Consultation with the Specialist
Diagnosis of Inguinal Hernia and Hydrocele
Moritz M. Ziegler MD1
1 Director, Pediatric Surgery and Surgeon-in-Chief, Children's Hospital Medical Center, Cincinnati, OH.
Inguinal herniorrhaphy is the most common operative procedure performed by the pediatric surgeon. Inguinal hernias, indirect by classification in the majority of cases because they originate at the deep inguinal ring lateral to the inferior epigastric artery and vein, are common. The incidence is 1% to 5% in a large pediatric series and may be as prevalent as 7% to 30% in newborns weighing less than 1000 g. The incidence in males outnumbers that in females 8:1 to 10:1, and 50% to 60% of hernias are right-sided, 30% are left-sided, and 10% to 20% are bilateral. There often is a family history of inguinal hernias. The term "congenital" is applied to the etiology of pediatric inguinal hernias based on the pathophysiology of patency of the processus vaginalis.
Embryology and Inguinal Hernias
After the appearance of the gonads along the ventromedial aspect of the urogenital ridge by the sixth week of gestation, differential growth brings the gonads to the internal inguinal ring by the twelfth week. The processus vaginalis in the male (or the canal of Nuck in the female) begins at this time as a peritoneal outpouching at the deep inguinal ring. As the testes move from their internal location to begin their external descent during the twenty-eighth to thirty-sixth weeks of gestation, the processus vaginalis is pushed ahead into the scrotum.
