A 36-year-old man presents to his physician complaining of right scrotal swelling. He states that the swelling has been present for 1 week. He initially noticed the swelling sholy after moving furniture for his new living room. He denies any nausea, vomiting, change in bowel habits, abdominal pain, or urinary tract symptoms. He has no other significant medical or surgical history. On examination, he has an enlarged right hemi-scrotum with a mass that appears to be originating at the level of the external inguinal ring. With the patient completely relaxed, the physician is able to reduce the mass by pushing it back through the external inguinal ring. With the mass reduced, the physician instructs the patient to perform a Valsalva maneuver, upon which a protrusion is felt at the external inguinal ring. Once the mass is reduced, the testicle appears normal in size and consistency. Which of the following pathological processes might cause the patient's underlying condition to occur in an infant?
The pathologic process that causes hernias is different in neonates and infants than in an adult. Embryologically, in the seventh week, the testes begin descending from their location at the 10th thoracic level into the scrotum. After the eighth week, a peritoneal evagination called the processus vaginalis forms just anterior to the gubernaculum. The gubernaculum is a condensation of peritoneum that attaches superiorly to the gonad and inferiorly to the fascia that is developing between the external and internal oblique muscles in the region of the labioscrotal swellings. The processus vaginalis pushes out as a "sock-like" extension into the transversalis fascia, the internal oblique muscle, and the external oblique muscle, thus forming the inguinal canal. After the processus vaginalis has evaginated into the scrotum, the gubernaculum shoen and simply pull the gonads through the canal. Within the first year after bih, the superior poion of the processus vaginalis is usually obliterated, leaving only a distal remnant sac, the tunica vaginalis, which lies anterior to the testis. During infancy, this sac wraps around most of the testis. Its lumen is normally collapsed, but under pathologic conditions it may fill with serous secretions, forming a testicular hydrocele. If the processus vaginalis remains patent, a connection between the abdominal cavity and scrotal sac will occur. Loops of intestine may herniate into this processus, resulting in an indirect inguinal hernia. Note: In adults, hernias are caused by a protrusion of a structure, usually intestine, through a tissue that normally contains it. Direct inguinal hernias occur through the floor of the inguinal canal separate from the spermatic cord. Direct inguinal hernias occur because of a breakdown of the transversus abdominis aponeurosis and transversalis fascia. An indirect inguinal hernia occurs through the internal inguinal ring in a protrusion of peritoneum along the spermatic cord in the internal spermatic fascia. Therefore, a large indirect inguinal hernia will descend into the scrotum along the spermatic cord. Spigelian hernias are rare and occur due to a weakness in the linea semilunaris, which is located at the lateral margin of the rectus sheath. Ref: Sundaram S.S., Hoffenberg E.J., Kramer R.E., Sondheimer J.M., Furuta G.T. (2012). Chapter 21. Gastrointestinal Tract. In W.W. Hay, Jr., M.J. Levin, R.R. Deterding, J.J. Ross, J.M. Sondheimer (Eds), CURRENT Diagnosis & Treatment: Pediatrics, 21e.
Defect in the floor of the inguinal canal
Defect in the internal inguinal ring
Defect in the linea semilunaris
Patent processus vaginalis