Abdominal wall hernias account for 4.7 million ambulatory care visits each year, more than 600,000 of which are inguinal hernias that undergo repair [2]. Inguinal hernias present with a 9:1 male predominance, are more common on the right, and are most commonly in the 40–59 year age group. Indirect hernias are twice as likely to be present when compared with direct hernias [3]. In women, as in men, indirect hernias are the most common inguinal hernia. Femoral hernias, however, are relatively more common in women when compared to men, comprising 20 % of all groin hernias in women [1].

Other pertinent hernias that could contribute to groin pain include Spigelian hernias, obturator hernias, and Pantaloon hernias. Pantaloon hernias occur when there is both a direct and indirect hernia component. A Spigelian hernia is usually small and presents with bowel incarceration or strangulation in approximately 25 % of cases [1]. This defect is seen as a protrusion through the transversals fascia lateral to the edge of the rectus muscle, medial to the Spigelian line, and midway between the umbilicus and pubis at the level of the semicircular line of Douglas [1]. The obturator hernia is rare and often presents as a surgical emergency as a peritoneal pouch with accompanying small bowel, which may be incarcerated or strangulated as it follows the course of the obturator vessels through the obturator fossa. Such hernias are five times more common in women than men and most often present between the ages of 50 and 90 [1].

Physical exam should be performed with the patient in the upright position. It should include a close inspection of the inguinal and femoral regions for visible bulges. Palpation of the region should include a Valsalva maneuver from the patient in an attempt to elicit a palpable herniation [2]. If physical exam is inconclusive for inguinal hernia, there are several radiographic modalities such as CT, MRI, and ultrasound that can be utilized; these are discussed in further depth in the occult inguinal hernia section.

The main disadvantage of unilateral laparoscopic repair involves the long learning curve in mastering the delicate laparoscopic dissection techniques and groin anatomy. It has been said that one becomes confident with the procedure with 80 cases and mastery comes with 250 cases [7]. Other disadvantages include the need for general anesthesia, and the complications with laparoscopic repair, though rare, can also be more serious, as they include vascular or visceral injury [8].

With unilateral repair it is still, therefore, up for debate whether to perform laparoscopic or open repair. This should depend on surgeon preference and comfort level. The type of repair also depends on individual patient needs, including if the patient has any contraindications for laparoscopic surgery or general anesthesia, in which case open herniorrhaphy would be preferred.

In those who present with groin pain, aching, discomfort, or intermittent groin swelling with equivocal or negative physical exam findings, it is important to consider occult inguinal hernia as a possible diagnosis [10]. The definition of occult inguinal hernia is not well defined in the literature, and it is often left open to a wide range of interpretations. In a 2013 study by van den Heuvel et al., there is a distinction made between true occult inguinal hernia, which is repairable at the time of surgery, and incipient hernia, which defines a small defect with a shallow hernia sac in which there is no herniation of intra-abdominal contents [11]. In this study, they found that the incidence of a contralateral “occult” inguinal hernia was 13 % when TAPP repair of a clinically palpable inguinal hernia was performed. Of these, 8 % were true occult hernias and 5 % were incipient. True occult hernias were repaired at the time of exploration, and the incipient hernias were followed closely, 21 % of which became symptomatic, requiring additional surgery.

In a 2012 study by Garvey, it was found that of those with symptoms suggestive of hernia, in the absence of clear physical exam findings, 33 % of patients who underwent CT examination were found to have an occult inguinal hernia. This was then confirmed in the operating room with 94 % accuracy. As discussed below, CT may not be the best imaging modality, but this figure of 33 % serves to show the approximate incidence of those with occult inguinal hernia who present with groin pain [10].

In discussing occult hernia, women are an important population to consider. Groin pain can be a common symptom in women with a differential diagnosis similar to men, including urologic, gastrointestinal, or musculoskeletal causes with the addition of gynecologic disorders [12]. The population of women with chronic pelvic pain is also important to consider, as pelvic pain often includes the inguinal region [13]. Hernias are often smaller in females, leading to an undetectable clinical impulse on exam due to the absence of a processes vaginalis [14]. Of the approximately 20 million hernia repairs performed to date, only 6–8 % of these have been performed in women. It has been suggested, however, that occult hernias may be relatively common in women suffering from groin pain, especially those who experience worsening of symptoms with activity. Given the normal physical exam findings, these women can often have a prolonged symptomatic period before a correct diagnosis of groin hernia is achieved. As in men, it is important to consider and diagnose a hernia before it presents as a surgical emergency [15].