Inguinal Region and Descent of the Gonads Flashcards
What are the 8 layers of the anterolateral abdominal wall?
- ) Skin
- ) Superficial Fascia
- ) External oblique
- ) Internal oblique
- ) Transverse abdominus
- ) Transverse Fascia
- ) Extraperitoneal
- ) Parietal Peritoneum
What are the two layers of the superficial fascia?
- ) Camper’s Fascia
2. ) Scarpa’s Fascia
The outer fatty layer of superficial fascia
Camper’s Fascia
The inner fibrous layer of superficial fascia
Scarpa’s Fascia
What are the three parts of the external oblique layer?
- ) External oblique muscle
- ) External oblique Aponeurosis
- ) External oblique Fascia
What are the three parts of the internal oblique layer?
- ) Internal oblique muscle
- ) Internal oblique Aponeurosis
- ) Internal oblique Fascia
What are the three parts of the transverse abdominis layer?
- ) Muscle
- ) Aponeurosis
- ) Fascia
The transversalis fascia is also known as the
Endoabdominal fascia
The Scarpa’s fascia of the anterior abdomnal wall is continuous inferiorly as the
- ) Dartos fascia of scrota and penis
2. ) Colle’s fascia of perineum
In the anterior midline, and covered by anterior and posterior rectus sheaths
Rectus Abdominis muscles
Splits at the lateral border of the rectus abdominus, above the arcuate line (upper three fourths)
Internal oblique aponeurosis
Formed by the external oblique aponeurosis and the anterior lamina of the internal oblique aponeurosis
Anterior rectus sheath
Formed by the posterior lamina of the internal oblique
aponeurosis and the transversus abdominis aponeurosis
Posterior rectus sheath
Below the arcuate line (lower one-fourth) the internal oblique aponeurosis does not split at the lateral border of the muscle and all three aponeuroses pass
Anterior to the rectus abdominus
Below the arcuate line (lower one-fourth) the internal oblique aponeurosis does not split at the lateral border of the muscle and all three aponeuroses pass anterior to the rectus abdominis to form the
Anterior sheath
There is no posterior sheath, and the muscle lies directly against the
Transversalis fascia
The inferior epigastric vessels lie between the
Posterior rectus sheath and the rectus abdominis muscle
The inferior epigastric vessels gain entrance to the rectus sheath at the
Arcuate line
Below the arcuate line, the inferior epigastric vessels lie between the
Transversalis fascia and rectus abdominis
The inferior epigastric vessels anastomose with the
Superior epigastric vessels
The downward continuation of the internal thoracic vessels
Superior epigastric vessels
Thus, there is an anastomotic pathway between
branches of the subclavian vessels (internal thoracic) and branches of the
External illiac vessels (inferior epigastric)
The external oblique aponeurosis inserts onto the
Illiac crest and pubic crest
The external oblique aponeurosis has no bony attachment between the
Anterior superior illiac spine and the pubic tubercle
The external oblique aponeurosis folds under on itself between the
Anterior superior illiac spine and the pubic tubercle
The edge of this fold is the
Inguinal ligament
The lateral 2/3 of the folded under portion of the aponeurosis serves as an attachment for the
Internal oblique muscle
Has no muscle attached to it
Medial 1/3 of folded under portion
The medial 1/3 of the folded under portion of the external oblique aponeurosis has no muscle attached to it. This leaves a gap for what to pass through?
Spermatic cord (males) or round ligament of the uterus (females)
This gap (intermediate inguinal ring) is between the inguinal ligament and the lower edge of the internal oblique muscle, called the
Falx inguinals
The medial portion of the internal oblique aponeurosis and the transversus abdominis aponeurosis are fused into a single tendon called the
Conjoint Tendon
The conjoint tendon is the medial continuation of the
Falx inguinals
The pathway through which the testes descends in the male
Inguinal canal
What does the inguinal canal contain in
- ) Males
- ) Females
- ) Spermatic cord
2. ) Round ligament of the uterus
The inguinal canal begins internally at the
Deep inguinal ring
An invagination of the transversalis fascia
Deep inguinal ring
The inguinal canal ends externally at the
-A gap in the external oblique aponeurosis
Superficial inguinal ring
Form the superior wall of the inguinal canal
-the lower fibers of the terminal oblique
Falx inguinalis
What makes up the following walls of the inguinal canal?
- ) Anterior
- ) Posterior
- ) Superior
- ) Inferior
- ) External oblique aponeurosis
- ) Transversalis fascia
- ) Arching fibers of falx inguinalis
- ) Inguinal ligament
What are the 6 contents making up the spermatic cord?
- ) Ductus deferens
- ) Testicular artery
- ) Pampiniform plexus (testicular vein)
- ) Genital branch of genitofemoral nerve
- ) Autonomic nerves
- ) Lymphatic vessels
Innervates cremaster and provides cutaneous snesation to the anterior scrotum (male) and mons pubis and labia majora (female)
Genital branch of genitofemoral nerve (L1 and L2)
The genital branch of the genitofemoral nerve (L1 and L2) innervates the
Anterior scrotum (male) and mons pubis and labia majora (female)
As the testis descends through the inguinal ring, it and the spermatic cord take on coverings that are continuous with elements of the
Anterior abdominal wall
As the testis passes through the deep inguinal ring, it is covered by the
-continuous with the transversalis fascia
Internal spermatic fascia
As the testis passes through the intermediate inguinal ring, under the falx inguinalis, it is covered by some of the lower muscle fibers of the internal oblique muscle, which are called the
Cremaster muscle
The fibers covering the cremaster muscle are called the
Cremasteric Fascia
As the testis passes through the superficial inguinal ring, it is covered by an invagination of the external oblique fascia called the
External spermatic fascia
What does contraction of the cremaster muscle do?
Elevates the spermatic cord and testis
Serves a thermoregulatory function since the testes is warmer closer to the body and cooler when it is lower in the scrotum
Cremaster muscle
The cremaster will contract reflexly in response to stimulation of the skin of the lower abdominal wall or inner thigh this is called the
Cremateric reflex
The cremasteric reflex can be used to test the integrity of the
L1 spinal cord segment
In the female, the round ligament of the uterus occupies the inguinal canal and, after passing through the superficial inguinal ring, it descends to the
Labia Majus
The round ligament of the uterus ends in the
Superficial fascia
The round ligament of the uterus is derived from the
Caudal genital ligament
The round ligament of the uterus is homologous to the
Gubernaculum testis in the male
The coverings of the round ligament of the uterus are identical to the coverings of the
Spermatic cord
The gubernaculum attaches to the
Scrotum
The round ligament of the uterus attaches to the
Labia Majora
The thin scrotal skin, the absence of fat in the superficial fascia of the scrotum and the abundance
of sweat glands in the scrotal skin all facilitate
Heat Loss
What are three anatomic mechanisms that allow for regulation of testicular temperature?
- ) Cremaster muscle
- ) Dartos muscle
- ) Pampiniform plexus
A skeletal muscle in the covering of the spermatic cord that is innervated by the genital branch of the genitofemoral nerve
-causes elevation of the testis upon contraction
Cremaster muscle
A smooth muscle in the skin of the scrotum that is sympathetically innervated
Dartos muscle
What does the dartos muscle do?
Reduces the size of the scrotal sac and thereby decreases surface area to reduce heat loss
The dartos contracts to reduce heat loss in a
Cold environment
A venous plexus that is the continuation of the testicular vein
Pampiniform plexus
Forms an elaborate network of veins that surrounds the testicular artery in the spermatic cord
Pampiniform plexus
The large amount of surface area of contact between the testicular artery and the pampiniform plexus allows for the transfer of heat from the arterial blood in the testicular artery to venous blood in the testicular vein this is called
Thermal counter-current
Allows for the reduction of temperature of testicular artery blood before it reaches the testis, thus reducing the heat increase in the testis and lowering the thermal gradient between the testis and the environment
The thermal counter-current provided by the pampiniform plexus
What are the two types of inguinal hernias?
Direct and indirect
Follow the course of the descending testis through the inguinal canal
Indirect inguinal hernias
Enter at the deep inguinal ring and exit at the superficial inguinal ring
Indirect inguinal hernias
These hernias are covered by all of the same fascial layers as is the spermatic cord and testis since they follow the identical course as the descending testis
Indirect inguinal hernias
Do not follow the pre-formed path of the inguinal canal, rather they create their own path by tearing through the abdominal wall
Direct inguinal hernias
Direct inguinal hernias typically occur where the abdominal wall is weakest, which is at the
Superficial inguinal ring
The region through which direct inguinal hernias occur is called the
Inguinal (Hesselbach’s) Triangle
What are the following borders of the Inguinal (Hesselbach’s) Triangle?
- ) Lateral border
- ) Inferior border
- ) Medial border
- ) Inferior epigastric artery
- ) Inguinal ligament
- ) Lateral border of rectus abdominus
Typically, direct inguinal hernias are covered by the
External spermatic fascia
Prior to the descent of the testis, the parietal peritoneum forms a finger-like evagination called the
-descends through the inguinal canal
Processus vaginalis
The proximal portion of the processus vaginalis fuses, becomes fibrous and disappears after the
Descent of the testis
The distal portion of the processus vaginalis is within the
-remains unfused following descent of the testis
Scrotum (covers most of the testes)
The distal unfused portion of the peritoneum is the
Tunica vaginalis
A double layer of peritoneum with a small cavity containing fluid
Tunica vaginalis
The layer of the tunica vaginalis that is in direct contact with the testis is called the
Visceral layer
The outer layer of the utnica vaginalis is called the
Parietal layer
The tunica vaginalis covers the anterior, lateral and medial surfaces of the testis, but not the posterior surface, which is the location of the
Epididymis
When the proximal portion of the processus vaginalis does not fuse we have a
Patent processus vaginalis
A patent processus vaginalis results in a continuous opening from the peritoneal cavity of the abdomen into the scrotum. This will predispose for a
Congenital or acquired indirect inguinal hernia
If there is incomplete fusion of the processus vaginalis, leaving a small unfused portion, this results in a
Hydrocele of the spermatic cord
Distinguished from inguinal hernias because they pass deep to the inguinal ligament
Femoral hernias
Pass superficial to the inguinal ligament after emerging from the superficial inguinal ring
Inguinal hernias
Pass through the femoral ring to enter the femoral sheath
Femoral hernias
What are the following borders of the femoral ring?
- ) Anterior
- ) Medial
- ) Posterior
- ) Lateral
- ) Inguinal ligament
- ) Lacunar ligament
- ) Pectin pubis
- ) Femoral vein
The medial reflected portion of the inguinal ligament
Lacunar ligament
Typically, femoral hernias leave the femoral sheath through the
Saphenous hiatus
Make up about 75% of abdominal hernias and occur more commonly in men than in women (10:1)
Inguinal hernias (most are indirect)
Make up about 7% of abdominal hernias and occur more commonly in women than in men (4:1)
Femoral hernias
Femoral hernias and inguinal hernias have approximately the same frequency in
Women
If a hernia can be pushed back into the abdomen, it is called a
Reducible hernia
If a hernia can not be pushed back into the abdomen, it is called an
Incarcerated hernia
If the blood supply to the herniated organ is compromised, it is a
-will lead to tissue necrosis
Strangulated hernia
Have a particularly high risk (20% - 30%) of incarceration and strangulation
Femoral hernias
An outpouching of the skin and superficial fascia of the abdominal wall
Scrotum
The superficial fascia of the scrotum, the dartos fascia is continuous with
- ) Scarpa’s fascia in abdominal wall
2. ) Colle’s fascia in perineum
Is there fat in the superficial fascia of the scrotum?
No
Is there muscle in the superficial fascia of the scrotum?
Yes; dartos muscle (smooth muscle)
In the male, the spermatic cord (including the ductus
deferens, testicular vasculature, lymphatics and nerves) passes through the
Inguinal canal
The testis is attached to the scrotal wall by the
Gubernaculum