Understanding Incisional Hernias
An incisional hernia is a bulge that develops through a weakness in the abdominal wall at the site of a previous surgical incision. It occurs when internal tissue, such as fat or part of the bowel, pushes through the scar where the deeper layers of the abdominal wall have not fully closed or have weakened over time.
This type of hernia can appear months or even years after the original surgery. It may cause discomfort or increase in size over time, and in some cases, lead to more serious complications if left untreated.
How Do Incisional Hernias Develop?
Any time the abdominal wall is cut during surgery, it creates a permanent weak spot in the muscle layer. Even when the skin heals well, the deeper layers may not close completely or may reopen later.
An incisional hernia develops when pressure inside the abdomen pushes tissue through this weakened area.
This is more likely to happen if the wound didn't heal well after surgery or if there’s ongoing strain on the abdominal wall.
Risk Factors
Several factors can increase the risk of developing an incisional hernia, including conditions that affect wound healing or increase pressure in the abdomen:
- Wound infection following the original operation
- Poor wound healing (e.g. diabetes, steroid use, malnutrition)
- Obesity
- Smoking or nicotine use (impairs tissue repair)
- Chronic cough or constipation
- Lifting heavy objects too soon after surgery
- Multiple abdominal surgeries
- Long midline incisions or emergency surgeries
- Liver disease (particularly with fluid build-up)
Symptoms
- A bulge or lump near or under a surgical scar
- A dull ache, dragging sensation, or discomfort over the area
- Pain that worsens with standing, coughing, or straining
- Swelling or pressure that increases during the day
- Rarely, changes in bowel function or bloating
The bulge may flatten or reduce when lying down and become more prominent during activity.
What Can Go Wrong If Left Untreated?
Incisional hernias tend to grow slowly over time. If not treated, they can:
- Cause bowel obstruction if the intestine becomes kinked or compressed within the hernia
- Become larger and more difficult to repair
- Cause discomfort or limit physical activity
- Lead to incarceration (the hernia becomes stuck and cannot be pushed back in)
- Lead to strangulation (blood supply is cut off to the trapped bowel), which is a medical emergency
- In very large hernias, the overlying skin may become stretched or damaged
Diagnosis
Diagnosis usually begins with a physical examination. Your doctor will ask about your surgical history and examine the area for a bulge, especially when standing or coughing.
- Ultrasound: may be used to confirm the presence of a hernia or assess smaller or early cases
- CT scan: may be recommended for larger, recurrent, or complex hernias, especially when planning further treatment
When to See a Doctor
You should speak to your GP or a surgeon if:
- You notice a new lump near a previous surgical scar
- You have pain, discomfort, or pressure in the area
- The bulge is growing or causing cosmetic concern
- You notice redness, tenderness, or changes in your bowel habits
Urgent assessment is needed if the lump becomes very painful, hard, or associated with nausea and vomiting.
Living with an Incisional Hernia
Not all incisional hernias require immediate surgery. Some wide hernias that are not causing pain or symptoms can be safely observed, especially if they are stable in size. Your doctor may recommend regular monitoring and lifestyle changes to help reduce symptoms and prevent progression.
Many people live comfortably with small, stable hernias for years, especially when symptoms are minimal.
To reduce strain on the abdominal wall and slow progression:
- Maintain a healthy weight
- Stop smoking or using nicotine products, as they impair healing and increase hernia risk
- Avoid heavy lifting and straining
- Treat chronic cough or constipation
- Use a hernia support garment if advised by your doctor
Surgical treatment is the only way to definitively repair an incisional hernia.
