An Overview of Abdominal Pain After Surgery

On occasion, abdominal surgery can sometimes lead to chronic abdominal nerve pain or chronic pelvic nerve pain. For people whose abdominal or pelvic nerves have been cut, stretched, or otherwise damaged during abdominal surgery (such as during an appendectomy, gynecological surgery, or hernia repair), the complication—referred to as surgically-induced neuropathic pain (SINP)—may not only be distressing but in some cases debilitating.

It is unclear how often this occurs, but researchers are starting to learn that nerve pain following surgery is much more common than once thought.

This can be concerning to read if you are planning to have surgery, but there are things you may be able to do to reduce the risk. At the same time, researchers are looking at ways to reduce the risk of SINP and to effectively treat it if it does occur.

Causes 

Abdominal surgery has been known on occasion to cause damage to the ilioinguinal, iliohypogastric, or genitofemoral nerves—each of which can cause postoperative pelvic nerve pain.

With that said, there is not always a simple relationship between nerve damage and SINP. There are a variety of reasons why SINP occurs. Among them:

• Pelvic nerves are close to incisional sites. During routine abdominal and pelvic surgeries, the iliohypogastric and ilioinguinal nerves are often directly in the line of fire. Due to anatomical differences between people, even the most skilled surgeons have the potential to sever these nerves.
• Anatomically, pelvic nerves are different in each person. Pelvic nerve structure can vary greatly from person to person. In some people, the nerves sit under the abdominal muscles. In other people, they may pass right through them. Some people have more pelvic nerve branches than others. Avoiding pelvic nerve damage during surgery is not easy when there are so many potential variations.
• Stretching pelvic nerves can also cause damage. You don’t have to have your pelvic nerves cut or nicked in order to suffer from chronic pelvic nerve pain. Sometimes, the nerves are stretched enough during surgery that damage is done.
• Pelvic nerves may become compressed after surgery. Nerve entrapment—in sutures, staples, or surgical mesh—can also lead to SINP during the course of abdominal or pelvic surgery.
• Pelvic nerves can become entrapped following surgery. A significant but under-recognized cause of chronic abdominal pain after surgery is cutaneous nerve entrapment. This occurs when nerves near the surface of the abdomen become entrapped as they pass through the rectus muscle. This is thought to be the cause of around 30% of cases of SINP after abdominal surgery.

In the same way that the exact cause of SINP can be unknown, it isn't clear what risk factors predispose a person to postoperative chronic nerve pain. Among the risk factors believed to be associated with SINP are preoperative pain, psychological factors (such as extreme anxiety), and the intensity of acute postoperative pain.

Diagnosis

The diagnosis of SINP is not always easy and, in some cases, doctors may not be able to pinpoint the cause. It can also be challenging because one person's experience of pain is often very different from another person's experience.

The diagnosis typically involves an in-office evaluation during which the doctor will ask the person a series of questions to better characterize the type of pain they are having (e.g., pins-and-needles, stabbing, burning).

To subjectively establish the level of pain a person is experiencing, the doctor may perform a simple survey called a neuropathic pain scale (NPS), scoring symptoms on a scale of 0 to 10.

In addition, imaging studies may be ordered to check for nerve injury, including computed tomography (CT) or magnetic resonance imaging (MRI) scans. Newer imaging technologies are being developed to evaluate nerves on a cellular and even molecular level.

Treatment

There are several possible treatments for chronic pelvic nerve pain that doesn't resolve on its own following surgery.

Medications

Most doctors will recommend certain medications for chronic neuropathic pain. The most commonly prescribed drugs are tricyclic antidepressants and anticonvulsants such as Neurontin (gabapentin).

Newer medications such as Lyrica (pregabalin) have also been effective for some people. Although these medications weren't originally developed for treating pain, they have been found to relieve pain in some conditions.

It is important to note that antidepressants prescribed for chronic pain are thought to modulate pain receptors in the brain. In other words, doctors do not prescribe these drugs because they believe "your pain is in your head."

Procedures

In addition to medication, there are certain procedures that may help relieve chronic nerve pain following surgery:

• Nerve blocks: Nerve blocks, or neural blockades, are procedures that can help prevent or manage many different types of pain. They often involve injections of medicines that block pain signals from specific nerves.
• TENS: Transcutaneous electrical nerve stimulation (TENS) is a therapy that uses low-voltage electrical currents to provide pain relief. A TENS unit consists of a battery-powered device that delivers electrical impulses through electrodes placed on the skin. TENS has helped some people cope with intractable (treatment-resistant) nerve pain.
• Surgery: In specific cases, surgery may be explored to reconnect severed nerves. This may involve a nerve repair (in which the damaged section of nerve tissue is removed and the healthy ends are reattached) or a nerve graft (in which a piece of nerve from another part of the body is implanted at the site of the damage).

Prevention

Though researchers have a long way to go in determining the best ways to prevent SINP, there are several things that may help reduce a person's risk of the all-too-common complication.

Since the severity of acute postoperative pain is strongly linked with the risk for chronic pain, aggressive treatment of postoperative pain is considered imperative. Studies have shown that the aggressive, up-front management of pain following surgery corresponds to better pain control down the line.

In other words, you need to inform your doctor of any pain you experience after surgery and not dismiss it as something "you'll get over."

Coping

Most studies suggest that the best treatment of nerve pain is a combination of medications, medical therapies, and lifestyle measures. There are several things you can do to cope as you explore the most effective means of treatment:

• Keep a pain journal. Chronicling your experience can be very helpful when dealing with chronic pain. Not only may it help you further understand your pain so that you can share your symptoms with your doctor, but it can also be an effective way to determine what works and what doesn't work in managing your symptoms.
• Explore mind-body therapies. From meditation to yoga, mind-body therapies may not only decrease your pain but can decrease the stress in your life that exacerbates your pain.
• Seek support. Talking with others about your experiences often helps relieves the stress of "suffering in silence." Working with a chronic pain support group also provides you the means to ask questions, seek referrals, or share experiences with others who fully understand what you are going through.

A Word From Verywell

If you are concerned about pain as you approach a scheduled surgery, keep in mind that the majority of people who undergo abdominal surgery do not experience SINP.

As more and more research becomes available, surgeons are utilizing more advanced techniques to avoid damage to pelvic nerves during abdominal and pelvic surgery. To make an informed choice about a surgical procedure, ask as many questions as you can and seek a second opinion if needed.