Flashcards in Anatomy of the Abdominal Wall, Inguinal Region and Hernias Deck (61)
Describe the difference in the innervation of the visceral and parietal peritoneum.
The parietal peritoneum has the same segmental somatic sensory innervation as the abdominal wall.
The visceral peritoneum has NO somatic sensory innervation
Which three nerves supply the antero-lateral abdominal wall?
Subcostal nerve (T12), Ilioinguinal nerve (L1), Iliohypochondriac nerve (L1)
Which nerves provide the motor supply for quadratus lumborum, psoas major and iliacus?
Quadratus Lumborum - T12-L4
Psoas Major - L2-L4
Iliacus - L2-L4
Where is the lumbar plexus located?
Which line defines a border between the lymphatic drainage to different groups of lymph nodes?
Where do the superficial lymphatics above and below the transumbilical line drain to?
Above - pectoral group of axillary lymph nodes
Below - superficial inguinal lymph nodes
Where do the deep lymphatics above and below the transumbilical line drain to?
Above - mediastinal lymph nodes
Below - external iliac and para-aortic lymph nodes
Where does the inguinal ligament attach to the pelvis?
Anterior superior iliac spine and the pubic tubercle
Why is the inguinal region clinically important?
It is an area of inherent weakness where most abdominal hernias occur.
What defines the ends of the inguinal canal?
The superficial and deep inguinal rings
How long is a normal inguinal canal?
Are hernias more common in males or females?
More common in males
What are the contents of the inguinal canal in males and females?
Males - spermatic cord + ilioinguinal nerve
Females - round ligament of the uterus + ilioinguinal nerve
At what stage in intrauterine life do the testes usually enter the inguinal canal and drop into the scrotum?
Testicular descent starts at 7 weeks IUL. They enter the inguinal canal around 28 weeks IUL and enter the scrotum around 32-36 weeks IUL
What passes through the femoral canal?
Efferent lymphatics and a lymph node
NOTE: the femoral artery and vein do NOT go through the femoral canal (the femoral vein, in fact, is the lateral wall of the femoral canal)
Protrusion of part or a whole of an organ or tissue through the walls of the structure that contain it.
What are the three main parts of a hernia?
Weakness/hole, hernial sac, contents of the hernial sac
What are some clinical symptoms and signs of a hernia? What symptoms indicate that the hernia should be treated as an emergency situation?
Swelling or protrusion in the groin area
Pain/lack of pain and discomfort
May be intermittent or presenting all the time
May be reducible or irreducible
Strangulation may occur leading to tissue death causing symptoms such as vomiting, constipation and intestinal obstruction - this is considered an emergency
What factors increase the risk of femoral hernia in women?
Age and number of pregnancies
Where are the superficial and deep inguinal rings positioned?
Superficial inguinal ring is located immediately above and medial to the pubic tubercle
Deep inguinal ring is 1.5 cm above the midpoint of the inguinal ligament
The superficial and deep inguinal rings are holes in which muscles/fascia?
Superficial inguinal ring is a hole in the external oblique
Deep inguinal ring is a hole in the transversalis fascia
What is the conjoint tendon?
The lowest fibres of the internal oblique and the transversus abdominis come together to form the conjoint tendon, which attaches medially to the pubic crest .
What makes up the four walls of the inguinal canal?
Anterior - external oblique (the whole way) + internal oblique (lateral 1/3)
Posterior - transversalis fascia + conjoint tendon medially
Superior - arching over fibres of the internal oblique and transversus abdominis and the conjoint tendon medially
Inferior - inguinal ligament (folding inwards of the lower border of the external oblique aponeurosis)
What region do direct inguinal hernias occur through and where is this region positioned?
Hesselbach's Triangle - medial to the inferior epigastric vessels
Where is the defect in indirect inguinal hernias positioned?
Dilation of the deep inguinal ring - lateral to the inferior epigastric vessels
What type of patients tend to have direct inguinal hernias and what behaviours and defects are direct inguinal hernias associated with?
Older patients - it is associated with chronic straining and weak musculature
It is caused by a defect in the posterior abdominal wall.
What type of patients tend to have indirect inguinal hernias?
Young adults and children
What type of patients are more likely to get femoral hernias?
Women and the elderly
What makes up the walls of the femoral canal?
Where is an inguinal hernia usually seen on the surface
Superior - inguinal ligament
Inferior - pectineus fascia
Medial - lacunar ligament
Lateral - femoral vein