How many layers are cut during hernia surgery?

September 22, 2025 •

3 min read

During an open hernia repair, a surgeon cuts through multiple layers of the abdominal wall, including skin, fat, and muscle fascia, to access the weakened area. Understanding the specific anatomical layers involved in how many layers are cut during hernia surgery can help demystify the procedure and better inform patients about their treatment options.

Quick Summary

The number of layers cut during hernia surgery depends on the technique, with open surgery involving incisions through several distinct abdominal wall layers, while laparoscopic surgery requires a few small incisions, allowing the repair to be done from behind the abdominal wall with minimal cutting of the muscle layers.

Key Points

Open Surgery: Involves a single, larger incision directly over the hernia, cutting through several layers of skin, fat, and muscle fascia to access the site.
Laparoscopic Surgery: Uses several small incisions away from the hernia, with instruments passed through to work from behind the abdominal wall, thus avoiding extensive cutting of the muscle layers.
Abdominal Wall Layers: The layers that can be cut in open surgery include skin, subcutaneous fat, external oblique aponeurosis, and transversalis fascia.
Non-Mesh Repairs: Techniques like the Shouldice repair involve cutting and reconstructing multiple fascial layers with sutures to reinforce the abdominal wall.
Method Dependent: The specific layers cut vary significantly based on whether an open or laparoscopic technique is used, highlighting the importance of the surgical approach.
Skill is Crucial: Regardless of the method, the surgeon's skill in navigating the anatomy is key to minimizing complications and ensuring a successful repair.

Understanding the Abdominal Wall Layers

To grasp what happens during a hernia repair, it helps to first understand the anatomy of the abdominal wall. From the outside in, the abdominal wall is composed of several distinct layers:

Skin: The outermost layer.
Subcutaneous tissue: The fatty layer just beneath the skin, containing Camper's and Scarpa's fascia.
Muscular layers: This includes the aponeuroses of the external oblique, internal oblique, and transversus abdominis muscles.
Transversalis fascia: A deeper layer of connective tissue.
Preperitoneal fat: A fatty layer situated just outside the peritoneum.
Peritoneum: The thin membrane lining the inside of the abdominal cavity.

Open Hernia Repair: Cutting Through the Layers

In an open hernia repair, the surgeon makes a single, longer incision directly over the hernia. This requires cutting through several abdominal wall layers to access and repair the hernia. The initial incision goes through the skin and subcutaneous fat. To reach the inguinal canal, the external oblique aponeurosis is opened. For deeper repairs, the transversalis fascia may also be incised or separated to access the preperitoneal space. The hernia sac, which is a protrusion of the peritoneum, is then identified and managed. The number of layers cut is significant and depends on the specific hernia.

Laparoscopic Hernia Repair: A Minimally Invasive Approach

Laparoscopic surgery uses a different technique with minimal cutting of abdominal wall muscles. Instead of one large incision, several small incisions are made, typically away from the hernia site, to insert surgical instruments and a camera. These small cuts go through the skin and subcutaneous tissue. The abdomen is inflated with gas to create space, allowing the surgeon to work from behind the abdominal wall. This approach reinforces the weakened area with mesh without cutting through the major muscle layers, a key difference that can contribute to faster recovery.

Comparing Open vs. Laparoscopic Repair Layers

The choice between open and laparoscopic surgery considers factors like recovery and the extent of incisions. The table below highlights how each method addresses the abdominal wall layers during an inguinal hernia repair.


Feature	Open Hernia Repair	Laparoscopic Hernia Repair
Incision Size	Single, larger incision (several inches)	Several small incisions (less than an inch)
Layers Incised	Cuts through skin, fat, aponeurosis, and fascia directly over the hernia	Small cuts through skin and fat, then instruments are inserted through ports to work from behind the muscle wall
Muscle Involvement	Incises and separates muscular fascia to access the repair site	Avoids cutting major muscle or fascial layers in the repair area
Approach	Direct, external approach	Internal, extraperitoneal or transabdominal approach
Mesh Placement	Placed over or under the repaired defect	Placed behind the abdominal wall to reinforce the defect

Tissue-Based Repair Options

Some hernia repairs utilize the patient's own tissue for reinforcement, which also involves specific cuts and manipulation of abdominal wall layers.

Shouldice Repair

This non-mesh technique involves a four-layer tissue reconstruction. The procedure includes incising the skin, subcutaneous fat, and external oblique aponeurosis. The floor of the inguinal canal, the transversalis fascia, is cut, and its layers are then overlapped and sutured to create a strong repair without mesh. This method emphasizes meticulous layered suturing. For more details, consult the Shouldice Procedure (Non-Mesh Hernia Repair) information from Columbia University Department of Surgery.

Bassini Repair

The Bassini procedure involves cutting the external oblique aponeurosis and performing a layered repair. The conjoined tendon (formed by the internal oblique and transversus abdominis muscles) is sutured to the inguinal ligament. This technique directly manipulates and sutures muscle and tendon layers to repair the hernia.

The Role of the Surgeon's Skill

The number of layers cut is ultimately a decision made by the surgeon based on the hernia and the patient's anatomy. The surgeon's skill is crucial in both open and laparoscopic procedures. In open repair, precision is needed when cutting through layers to avoid damaging nerves and blood vessels. In laparoscopic surgery, skill is required to maneuver instruments within the abdominal space without directly cutting muscle.

Conclusion

The number of layers cut during hernia surgery depends on the surgical method. Open repair involves incising multiple layers, including skin, fat, and muscle aponeuroses, to reach the hernia. Laparoscopic surgery uses small incisions and repairs the hernia from inside the abdominal wall, largely avoiding extensive muscle layer cuts. Understanding these differences helps in informed decision-making about treatment.

Frequently Asked Questions

During an open inguinal hernia repair, the surgeon typically makes an incision through the skin, subcutaneous fat layers (Camper's and Scarpa's fascia), and the external oblique aponeurosis to access the inguinal canal. In some cases, the transversalis fascia may also be cut or separated.

No, major abdominal muscles are not cut during a standard laparoscopic hernia surgery. The procedure uses small incisions through the skin and fat, and the repair is performed from behind the abdominal wall, leaving the muscle layers largely intact.

A non-mesh repair, like the Shouldice technique, involves a multi-layered tissue reconstruction where specific layers of fascia, including the transversalis fascia, are cut and then overlapped with sutures to reinforce the abdominal wall. The procedure involves meticulously suturing these layers rather than simply placing mesh.

For a standard laparoscopic hernia repair, a surgeon typically makes three small incisions: one for a tiny camera (laparoscope) and two for the surgical instruments. These cuts are usually away from the hernia site itself.

The peritoneum is the membrane lining the abdominal cavity. In open hernia surgery, the hernia sac, which is an outpouching of the peritoneum, is dealt with, but the main peritoneum is usually not cut extensively. In transabdominal laparoscopic surgery (TAPP), the peritoneum is cut to create a flap and gain access to the preperitoneal space where the mesh is placed.

Cutting fewer muscle layers in laparoscopic surgery often leads to less pain and a faster recovery compared to open surgery. This is because there is less trauma to the abdominal wall muscles, which are crucial for core strength and movement.

Yes, the surgical procedure and the layers involved vary depending on the type of hernia (e.g., inguinal, umbilical, incisional) and the surgical approach (open, laparoscopic, robotic) chosen by the surgeon.