By Mark B. Wilkiemeyer, M.D., FACS
Abdominal wall hernia, simply defined as a space or gap in the abdominal wall, is one of the most common complaints seen by the practicing general surgeon. Literature tends to focus on management of hernia once it is identified and classified, but this ignores the necessary diagnostic steps to correctly classify the location of the hernia. The history and physical examination provides many of the clues necessary for proper hernia identification and subsequent classification and management.
History: Use the OLD CARTS Mnemonic
Onset can provide context for hernia identification and management. The sudden appearance of a bulge or the gradual “coming and going” of vague pain will help guide the physician towards an accurate diagnosis and help triage the patient. Sudden unrelenting painful bulges would prompt much more rapid assessment and surgical treatment than the slow, gradual onset of discomfort.
Location is an important component for hernia management. The patient’s subjective reporting of location of pain and/or a bulge provides the starting point for hernia identification. Incisional, umbilical and inguinal/groin hernias can be quickly localized by patient complaint.
Duration is less specific for hernia identification. As hernias can have long durations and gradually become more symptomatic, the duration of the hernia rarely is the most important factor in classification or management strategies.
Character of the pain can give clues to the hernia contents (bowel more crampy, preperitoneal fat sharp localized pain, omentum sharp but more generalized in location). As hernias can be painless but still bothersome, the character of the hernia symptoms should be noted but are not essential to initial diagnosis. It may prompt further diagnostic workup or more urgent management.
Aggravating factors and relieving factors will generally be related to abdominal wall musculature utilization and rest. Increases in intra-abdominal pressure through coughing, sneezing or exercise will commonly exacerbate discomfort.
Radiation of pain can provide additional clues as to the contents of the hernia.
Timing or temporal factors will sometimes help with hernia diagnosis and management but are often associated with aggravating factors and won’t often distinguish hernias alone.
Severity of symptoms will prompt urgent or elective management but rarely give additional information about the hernia itself. However, severe unrelenting crampy pain can point to a strangulated hernia containing ischemic or compromised bowel.
Physical Exam: Experience Counts
The comprehensive physical exam remains critical to assessment and management of the patient with a hernia complaint. Experience with examination improves diagnostic accuracy and likely reduces the use of imaging.
Generally, the hernia should be classified as “reducible” or “incarcerated”; this will assist in determining timing of repair if needed. Incarcerated hernias, or hernias thought to contain compromised viscera, will generally be explored and repaired as a surgical emergency. Conversely, the reducible hernia is often managed on an elective basis. Chronically incarcerated but minimally symptomatic umbilical or incisional hernias are exceptions to this rule, where severity of symptoms will help us make recommendations for urgency of surgical treatment.
Examination will include multiple positions (standing and supine) along with multiple degrees of intra-abdominal pressure. A relaxed abdominal wall can allow the physician to palpate the fascial edges of the hernia defect; a Valsalva maneuver provides “proof” of hernia bulge and possibly clues as to the contents.
Thorough inspection of overlying skin incisions and anatomic landmarks help improve accuracy of diagnosis and management; for example, umbilical hernias and incisional hernias at the umbilicus can provide vastly different challenges during surgical management.
Partial thickness abdominal wall hernias can provide diagnostic confusion; if no “hole” is present in the most superficial fascial layer, then a vague bulge may be identified but a focal fascial defect may be absent. We see this with lateral trocar site incisional hernias and lower lateral abdominal wall Spigelian hernias; generally, hernias in or near the midline will not cause this confusion.
One common point of confusion is the presence of rectus diastasis. This is not a true hernia but is the separation of the rectus muscles due to chronic abdominal distention. This separation is commonly secondary to truncal obesity or multiple pregnancies. This presents as a vertical abdominal bulge above the umbilicus which appears when doing a sit up. This does not represent a true hernia and therefore does not require repair unless there are cosmetic concerns.
Imaging When Necessary
Cross-sectional imaging of the abdomen and pelvis can provide assistance when history and physical examination are not sufficient to confirm diagnosis and accurate localization of an abdominal wall hernia. They are not necessary to make a diagnosis or recommendation for surgery, and can sometimes cloud the issue if there is no obvious hernia seen but history and physical are clearly pointing towards surgical management.
Cross-sectional imaging of the abdomen and pelvis can incidentally identify abdominal wall defects. When identified these should be evaluated by an experienced surgeon.
Surgical Management of Abdominal Wall Hernias
In general, symptomatic hernias will be repaired in suitable surgical candidates. Regional anesthesia is available to reduce anesthesia risk, but care should be given to prioritize the ability of the surgeon to produce a durable repair. If regional anesthesia alone is insufficient for reduction and proper repair of the hernia, then the surgical risk outweighs benefit and the procedure should be carefully reconsidered.
The main surgical principals of hernia repair are reduction of the hernia contents, clear identification of the borders of the defect, followed by closure of the defect with as little tension as possible. Mesh is commonly used to reinforce and add durability to the repair. The location of the mesh reinforcement has changed over the years. Current trends in hernia repair place the mesh within the layers of the abdominal wall as opposed to inside the peritoneal cavity or above the fascia.
Minimally invasive surgical techniques for abdominal wall hernias include laparoscopic and robotic approaches. Traditional repairs are done with open incisions. Each of these has benefits and drawbacks; nonetheless, the patient is well served by meeting with surgeons who can offer a wide variety of treatment options.
Mesh is used to reduce the risk of recurrence. In some cases mesh is required to “bridge” a defect that cannot be closed with suture, although this is less than ideal. The use of mesh can increase the risk of complications, but its value in adding durability to the repair generally outweighs these concerns.
Common materials used to manufacture synthetic mesh include polypropylene and polyester. In recent years biologic meshes have become common with porcine- and bovine-derived materials being used in certain complicated and high-risk situations. Generally these biologic materials are thought to carry less risk of chronic infection but are much more expensive than synthetic mesh and are commonly perceived as a less durable over the long term.
The ideal hernia repair continues to be an evolving science. Advances in technique and options for abdominal reinforcement create an exciting and changing landscape for patients and general surgeons.
Dr. Wilkiemeyer grew up in Atlanta and attended Vanderbilt University, then went on to attend Tulane University School of Medicine in New Orleans, where he graduated Alpha Omega Alpha in 1998 as a Doctor of Medicine. He trained in General Surgery at University of Texas Southwestern, subsequently completing a fellowship in laparoscopic surgery at the Duke University Medical Center. He lives in
Atlanta with his wife, Claire Dudley Wilkiemeyer, M.D., and their two children.