giovedì 25 aprile 2019
Cardiosplanchnology
The Reproductive System
INGUINAL CANAL
It is a slit-like passage extending just above and parallel to the
inguinal ligament. It begins at the deep inguinal ring and
continues for approximately 4 cm, ending at the superficial
inguinal ring. Contents of the canal are the spermatic cord in
men and the round ligament of the uterus and genital branch of
genito-femoral nerve in women. The ilio-inguinal nerve passes
through part of the canal, exiting through the superficial inguinal
ring with the other contents.
The deep inguinal ring is localised between the anterior superior
iliac spine and the pubic symphisis. It is the beginning of the
tubular evagination of the transversalis fascia that forms the
internal spermatic fascia, covering the spermatic cord or the
round ligament.
The superficial inguinal ring is superior to the pubic tubercle. It is a triangular opening in the
aponeurosis of the external oblique. It is the beginning of the tubular evagination of the aponeurosis of the
external oblique onto the structures emerging form it. This continuation of tissue over the spermatic cord is
known as the external spermatic fascia.
The anterior wall of the inguinal canal is formed entirely by the aponeurosis of the external oblique
muscle. It is reinforced laterally by the lower fibres of the internal oblique, which additionally covers the
deep inguinal ring. Moreover, it contributes to the cremasteric fascia, which contains the cremasteric
muscle.
The posterior wall is formed by the transversalis fascia and
is reinforced by the conjoint tendon (inguinal falx), which
is given by the combined insertion of the transversus
abdominis and internal oblique muscle into the pubic crest
and pectineal line.
The roof is constituted by the arching fibres of the
transversus abdominis and internal oblique muscles, while
the floor is formed by the medial half of the inguinal
ligament. This lower free margin of the external oblique aponeurosis forms a gutter on which the contents
of the inguinal canal are positioned. The lacunar ligament reinforces most of the medial part of the gutter.
The spermatic cord begins at the deep inguinal ring and consists of structures passing between the
abdomino-pelvic cavity and the testis, including the:
• Ductus deferens
• Artery to the ductus deference
• Testicular artery
1
, giovedì 25 aprile 2019
• Pampiniform plexus of veins
• Cremaster artery and vein
• Genital branch of the genitofemoral nerve
• Sympathetic and visceral afferent nerve fibres
• Lymphatics
• Remnants of the processus vaginalis
All of these structures enter the deep inguinal ring, proceed
down the inguinal canal and exit from the superficial inguinal
ring, acquiring the three covering fascias during the journey:
1. Spermatic fascia, deepest layer, from transversalis fascia
2. Cremasteric fascia, middle, from internal oblique.
3. External spermatic fascia, from aponeurosis of external oblique.
The round ligament of the uterus is a cord like structure going from the uterus through the deep inguinal
ring. It passes down the inguinal canal and exits from the superficial inguinal ring, changing into few
strands of tissue during its course. These attach to the connective tissue of the labia majora. It acquires
the same coverings as the spermatic cord. The round ligament of the uterus originates from the
gubernaculum in the fetus, extending from the ovary to the labioscrotal swelling.
Reproductive System in Men
The major components on each side are the testis, epididymis, ductus deferens and ejaculatory duct,
while in the midline we can find the urethra and penis. In addition, there are three accessory glands, a
single prostate, a pair of seminal vesicles and a pair of bulbourethral glands.
The testes develop high on the posterior abdominal wall, then descend before birth through the inguinal
canal into the scrotum of the perineum. During descent, they carry their vessels, lymphatics, nerves, and
principal drainage ducts, the ductus deferens. The lymph drainage is therefore to the lateral aortic or
lumbar nodes and pre-aortic nodes in the abdomen. They are ellipsoidal in shape, enclosed within the end
of an elongated musculo-fascial pouch, continuous with the anterior abdominal wall and projecting into the
scrotum. The spermatic cord connects the pouch with
the abdominal wall. Testes are covered by a closed
sac of peritoneum, the tunica vaginalis, originally
connected to the abdominal fascia. After descendant,
the connection is interrupted, leaving a fibrous
remnant. Each testis is composed of seminiferous
tubules and interstitial tissue, surrounded by a thick
connective tissue capsule, the tunica albuginea. Its
inner part is the tunica vasculosa, composed of loose
connective tissue and rich in blood vessels. Each
testis is divided by connecive tissue septa projecting
from the capsule into about 250 lobules, each packed
with seminiferous tubules and stroma. Overall there are 400 to 600 highly coiled seminiferous tubules, in
which spermatozoa are produced. The ends of the tubules are modified at each end to become straight
tubules, and connect to a collecting chamber, the rete testis, a complex series of interconnecting
2
Cardiosplanchnology
The Reproductive System
INGUINAL CANAL
It is a slit-like passage extending just above and parallel to the
inguinal ligament. It begins at the deep inguinal ring and
continues for approximately 4 cm, ending at the superficial
inguinal ring. Contents of the canal are the spermatic cord in
men and the round ligament of the uterus and genital branch of
genito-femoral nerve in women. The ilio-inguinal nerve passes
through part of the canal, exiting through the superficial inguinal
ring with the other contents.
The deep inguinal ring is localised between the anterior superior
iliac spine and the pubic symphisis. It is the beginning of the
tubular evagination of the transversalis fascia that forms the
internal spermatic fascia, covering the spermatic cord or the
round ligament.
The superficial inguinal ring is superior to the pubic tubercle. It is a triangular opening in the
aponeurosis of the external oblique. It is the beginning of the tubular evagination of the aponeurosis of the
external oblique onto the structures emerging form it. This continuation of tissue over the spermatic cord is
known as the external spermatic fascia.
The anterior wall of the inguinal canal is formed entirely by the aponeurosis of the external oblique
muscle. It is reinforced laterally by the lower fibres of the internal oblique, which additionally covers the
deep inguinal ring. Moreover, it contributes to the cremasteric fascia, which contains the cremasteric
muscle.
The posterior wall is formed by the transversalis fascia and
is reinforced by the conjoint tendon (inguinal falx), which
is given by the combined insertion of the transversus
abdominis and internal oblique muscle into the pubic crest
and pectineal line.
The roof is constituted by the arching fibres of the
transversus abdominis and internal oblique muscles, while
the floor is formed by the medial half of the inguinal
ligament. This lower free margin of the external oblique aponeurosis forms a gutter on which the contents
of the inguinal canal are positioned. The lacunar ligament reinforces most of the medial part of the gutter.
The spermatic cord begins at the deep inguinal ring and consists of structures passing between the
abdomino-pelvic cavity and the testis, including the:
• Ductus deferens
• Artery to the ductus deference
• Testicular artery
1
, giovedì 25 aprile 2019
• Pampiniform plexus of veins
• Cremaster artery and vein
• Genital branch of the genitofemoral nerve
• Sympathetic and visceral afferent nerve fibres
• Lymphatics
• Remnants of the processus vaginalis
All of these structures enter the deep inguinal ring, proceed
down the inguinal canal and exit from the superficial inguinal
ring, acquiring the three covering fascias during the journey:
1. Spermatic fascia, deepest layer, from transversalis fascia
2. Cremasteric fascia, middle, from internal oblique.
3. External spermatic fascia, from aponeurosis of external oblique.
The round ligament of the uterus is a cord like structure going from the uterus through the deep inguinal
ring. It passes down the inguinal canal and exits from the superficial inguinal ring, changing into few
strands of tissue during its course. These attach to the connective tissue of the labia majora. It acquires
the same coverings as the spermatic cord. The round ligament of the uterus originates from the
gubernaculum in the fetus, extending from the ovary to the labioscrotal swelling.
Reproductive System in Men
The major components on each side are the testis, epididymis, ductus deferens and ejaculatory duct,
while in the midline we can find the urethra and penis. In addition, there are three accessory glands, a
single prostate, a pair of seminal vesicles and a pair of bulbourethral glands.
The testes develop high on the posterior abdominal wall, then descend before birth through the inguinal
canal into the scrotum of the perineum. During descent, they carry their vessels, lymphatics, nerves, and
principal drainage ducts, the ductus deferens. The lymph drainage is therefore to the lateral aortic or
lumbar nodes and pre-aortic nodes in the abdomen. They are ellipsoidal in shape, enclosed within the end
of an elongated musculo-fascial pouch, continuous with the anterior abdominal wall and projecting into the
scrotum. The spermatic cord connects the pouch with
the abdominal wall. Testes are covered by a closed
sac of peritoneum, the tunica vaginalis, originally
connected to the abdominal fascia. After descendant,
the connection is interrupted, leaving a fibrous
remnant. Each testis is composed of seminiferous
tubules and interstitial tissue, surrounded by a thick
connective tissue capsule, the tunica albuginea. Its
inner part is the tunica vasculosa, composed of loose
connective tissue and rich in blood vessels. Each
testis is divided by connecive tissue septa projecting
from the capsule into about 250 lobules, each packed
with seminiferous tubules and stroma. Overall there are 400 to 600 highly coiled seminiferous tubules, in
which spermatozoa are produced. The ends of the tubules are modified at each end to become straight
tubules, and connect to a collecting chamber, the rete testis, a complex series of interconnecting
2
