The bony attachments of the inguinal region counteract abdominal thrust, and the presence of natural gaps that exist in this region may allow peritoneal diverticula to externalize and appear as hernias. Inguinal hernia sac, which represents approximately 95 % of abdominal wall hernias in the male and 50 % in the female, has the highest incidence of onset in the 1st year oflife followed by a second peak between the ages of 16 and 20. Hernial sac traverses the entire length of the inguinal canal from the deep to the superficial inguinal ring. It may al so pursue a much shorter path, passing only through the superficial inguinal ring. The hernial sac appears above and medial to the pubic tubercle. Herniation that follows the entire length of the inguinal canal is an indirect inguinal hernia; it commonly results from persistent processus vaginalis and therefore is known as an indirect (congenital) inguinal hernia. The Hessert's triangle, formed by the intersection of the aponeurosis of the internal oblique and transverse aponeuroses and the rectus sheath, may play an important role in the etiology of the inguinal hernia . This triangle maybe occluded upon contraction of the abdominal muscles and by their movement toward the inguinal ligament. However, when a larger triangle exists, the occlusion cannot be complete, a condition that leads to hernia-tion.
Inguinal hernia is often asymptomatic, but some patients, particularly the middle-aged and elderly, experience aching pain in the lower abdominal quadrants that radiates to the medial thigh. Others relate the sudden occurrence of the condition to strenuous activity. Patients may report an intermittent, reducible or nonreducible groin mass. In infants, it is thought that thickening of the spermatic cord at the superficial inguinal ring on one side is an important sign of an inguinal hernia. The infrequent occurrence of inguinal hernia in the female is commonly attributed to the small size of the superficial inguinal ring and the fatty composition of the major labium.
Laparoscopic procedures in the repair of inguinal hernia have produced an increase in the frequency of debilitating neuropathies, most notably those of the ge-nitofemoral, ilioinguinal, and lateral femoral cutaneous nerves. The highly variable course of the lateral femoral cutaneous nerve and its branches within the pelvis may directly account for this complication . Aszman  demonstrated five different types of relationships of the lateral femoral cutaneous nerve to soft tissue and bony structures. Four percent (type A) maintained a course posterior to the anterior superior iliac spine and across the iliac crest; 27% (type B) traveled anterior to the anterior superior iliac spine, within the inguinal ligament and superficial to the origin of the sartorius muscle. In 23 % (type C) the nerve ran medial to the anterior superior iliac spine within the tendinous origin of the sartorius, and in 26 % (type D) the nerve was found deep to the inguinal ligament between the iliopsoas fascia and the sartorius muscle. In the same study 20% (type E) pursued a course deep to the inguinal ligament within the soft tissue anterior to the iliopsoas muscle, joining the femoral branch of the ge-nitofemoral nerve. This study has suggested that the lateral femoral cutaneous nerve is most prone to damage when it pursues a course indicated by types A, B, or C.
In a study conducted by Rosenberg et al. , the course of the genitofemoral, lateral femoral, and ilioin-
guinal nerves and their relationships to the deep inguinal ring, iliopubic tract, and anterior superior iliac spine were carefully examined. The findings indicate that both branches of the genitofemoral nerve penetrate the abdominal wall lateral to the deep inguinal ring and cranial to the iliopubic tract. The ilioinguinal and lateral femoral cutaneous nerves pursued a course immediately lateral to the anterior superior iliac spine. It concluded that placement of staples either cranial to the iliopubic tract or lateral to the anterior superior iliac spine is likely to produce injury to these nerves.
Hospodar et al.  examined, in a series of cadaveric pelvis, the lateral femoral cutaneous nerve with respect to the ilioinguinal surgical dissection. In approximately 10% of the pelves examined the lateral femoral cutaneous nerve was found either within a half-centimeter of the iliopubic tract or in the vertical plane of the anterior superior iliac spine. These are the principal anchoring sites for mesh in laparascopic hernial repair. In another study, the lateral femoral cutaneous nerve was most commonly found at 10-15 mm from the anterior superior iliac spine (ASIS), and as far medially as 46 mm. Because of this variation, careful dissection medial to the ASIS maybe essential to locate the nerve.
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