Block 2 The Inguinal Region / Spermatic Cord Flashcards
Inguinal region
Contents of Inguinal Canal
Contents of Inguinal Canal:
- Deep ring - transversalis fascia (slit)
- Superficial ring– a triangle shaped opening in the aponeurosis of EO
- Roof: IO, TA
- Anterior wall: EO
- Floor: Inguinal / lacunar ligaments
- Posterior wall: Transversalis fascia and conjoint tendon
***Contains the spermatic cord - tubular extension of the layers of the abdominal wall into the scrotum that contains all structures passing between the testis and the abdomen (artery, vein, vas deferens etc.)
continuation of inguinal content
The peritoneal fossae
The peritoneal fossae
- Composes the Internal surface of anterolateral abdominal wall
- Depressions or pouches formed between various peritoneal folds; they may be the sites of internal hernias
- The peritoneal fossae between the umbilical folds are:
- Supravesicalfossae:
- Is between the median and the medial folds,
- It’s formed by reflection of the peritoneum onto the bladder, its level rises and falls with the filling of the bladder.
- Medial inguinal fossae:
- Is between medial and lateral folds, or the inguinal triangles (Hesselbach triangles)
- *potential site for direct inguinal hernia.
- Lateral inguinal fossae:
- Is lateral to lateral fold
- It includes deep inguinal ring and potential site for indirect inguinal hernia.
The Peritoneal Fossa
Identify the structures of the peritoneal fossa
Lateral and Median inguinal fossa, supravesicle fossa
Inguinal Region/ Hernias
Inguinal Region/ Hernias
- Hernias occur in both sexes
- Higher frequency in male (approximately 86%) due to passage of spermatic cord through inguinal canal, also because the testis are originally in the abdomen then migrate postnatally to the scrotum.
Descent of the testis from week 7 to birth.
- Testicles form before the second fetal month and starts to look like a testicle around the fourth fetal month.
- On the fourth fetal month it has migrated down from the kidney and lies next to the internal inguinal ring, where it remains until around the seventh fetal month.
- On the 7th fetal month the testicle, accompanied by a small peritoneal tube (process vaginalis, the so-called hernia sac), passes through internal ring, inguinal canal, and external ring to take its normal position in the scrotum (this can occur before or after birth.)
What Is An Undescended Testicle?
What Is An Undescended Testicle?
- The term “undescended testicle” is loosely applied to several different conditions:
- When a testicle is not in the normal scrotal location several possibilities exist: There may never have been a testicle (congenital absence=agenesis).
- The testis may have been lost before or just after birth due to torsion or vascular accident involving the testicular vessels.
- The testis may have not descended properly, but remains within the abdominal cavity. In older children, such abdominal testicles are abnormal in appearance, are not likely to be fertile, and have an increased chance of becoming malignant after puberty.
- The testis may have descended incompletely and may lie within the inguinal canal, at the external ring, or just outside of the scrotum.
- The testis may have come through the inguinal canal, but instead of then traveling down into scrotum, the testis passes into an ectopic location (usually a space under the skin in the groin, called the superficial pouch) where it is firmly anchored to the adjacent tissues. Unusual ectopic sites include the femoral region or the perineum.
Ligaments of the Inguinal canal region
Pectineal and Lacunar Ligament (respectively)
surface anatomy of inguinal ligament
Superficial inguinal ring and the aponeurosis of the external oblique – anterior wall
Aponeurosis of the external oblique and superficial, superficial inguinal ring
Transversus abdominis muscle roof inguinal canal
Transversus abdominis muscle roof inguinal canal
Deep inguinal ring and the transversalis fascia
Spermatic cord
- Contains structures running to and from testis
- Suspends the testis in the scrotum.
- It begins at the deep inguinal ring, lateral to the inferior epigastric vessels, passes through the inguinal canal, exits at the superficial inguinal ring, and ends in the scrotum at the posterior border of the testis.
- The constituents of the spermatic cord are:
- Ductus deferens or deferent duct: a muscular tube that conveys sperms from the epididymis to the ejaculatory duct.
- Testicular artery: arising from the aorta and supplying the testis and epididymis.
- Artery of the ductus deferens: arising from inferior vesical artery (which arises from internal iliac artery).
- Cremasteric artery: arising from inferior epigastric artery (which arises from external iliac artery).
- Pampiniform venous plexus: a network formed by up to 12 veins that converge superiorly as right or left testicular veins.
The coverings of the spermatic cord
The coverings of the spermatic cord is derived from anterolateral abdominal wall include the following:
- Internal spermatic fascia: derived from transversalis fascia
- Cremasteric fascia: derived from the fascia of both the superficial and deep surfaces of the internal oblique muscle
- External spermatic fascia: derived from the external oblique aponeurosis and its investing fascia.
- The cremasteric fascia: contains loops of cremaster muscle, which is formed by the lowermost fibers of internal oblique arising from the inguinal ligament. Resposible for the Cremastric reflex.
The Cremaster muscle (skeletal m. - somatic innervation – genital br. Genitofemeral n. from lumbar plexus) cremaster reflex draws the testis superiorly in the scrotum, particularly in response to cold. In a warm environment, such as hot bath, the cremaster relaxes and testis descends deeply in the scrotum.
The dartos muscle of the Scrotum (smooth muscle - sympathetic innervation – sacral splanchnics to sacral plexus to pudendal n. to perineal n.) dartos reflex acts with the cremaster muscle assisting in testicular elevation as it contracts the scrotal skin.
This is to keep the testis in a constant temperature (essential for spermatogenesis) one degree cooler than core temperature.
Although less well-developed the round ligament in female receives similar contributions from the abdominal wall.