In the middle of the night, a 16 year old male named Shane is brought to the emergency department by his parents after waking up with severe pain in his right scrotum. Shane does not recall any traumatic events prior to the onset of his symptoms. On physical examination, the scrotum appears swollen; in addition, you notice that the pain is worsened with elevation of the scrotum, and stroking of the right inner thigh does not result in elevation of the right testis.
Later that day, you meet a 28 year old male called Elias, who comes in for a fertility evaluation. Elias and his wife have been trying to conceive for two years without success. Recently, Elias has also noticed an enlargement and a feeling of pressure in his left scrotum. On physical examination, you palpate a mass along the spermatic cord that feels like a “bag of worms”.
Based on the initial presentation, both Shane and Elias seem to have some form of testicular and scrotal condition. Now, for your exams, remember that the testes begin their development in the abdominal cavity, within the peritoneum. During the third trimester of pregnancy, the testes usually begin to descend into the pelvis via the inguinal canal, and ultimately settle in the scrotum. This needs to occur because sperm can't survive at body temperature, and that’s a high yield fact!
Now, as the testes gradually migrate, a peritoneal outpouching called the processus vaginalis forms, and pulls the layers of the anterolateral abdominal wall with it into the developing scrotum. The testes then follow the processus vaginalis into the scrotum. After the testes have descended to the scrotum, the processus vaginalis closes up. Within the scrotum, each testis remains partially covered by an extension of the peritoneum, which forms a serous layer called the tunica vaginalis. The only part that’s not covered by the tunica vaginalis is where the testes are attached to the epididymis and spermatic cord.