Hernias (Groin & Ventral)
- A hernia is just stuff (fat, bowel, sometimes other organs) poking through a weak spot in the abdominal wall that's supposed to hold it in.
- The report writes itself if you answer three questions: where is the hole, what's coming through it, and is the contents in trouble?
- Groin hernias split into inguinal (above the pubic line, the common one) and femoral (below it, sneakier and more likely to strangulate). Ventral hernias are everything down the front midline, including hernias through old surgical scars.
- The scary words are incarcerated (stuck, won't reduce) and strangulated (stuck and losing its blood supply). Strangulation is the surgical emergency you're scanning for.
- Your CT findings for trouble: bowel wall that won't enhance, surrounding fat that's getting dirty and streaky, fluid in the sac, and the dreaded narrow neck choking the loop.
Think of the abdominal wall as a slightly worn pair of jeans holding in a lot of leftover Thanksgiving. Most of the time the seams hold. But there are a few spots that were always a little thin — the groin, the belly button, anywhere a surgeon once cut and stitched — and if you cough, lift, or strain enough, the filling bulges out through one of those weak seams. That bulge is a hernia. Honestly, that's the entire disease. Everything after this is just figuring out which seam and how worried to be.
What you're actually naming
A hernia has three parts worth keeping straight: the defect (the hole), the sac (the little pouch of peritoneum that herniates out), and the contents (whatever rode along — fat, a loop of bowel, occasionally bladder or ovary). When I dictate one, I'm just narrating those three things in order, then adding whether the contents look happy or distressed.
The reason radiologists obsess over the exact hole is that location predicts behavior, and CT is genuinely great at showing the hole because it sees the wall layers in cross-section. Ultrasound earns its keep too, especially in the groin, because you can have the patient bear down (a Valsalva) and literally watch the contents pop out in real time — something a static scan can't do.
Groin hernias: the line that decides everything
Down in the groin, one anatomic landmark does most of the work — the inferior epigastric vessels and the inguinal ligament. Where the hernia sits relative to these sorts it into buckets that actually matter clinically.
| Type | Where it pokes through | Why you care |
|---|---|---|
| Indirect inguinal | Lateral to the inferior epigastric vessels, down the inguinal canal | The common one; can ride down toward the scrotum |
| Direct inguinal | Medial to the inferior epigastric vessels, through a weak floor | Bulges straight forward; less likely to slide into the scrotum |
| Femoral | Below the inguinal ligament, medial to the femoral vein | Narrow neck, more likely to strangulate — punches above its weight |
The practical takeaway: inguinal hernias sit above the pubic line, femoral hernias sit below it. Femoral ones are less common but disproportionately dangerous because the neck is tight, like trying to pull a sweater back through a too-small collar. Once bowel is jammed in there, it doesn't slide back out easily.
A femoral hernia compresses and displaces the femoral vein, so on axial CT look for the herniated sac sitting medial to the vein and squashing it. That little squashed-vein sign is a handy tiebreaker when you're trying to decide inguinal versus femoral.
Ventral hernias: the front-of-the-body family
Walk up the midline and you hit the ventral hernias. Umbilical hernias come through the belly-button defect (the original abdominal weak spot — we were all literally plugged in there once). Epigastric hernias come through the midline above it. And incisional hernias come through an old surgical scar, where the wall healed but never got back to full strength — like a patched bike tube that bulges right at the patch.
A special mention for the spigelian hernia, which sneaks out along the lateral edge of the rectus muscle and can hide underneath an intact outer layer, so the patient may have no obvious bulge to feel. CT is the hero there because it sees the defect even when the surface looks normal.
The whole point: is the contents in trouble?
Here's the part that turns a routine read into a phone call. The danger ladder goes: reducible (slides back in, no big deal) → incarcerated (stuck, won't go back) → strangulated (stuck and the blood supply is being choked off). Strangulation is dead bowel waiting to happen, and it's a surgical emergency.
The findings that should make you pick up the phone: bowel wall that fails to enhance (the loop isn't getting blood), wall thickening, surrounding fat stranding (the tissue looks streaky and dirty instead of clean black), fluid within the hernia sac, and a tight, narrow neck choking the loop. Closed-loop physiology applies here — a hernia neck is just another way to kink a loop at two points.
If a hernia contains bowel and that bowel is obstructed, you're really looking at a wall hernia as the cause of a small bowel obstruction — so always trace the dilated loops back to the bulge and check the transition point sits right at the hernia neck.
Not every fat-filled bulge is an emergency, and not every "hernia" the surgeon worries about contains bowel. A sac of pure mesenteric fat with a fat-density stalk and no bowel inside is usually benign and reducible. Don't over-call strangulation on fat stranding alone — confirm it's actual bowel, with a real wall, that isn't enhancing.
A note on the one that lives upstairs
If you're thinking "wait, isn't there a hernia in the chest?" — yes, but that's the hiatal hernia, where the stomach slides up through the diaphragm. Different hole, different neighborhood, separate page. The hernias here all live in the abdominal wall.
So when you meet a hernia, run the checklist: find the hole, name it by where it sits, see what's inside, and decide whether that inside is healthy or strangling. Get those four answers and you've said everything that matters.