What triggers abdominal adhesions?

October 2, 2025 •

5 min read

According to the Cleveland Clinic, abdominal adhesions are the most common consequence of abdominal surgery, affecting a large majority of patients. This dense, internal scar tissue can cause tissues and organs to stick together, raising crucial questions about what triggers abdominal adhesions.

Quick Summary

Abdominal adhesions are triggered primarily by inflammation or injury within the abdominal cavity, with the most frequent cause being abdominal surgery. Other triggers include infections, chronic inflammatory diseases like endometriosis, radiation therapy, and less commonly, congenital factors.

Key Points

Surgical Trauma: The most common trigger for abdominal adhesions is surgery, especially open procedures that involve larger incisions and greater tissue handling.
Inflammatory Conditions: Non-surgical triggers include infections like appendicitis, peritonitis, and pelvic inflammatory disease, as well as chronic conditions like endometriosis and Crohn's disease.
Impaired Healing Response: Adhesions form due to a complex imbalance between the body's natural processes of fibrin formation and fibrinolysis after injury, leading to persistent scar tissue.
Risk Reduction Strategies: Minimally invasive (laparoscopic) surgery and the use of adhesion barriers during a procedure can help reduce the risk of adhesion formation.
Potential Complications: While many adhesions are asymptomatic, they can cause serious problems such as bowel obstruction, chronic pain, and female infertility when they interfere with organ function.
Ongoing Risk: Adhesions can form and cause problems years after the initial trigger, and can even recur after surgical removal.

Understanding Abdominal Adhesions

Abdominal adhesions are fibrous bands of scar tissue that form within the abdominal and pelvic cavities. Under normal circumstances, the internal tissues and organs are coated with a smooth, slippery surface called the peritoneum, which allows them to move and slide against each other effortlessly. When the peritoneum is injured or inflamed, the body's healing response creates a type of internal scarring. This scar tissue can cause organs and tissues to become stuck together, leading to potential complications. These fibrous bands can be thin and filmy or thick and dense, and while most cause no issues, some can lead to significant pain or serious medical problems over time.

The Primary Catalyst: Abdominal Surgery

Abdominal surgery is by far the most common cause of adhesions, triggering them in a majority of cases. The body’s natural healing response to the trauma of surgery is to form scar tissue, but sometimes this process overreacts, leading to adhesions.

How Surgery Leads to Adhesions

Tissue Incisions and Handling: The cutting and manipulation of internal organs and tissues during an operation inflict a certain amount of trauma. This trauma is a key trigger for the healing process that can result in adhesion formation.
Foreign Materials: The body's immune system can react to foreign materials introduced during surgery. This includes materials like gauze, surgical gloves, and stitches, which can exacerbate the inflammatory response and subsequent scarring.
Tissue Dehydration: During prolonged open surgeries (laparotomy), internal tissues can become dried out from exposure to the air, light, and heat of the surgical environment. This can stimulate the formation of adhesions.
Blood and Blood Clots: Any residual blood or blood clots not fully rinsed from the abdominal cavity can act as a breeding ground for inflammation, creating a foundation for scar tissue to form.

The Impact of Surgical Approach

The surgical approach plays a significant role in adhesion risk. Open surgery (laparotomy), which involves a large incision, carries a much higher risk of adhesion formation than minimally invasive laparoscopic surgery, which uses smaller incisions. However, even laparoscopic procedures can trigger adhesions, particularly if surgery time is long or if higher insufflation pressure is used.

Non-Surgical Triggers of Inflammation and Injury

While surgery is the leading cause, adhesions can also develop from other sources of inflammation or injury within the abdomen.

Inflammatory Conditions

Certain chronic conditions and infections are well-known to cause inflammation that can lead to adhesions:

Appendicitis: An inflamed or ruptured appendix is a common non-surgical trigger for adhesions.
Endometriosis: This condition, where tissue similar to the uterine lining grows outside the uterus, can cause inflammation, bleeding, and scarring that triggers pelvic and abdominal adhesions.
Pelvic Inflammatory Disease (PID): An infection of the female reproductive organs, PID can cause widespread inflammation and scar tissue in the pelvic and abdominal region.
Crohn's Disease and Diverticulitis: These inflammatory bowel diseases involve chronic inflammation that can damage the intestinal lining and lead to adhesions over time.

Other Abdominal Trauma and Treatments

Radiation Therapy: High-energy radiation used to treat cancer can damage internal tissues and cause inflammation, resulting in adhesions.
Peritoneal Dialysis: This treatment for kidney failure can cause inflammation of the peritoneum, leading to adhesion formation over the long term.
Congenital Adhesions: In very rare cases, a person can be born with adhesions, though these are typically asymptomatic and are discovered incidentally.

The Pathophysiology Behind Adhesion Formation

At a molecular level, the formation of adhesions is a complex process resulting from an imbalance in the body’s healing and repair systems. The standard process for healing a peritoneal injury involves fibrin, a clotting protein, which forms a temporary mesh. Normally, the body's fibrinolytic system, driven by enzymes like tissue plasminogen activator (tPA), breaks down this fibrin mesh. When this process is impaired or overwhelmed by excessive fibrin deposition, the fibrin mesh persists.

This persistent fibrin then becomes a scaffold for fibroblasts to migrate and deposit collagen, forming more permanent, fibrous scar tissue. Factors that contribute to this imbalance include: reduced oxygen supply (hypoxia) to the tissues, bacterial contamination, and the release of pro-inflammatory cytokines and growth factors, such as TGF-beta, which further promote fibrosis. This abnormal wound healing is what ultimately creates the bands of tissue that can restrict organ movement and cause complications.

Key Risk Factors for Developing Abdominal Adhesions

Multiple factors can influence an individual's likelihood of forming problematic adhesions. Being aware of these risk factors is important for patients and clinicians alike.


Risk Factor	Description	Impact on Adhesion Formation
Previous Surgery	History of any abdominal or pelvic surgery.	The risk increases significantly with each subsequent surgery. Multiple procedures increase the chance of encountering existing adhesions and creating new ones.
Type of Surgery	Open surgery (laparotomy) vs. minimally invasive surgery (laparoscopy).	Open procedures, due to larger incisions and greater tissue manipulation, have a much higher rate of adhesion formation than laparoscopic procedures.
Surgical Technique	Gentle handling of tissues, use of latex-free gloves, and minimizing heat and drying of organs.	Meticulous surgical technique, proper irrigation, and reduced exposure to foreign bodies can help minimize the inflammatory response and subsequent adhesion growth.
Underlying Inflammation	Conditions like endometriosis, PID, or Crohn's disease.	Chronic inflammation creates an environment ripe for scar tissue formation and can trigger adhesions even without surgery.
Genetic Predisposition	Certain genetic factors or a propensity for increased fibrosis.	While research is ongoing, some studies suggest that genetic variations may influence an individual's tendency to develop adhesions.

Managing and Preventing Adhesions

While it's impossible to completely prevent adhesions after surgery, certain strategies can minimize the risk.

Intraoperative Techniques

Minimally Invasive Surgery: Opting for laparoscopic or robotic-assisted surgery over open surgery can dramatically reduce adhesion risk.
Adhesion Barriers: During surgery, a surgeon can place a special film, gel, or spray between organs and tissues to act as a barrier. These barriers dissolve over time and help prevent surfaces from sticking together during the critical healing phase.
Careful Surgical Technique: Minimizing tissue damage, gentle handling of organs, and meticulous cleaning of blood clots are all best practices that can lower adhesion risk.

Postoperative Management

For individuals already experiencing symptomatic adhesions, surgical removal (adhesiolysis) is often the only option. However, this carries the risk of forming new adhesions. For those with chronic pain, physical therapy techniques like soft tissue mobilization may provide relief. A low-fiber or liquid diet may also be recommended for partial bowel obstructions. For comprehensive information on adhesions, including management strategies, refer to reputable sources like the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK).

Conclusion

Abdominal adhesions are triggered primarily by inflammation and injury, with abdominal surgery being the most significant culprit. Other causes range from infections like appendicitis to chronic conditions such as endometriosis. The formation process involves a complex imbalance in the body’s natural healing mechanisms, leading to persistent fibrous tissue. Understanding the various triggers and risk factors is the first step toward effective prevention and management. While adhesions can lead to serious complications like bowel obstruction and chronic pain, proactive measures and careful surgical techniques can help minimize their occurrence and impact.

Frequently Asked Questions

Yes, although surgery is the most common cause, abdominal adhesions can form due to other sources of inflammation or injury. These include infections like appendicitis or pelvic inflammatory disease (PID), certain inflammatory conditions like endometriosis or Crohn's disease, and abdominal trauma or radiation therapy.

Adhesions can cause problems at any point after surgery, from shortly after the procedure to many years later. As they can grow and tighten over time, a complication like a bowel obstruction may not appear until well into the future.

Laparoscopic, or minimally invasive, surgery significantly lowers the risk of adhesion formation compared to traditional open surgery (laparotomy). The smaller incisions cause less tissue trauma, which leads to less overall scarring.

While many adhesions are asymptomatic, those that cause problems may lead to symptoms including chronic or recurring abdominal pain, cramping, bloating, nausea, vomiting, constipation, or an inability to pass gas.

There is no definitive evidence that specific diets or exercise can prevent adhesion formation. However, some physical therapy techniques may help manage pain associated with adhesions, and a low-fiber diet can help manage symptoms of a partial bowel obstruction.

No, imaging studies like CT scans and MRIs generally cannot detect adhesions directly. However, they can show complications that result from adhesions, such as an intestinal blockage. Adhesions are most often confirmed during surgery.

The only way to treat problematic abdominal adhesions is through surgery to cut or remove the scar tissue, a procedure called adhesiolysis. However, more surgery carries the risk of forming new adhesions, so doctors often only recommend it when complications are severe.