Recap lecture 10 abdomen Flashcards
What are the 4 main parts of the abdomen?
1) Abdominal wall
2) Abdominal cavity
3) Peritoneal cavity
4) Viscera
What innervates the viscera pre-splenic flexure?
Vagus nerve
What does the pelvic brim separate?
Greater pelvis of abdominal cavity and lesser pelvis of pelvic cavity
What is the superior part of the ilium bones called?
Iliac crest
1) What is the most medial anterior part of the pelvis called?
2) What is superior and slightly lateral to this?
1) Symphysis
2) Pubic tubercle
What is the importance of the linea alba?
If you cut vertically down it you won’t cut through muscle.
(goes from xyphoid process, through umbilicus, to pubic symphysis)
What are the layers of the anterolateral abdominal wall? (from superficial to deep)
1) Skin
2) Superficial fascia (SQ)
3) Investing (deep) fascia
4) Endo-abdominal fascia
5) Extraperitoneal fat
6) Parietal peritoneum
What covers external aspects of 3 muscle layers of abdominal wall and their aponeurosis?
Investing (deep) fascia
What are the two layers of the superficial fascia of the anterolateral abdominal wall? Describe each
1) Camper fascia: fatty layer
2) Scarpa fascia: deep membranous layer
Where is the superficial fascia of the abdomen found? How many layers does it have?
Inferior to umbilicus; 2 layers
What does the parietal peritoneum line?
Abdominal cavity
Where in the abdomen is there a potential space for fluid/infection to spread?
Between scarpa fascia and deep fascia covering abdominal muscles
What does the Scarpa fascia attach and fuse to?
Attaches to pubic bone and fuses with deep fascia of thigh
List the 5 paired muscles of the abdominal wall
-3 flat muscles: External oblique, internal oblique, transversus abdominis mm.
-2 vertical muscles: Rectus abdominis, pyramidalis mm.
What forms the aponeurosis anterior?
Flat muscle
1) What encloses the rectus abdominis?
2) What does enclosing structure then form at the midline?
1) Rectus sheath
2) Linea alba
Where does the linea alba run from and to?
Xyphoid to pubic symphysis
What are the anterolateral abdominal muscles? (6)
1) Obliques: EO, IO, TA
2) Rectus: rectus sheath, linea alba
3) Pyramidalis
1) What encloses the pyramidalis muscle? Where is it?
2) What does it arise from and insert into?
3) When does it tense?
1) Rectus sheath; pyramidalis is anterior to inferior part of rectus m.
2) Arises from pubic crest, inserts into linea alba
3) During Valsalva maneuver
What is the aponeurosis of flat abdominal muscles?
Rectus sheath
What are the 3 sections of the rectus sheath?
1) Superior to arcuate line
2) Arcuate line
3) Inferior to arcuate line
Superior to the arcuate line:
1) What makes up the anterior rectus?
2) What makes up the posterior rectus?
1) Anterior: EO fascia + anterior lamina of IO
2) Posterior: Posterior lamina of IO + TA fascia
(eo is external oblique, io is internal oblique, TA is transversus abdominis
1) Where is the arcuate line?
2) What does it demarcate?
1) 1/3 distance from umbilicus to pubic symphysis
2) The transition between the posterior rectus sheath covering the superior ¾ of the rectus abdominis proximally, and the transversalis fascia covering the inferior ¼
At the arcuate line, what pierce the posterior rectus sheath to provide blood to rectus muscle?
Inferior epigastric arteries and veins
1) What 2 muscles are contained within the rectus sheath?
2) What vessels are enclosed within it?
3) What nerves are enclosed within it?
1) Rectus abdominis m. and pyramidalis m.
2) Anastomosing inferior and superior epigastric vessels, lymphatics
3) Thoraco-abdominal and subcostal nerves (anterior rami of distal T7-12 spinal nerves)
What are the 5 peritoneal folds that pass toward the umbilicus?
1) Median umbilical fold (ligament) (remnant of urachus, which is the apex of fetal bladder to umbilicus)
2&3) R & L medial umbilical fold (ligament) (umbilical arteries remnant)
4&5) R & L lateral umbilical fold over Inferior Epigastric a
What is the urachus? What is a remnant of it?
The apex of fetal bladder to umbilicus; median umbilical fold (ligament)
What is the remnant of the umbilical arteries?
Right and left medial umbilical folds (ligaments)
The right and left lateral umbilical folds are over what?
Inferior epigastric arteries
1) Where are indirect inguinal hernias found?
2) Where are direct inguinal hernias (straight through inguinal triangle) found?
1) Lateral inguinal fossa
2) Medial inguinal fossa
There’s a small amt of peritoneal fluid in abdominal cavity; abnormal accumulation is called what?
Ascites
Visceral pain tends to be with _____________ of GI tract
distention
Describe the associated organs of the abdominal cavity
1) Liver: produces bile which helps digest fats
2) Pancreas: secretes pancreatic enzymes to help with digestion via exocrine process
3) Spleen: immune and hematological functions, can add RBCs
Superficial to the pelvic diaphragm and deep to the skin is the ________________.
perineum
List the 4 dermatomes of the abdomen. Where are they, and what does each innervate?
1) Thoracoabdominal: T7-11
-Lateral and anterior branches (of intercostal segmental nerves)
2) Subcostal: T12
-Lateral and anterior branches
3) Iliohypogastric: L1
-Skin over iliac crest, upper inguinal and hypogastric region
4) Ilioinguinal: L1
-Skin of scrotum or labia majorus, mons, adjacent medial aspect of thigh (afferent for cremaster reflex)
Infection below umbilicus will infect ___________ nodes first, chest infection will affect the ______________ lymph nodes
inguinal; axillary
What vein runs up the lateral side of the abdomen? What does it come from and turn into?
Thoraco-epigastric vein from superficial epigastric (from femoral) turns into lateral thoracic vein
1) Where does the inguinal ligament run from?
2) What forms the inguinal ligament?
1) ASIS to PUBIC tubercle
2) Inferior margin of EO
1) What does the inguinal canal do?
2) What is responsible for much of the structural features of the inguinal canal/ region
1) Allows structures to travel between abdominal cavity and scrotum
2) Descent of testis from abdomen into perineum during development; “vascular and nerve follow the bouncing ball”
What structures are inferior (not to be confused w deep) to the inguinal ligament? What can one of them cause?
1) Lateral cutaneous nerve of the thigh (compression can cause meralgia parasthetica)
2) Femoral canal with: femoral n., fem art, fem vein (VAN)
1) The internal surgical landmark corresponding to the inguinal ligament is the ____________________
2) What does the EO form?
3) Which is important to surface anatomy, inguinal ligament and iliopubic tract?
1) Iliopubic tract
2) Inguinal ligament
3) Inguinal ligament
VANs are __________to inguinal ligament, and inferior epigastric nerves are _____________ to deep ring
inferior; lateral
1) What makes up the inguinal triangle? (3 things)
2) A direct hernia pushed through triangle medially to what?
1) Rectus, inguinal ligament, inferior epigastric vessels
2) Inferior epigastric vessels
What is the clinical application of the fact that the ligament follows spermatic cord from internal ring?
Direct hernias don’t go all the way into scrotum usually, but indirect hernias that follow the spermatic cord can go into the testicles
What’s the difference between a direct and indirect hernia?
1) Direct hernia: hernia sac pushes MEDIAL to inferior epigastrics thru peritoneum, transversalis fascia and inguinal triangle, parallels spermatic cord, weakness in anterior abd wall, usually > 40 y/o
2) Indirect hernia: hernia sac inside spermatic cord, younger men, patency of processus vaginalis
Inferior epigastric vessels follow what?
Arcuate line
1) What is a hydrocele? What side is it more common on?
2) What is a varicocele? What side is a pampiniform plexus varicocele usually on?
1) Buildup of fluid in scrotum; equally common bilaterally
2) Varicose vein in scrotum; benign usually on left side because the right comes out of IVC at a different angle.
1) What is the cremaster muscle a continuation of?
2) What does its contraction do?
3) What innervates it?
4) What reflex is it involved in? Explain this reflex.
1) IO muscle
2) Raises the testicle
3) Genital branch of the genitofemoral nerve
4) Cremaster reflex: reflex is elicited (very active in kids) by stroking the inner thigh, afferent via ilio-inguinal n., efferent genitofemoral n.
What is the Dartos muscle and what does it do?
1) Smooth muscle in the wall of the scrotum (gentofemoral nerve innervates?)
2) Contraction of skin of scrotum; wrinkles
What muscles (2) and veins (1) help keep the testicle close to body in cold temps?
1) Cremaster muscle and dartos muscle
2) Pampiniform venous plexus
What do the parietal and visceral layers of the tunica vaginalis make up?
1) Parietal: Cavity of the tunica vaginalis
2) Visceral: Testis
What do the testicular arteries arise from?
Abdominal aorta (L2)
-What do the left and right testicular veins empty into?
-In which testicular vein are varicoceles more common? Where are they concerning?
1) Left testicular vein empties into left renal vein
-Varicocele more common
2) Right testicular vein empties into IVC
-Varicocele concerning for IVC mass; renal cell carcinoma
What are the endocrine and exocrine functions of the testes?
1) Endocrine function: Testosterone
2) Exocrine function: Sperm
Where is fluid located in the scrotum?
Tunica vaginalis
List the nerves of the scrotum and what each innervates
1) Genital br. of the genitofemoral n: to anterolateral surface
2) Ilioinguinal n: to anterior surface
3) Perineal br of Pudendal nerve: to posterior surface
4) Perineal br of posterior cutaneous nerve: of the thigh
1) Where does vascular supply and drainage of the scrotum come from?
2) Where do the scrotal lymphatics drain? How is this different from testicular lymphatics?
1) Pudendal vessels
2) To superficial inguinal nodes
-Testicular lymphatic drainage: goes to midline (pre-aortic) nodes
What provide the afferent and efferent parts of the Cremaster reflex?
1) Afferent: ilio-inguinal nerve
2) Efferent: genital br. of the genitofemoral nerve