ask about your symptoms and medical history. In cases where the exam is inconclusive or the hernia is deep inside the body, imaging like ultrasound or CT scans can confirm the diagnosis.
The process varies depending on the type of hernia. A groin hernia that bulges visibly when you stand up is straightforward to identify. A hiatal hernia in your diaphragm or an internal hernia after weight-loss surgery requires specialized imaging. Here’s what to expect for each step of the diagnostic process.
What Your Doctor Asks First
Before any hands-on exam, your doctor will ask targeted questions to assess your risk and narrow down the type of hernia. Expect questions about whether you’ve noticed a bulge, where exactly the pain is, whether the bulge can be pushed back in, and whether you have nausea or vomiting. They’ll also ask about previous hernia repairs and whether mesh was placed during a prior surgery.
Several questions focus on conditions that increase abdominal pressure. Your doctor will want to know about chronic coughing, smoking, lung conditions like COPD or asthma, difficulty urinating, frequent urination, and digestive problems including constipation. These all create repeated strain on the abdominal wall and raise the likelihood that a hernia has developed. You may also be asked about your activity level, including whether you have difficulty with moderate physical tasks like vacuuming, golf, or dancing, which helps gauge how much the hernia is affecting your daily life.
The Physical Exam
For a suspected groin hernia, the exam is done with you standing while your doctor sits on a stool facing you. This position lets gravity pull the hernia contents downward, making a bulge easier to spot. Your doctor will first observe the groin area in angled light while you relax, then ask you to cough. A bulge or abnormal movement during the cough is a strong initial clue.
Next comes direct palpation. Your doctor places fingers over three key areas of the groin: the femoral region (near the top of the thigh), the external inguinal ring, and the internal ring. You’ll be asked to cough again while they feel for a palpable impulse or bulge at any of those points. In men, the exam also involves gently inverting the scrotal skin so the doctor’s index finger can follow the inguinal canal. A bulge felt against the side of the finger suggests a direct hernia (where tissue pushes through a weak spot in the abdominal wall), while a bulge felt at the fingertip near the internal ring suggests an indirect hernia (where tissue follows the natural canal).
If a mass is found, the doctor will gently press on it to see if the hernia contents can be pushed back into the abdominal cavity. This is called reducing the hernia. One critical exception: if the mass is tender to the touch or you’re experiencing nausea and vomiting, the doctor will not attempt to push it back. Those signs suggest the hernia may be strangulated, meaning blood flow to the trapped tissue is compromised.
When Ultrasound Is Used
If the physical exam doesn’t clearly reveal a hernia but your symptoms suggest one, ultrasound is typically the next step. It’s painless, uses no radiation, and can be done in real time while you bear down or perform a straining maneuver. The sonographer places the probe along the groin in an angled position, identifies key blood vessels as landmarks, and then asks you to strain. This reveals whether fat or bowel is pushing through a gap in the abdominal wall.
Ultrasound is highly accurate for groin hernias. One comparative study found it detected 100% of indirect inguinal hernias and 80% of direct inguinal hernias. The imaging also measures the size of the defect, which correlates well with what surgeons find during repair. In that study, the average defect measured about 22 mm on ultrasound compared to 27 mm at surgery, a close enough match to help with surgical planning.
Ultrasound is also useful for ruling out conditions that mimic a hernia. Swollen lymph nodes, fluid collections along the spermatic cord (hydroceles), enlarged veins in the scrotum (varicoceles), and even testicular tumors can all present as a groin lump. In some cases, shining a light through the scrotum in a dark room (transillumination) helps distinguish a fluid-filled hydrocele from a hernia containing bowel.
When CT Scans Are Needed
CT imaging becomes the preferred tool when the suspected hernia is located deep in the pelvis or chest, where neither a physical exam nor ultrasound can reach effectively. The American College of Radiology rates CT as “usually appropriate” and ultrasound as “usually not appropriate” for several specific hernia types.
Deep pelvic hernias, such as obturator, sciatic, or perineal hernias, are notoriously difficult to diagnose. Symptoms are vague: about 63% of patients present with bowel obstruction, 57% with hard-to-localize abdominal or groin pain, and 37% with thigh pain that radiates to the knee. Only 10% have a palpable lump. These hernias are often discovered incidentally when a CT is ordered to investigate the cause of a bowel obstruction.
Diaphragmatic hernias, where abdominal organs push through the diaphragm into the chest, also require CT for reliable detection. In adults, these are uncommon and frequently found by accident on imaging done for unrelated reasons. CT detects traumatic diaphragmatic hernias with a sensitivity between 56% and 82% and a specificity up to 100%, with the ability to view the area in multiple planes being particularly valuable.
Internal Hernias After Gastric Bypass
Internal hernias deserve special mention because they have no external bulge at all. They occur when bowel loops slip through an opening inside the abdomen, most commonly after weight-loss surgery like gastric bypass. On CT, doctors look for specific patterns: a U-shaped or C-shaped loop of distended, fluid-filled bowel, or a cluster of dilated loops crowded together in an abnormal location. A swirling pattern of the blood vessels supplying the bowel (sometimes called a mesenteric swirl) is one of the most accurate signs. If the trapped bowel has lost its blood supply, the surrounding vessels appear engorged and twisted at the point where the hernia pinches them.
How Hiatal Hernias Are Diagnosed
Hiatal hernias, where part of the stomach slides upward through the diaphragm, are diagnosed differently from abdominal wall hernias. The two main tools are a barium swallow (a type of X-ray) and endoscopy, where a flexible camera is passed down the throat into the esophagus and stomach.
On a barium swallow, a sliding hiatal hernia is identified when the junction between the esophagus and stomach is separated from the diaphragm by more than 2 cm. When that landmark isn’t clearly visible, the presence of stomach folds crossing above the diaphragm serves as the defining feature. In practical terms, small hiatal hernias (under 3 cm) are unreliable to detect on barium swallow unless the radiologist follows a strict measurement protocol.
Endoscopy diagnoses hiatal hernia using similar measurements, identifying separation between the visible boundary of the stomach lining and the impression of the diaphragm. The endoscope has markings spaced 5 cm apart to help with measurement. The doctor can also flip the camera backward (retroflexion) to look at the opening from below. In the most advanced cases, no muscular ridge exists at the stomach entry, the junction stays open permanently, and esophageal tissue is visible from the retroflexed view. A hiatal hernia is always present at that stage. As with barium swallow, small hernias under 3 cm are difficult to reliably identify on endoscopy without a standardized technique.
Sports Hernias Are Not True Hernias
If you’re an athlete with chronic groin pain, you may have heard the term “sports hernia.” Despite the name, most cases involve no actual tissue pushing through a hole in the abdominal wall. The condition, more accurately called athletic pubalgia, refers to tears or strain in the muscles and tendons of the lower abdomen and groin.
Diagnosis relies heavily on a structured physical exam that systematically tests for multiple causes of groin pain. Tenderness where the inner thigh muscles attach to the pelvis, combined with pain when you resist pulling your legs together, points toward an adductor-related problem. Tenderness at the pubic bone itself suggests a pubic-related source. Pain with resisted hip flexion or stretching of the hip flexors implicates a different muscle group. Your doctor may also perform specific hip rotation tests to check for joint problems that mimic a sports hernia.
Most patients with athletic pubalgia have normal imaging results. MRI is the most sensitive option and can reveal tears at the junction of abdominal and thigh muscle tendons, or inflammation at the pubic bone. However, these findings aren’t unique to athletic pubalgia and can appear in people without symptoms. MRI’s primary value is ruling out other causes of chronic groin pain rather than confirming the diagnosis on its own.
Signs That Need Emergency Attention
Most hernias are diagnosed in routine, non-urgent settings. But a hernia that becomes incarcerated (stuck and unable to be pushed back in) can progress to strangulation, where blood supply to the trapped tissue is cut off. Trapped intestine can begin to die in as little as four hours once blood flow is reduced.
The warning signs are a painful bulge in the abdomen or groin that keeps getting worse, nausea and vomiting, and skin color changes around the lump. The skin may turn reddish or darker than usual. If you notice sudden, severe pain along with skin that first becomes paler than normal and then darkens, that pattern signals tissue losing and then being deprived of blood flow. In these situations, diagnosis happens rapidly in the emergency department, often with a CT scan, and leads directly to surgery.