GI - Class 1 Flashcards
What are the two imaginary lines used to divide the abdomen in 4 quadrants?
Transumbilical plane
Median plane
What are the imaginary lines used to divide the abdomen into 9 regions?
Two horizontal:
subcostal plane and trans tubercular plane
Two vertical:
right and left midclavicular planes
Name a few organs in the right hypochondriac
Liver, gallbladder, right kidney
Name a few organs in the epigastric
stomach, pancreas, duodenum
Name a few organs in the left hypochondriac
spleen, left kidney, pancreas
Name a few organs in the right lumbar
liver, ascending colon, gallbladder
Name a few organs in the umbilical
umbilicus, small intestine, duodenum
Name a few organs in the left lumbar
descending colon, left kidney
Name a few organs in the right iliac
appendix, caecum
Name a few organs in the hypogastric region
urinary bladder, sigmoid colon, female reproductive organs
Name a few organs in the left iliac
descending colon, sigmoid colon
What are the five bilaterally paired muscles in the anterolateral abdominal wall?
3 flat muscles: external oblique, internal oblique and transversus abdominis
2 vertical muscles: rectus abdominis and pyramidalis
What is the action and innervation of the external oblique muscle?
compresses and supports abdominal viscera, flex and rotate trunk.
innervate by thoraco-abdominal nerves (anterior rami of T7-T11)
subcostal nerve
What is the action and innervation of the internal oblique muscle?
compresses and supports abdominal viscera, flex and rotate trunk.
innervate by thoraco-abdominal nerves (anterior rami of T7-T11)
subcostal nerve
first lumbar nerve
What is the action and innervation of the transversus abdominis muscle?
compresses and supports abdominal viscera.
innervate by thoraco-abdominal nerves (anterior rami of T7-T11)
subcostal nerve
first lumbar nerve
What is the action and innervation of the rectus abdominis muscle?
flexes trunk (lumbar vertebrae) compresses abdominal viscera, stabilises and controls tilt of pelvis(antilordosis) innervate by thoraco-abdominal nerves (anterior rami of T7-T11) subcostal nerve
What is the rectus sheath?
formed by the interlaced aponeurosis of the flat abdominal muscles enclosed in the rectus abdominis and the pyramidalis.
What is the arcuate line?
demarcates the transition between the posterior rectus sheath covering the superior three quarters of the rectus abdominis proximally and the transversalis fascia covering the inferior quarter.
What vertebral level is the umbilicus
L3-L4
What dermatome supplies the level of the umbilicus
T10
The inguinal ligament is attached to which two bony points of the hip bone
pubic tubercle and the anterior superior iliac spine
4 distinct functional layers of the gastrointestinal tract?
mucosa, submucosa, musculares propria and the serosa/ adventitia
What are the three layers of the mucosa?
epithelium, lamina propria and muscularis propria
What are the four basic mucosal types found in the GI tract?
- Protective
- secretory
- absorptive
- absorptive/ protective
Describe the protective mucous membrane
stratified squamous epithelium found in the oral cavity, pharynx, oesophagus and anal canal
Describe the secretory mucous membrane
closely packed straight glands with goblet cells found only in the stomach
Describe the absorptive mucous membrane
vili with short glands typical of the entire small intestine
Describe the absorptive/ protective mucous membrane
simple columnar epithelium with tubular glands - lines the whole of the large intestine
What is the innervation of the abdominal muscles?
Ventral rami of T7-L1
thoraco-abdominal nerves
Formation of inguinal canal
An evagination of peritoneum
called processus vaginalis
develops along the path of
gubernaculum
Define gubernaculum
A fibrous
cord or tissue
pulls the testis / ovary
down
What is Cryptorchidism
Undescended testes
What is the prevalence of cryptorchidism?
Occurs in 30% of premature males. Can be unilateral or bilateral
What is the cause of cryptorchidism?
Deficiency of androgen production by the fetal testis
What condition does cryptorchidism predispose.
Testicular cancer
What are the contents of the inguinal canal?
spermatic cord in males and round ligament of the uterus in females. Also contains blood, lymphatic vessels and ilioinguinal nerve in both the sexes
Anatomical location of the inguinal canal
Lies parallel and superior to the medial half of the inguinal ligament
Features of the deep inguinal ring
Entrance to the inguinal canal. Part of transversalis fascia
Location – superior to the middle of inguinal ligament, lateral to inferior epigastric artery
Features of the superficial inguinal ring
Exit of the canal. Present in the external oblique aponeurosis
Location – Above and lateral to pubic tubercle
Anterior wall of inguinal canal
External oblique aponeurosis
Posterior wall of the inguinal canal
Trasversalis fascia & medial part by conjoint tendon (internal oblique + transversus abdominis)
Roof of the inguinal canal
Laterally by transversalis fascia and centrally by internal oblique and transversus `abdominis muscles
Floor of the inguinal canal
inguinal ligament
What is a hernia?
A hernia is an abnormal protrusion of a viscus (organ) or part of a viscus through an opening in the cavity in which it is normally contained. About 75% of all herniae occur at the groin.
What are the different types of hernia
Inguinal hernia – direct and indirect Femoral hernia Umbilical hernia Paraumbilical hernia Epigastric hernia Incisional hernia Hiatus hernia
Indirect inguinal hernia
Indirect inguinal hernia is common in young individuals – congenital weakness
Direct inguinal hernia
Direct inguinal hernia is more common in old people – Lax muscles
