Abdomen & pelvis Flashcards
At what level does the subcostal plane lie?
L3
At what levels does the intubercular plane lie?
L4/5
At what level is the transpyloric plane?
L1
Surface markings of the kidney
Extend between vertebrae T12 – L3, left kidney slightly higher than right, renal hila at vertebral level L1
Where does the renal arteries arise?
Abdominal aorta, inferior to the origin of the SMA between L1 & L2
Which spinal nerves supply the muscles of the abdominal wall?
T7 - L1
Attachments of the external oblique muscles
Lower 8 ribs, lateral lip of the iliac crest
Extent of the external oblique aponeurosis
Xiphoid to pubic symphysis
What is the linea alba
Midline abdominal structure formed by the aponeurosis of the external oblique
Inguinal ligament attachments
Inferior edge of the external oblique from ASIS to public tubercle
The superficial inguinal ring is an opening in what?
location
External oblique aponeurosis
superior to the pubic tubercle
Attachments of the internal oblique muscle?
Thoracocolumbar fasica,iliac crest, lateral 2/3 of inguinal ligament, lower 3-4 ribs and costal cartilage and pubic crest
Aponeurosis to linea alba
Attachments of the transversus abdominis
Thoracoclumbar fascia, ilac crest, lateral 1/3 of inguinal ligement, lower 6 ribs + CC, pubic crest
Aponeurosis to linea alba
What forms the conjoint tendon?
Aponeurosis of internal oblique and transversus abdominis
Rectus abdominis attachements
CC of ribs 5-7, xiphoid, pubic symphysis and cresr
What is the rectus sheath derived from?
Aponeurosis of external, internal oblique and transversus abdominis
What does the rectus sheath surround?
Each rectus abdominis
+
pyramidalis muscle
Superior and inferior
epigastric vessels
Terrmination of IC nerves T7-T11
12th thoracic nerve and accompanying vessels
Position of the inguinal canal
4cm canal between the deep and superficial inguinal rings, just above and parallel to the medial half of the inguinal ligament
Anterior wall of the inguinal ligament
Posterior wall
External oblique aponeurosis
Transversalsis fascia
Roof of the inguinal ligament
Floor
Transversus abdominis and internal oblique
Medial 1/2 of inguinal ligament
What is the deep inguinal ring a opening in?
+ location
Trasversalis fascia just superior to the mid inguinal point
Contents of the inguinal canal?
Genital branch of the genitofemoral nerve
Spermatic cord in men
Round ligament in women
Ilioinguinal nerve
Mid inguinal points vs mid point of inguinal ligament
Mid-inguinal point – halfway between the pubic symphysis and the anterior superior iliac spine. The femoral pulse can be palpated here.
Midpoint of the inguinal ligament – halfway between the pubic tubercle and the anterior superior iliac spine (the two attachments of the inguinal ligament). The opening to the inguinal canal is located just above this point.
Quadratus lumborum
Function
Extent
Innervation
Depresses and stabilises the 12th rib, contributes to lateral bending of the trunk
Fills space between the 12th rib and iliac crest on both sides of the vertebral column
Anterior rami of T12, L1-4
Which muscle overlaps the quadratus lumborum medially?
Which muscle lies immediately laterally to it?
Psoas major
Transversus abdominis
Extent of psoas major
Innervation
Actions
T12, L1-5 VB -> into the lesser trochanter of the femur
Flexion of the thigh at hip, flexes the trunk against gravity when the body is supine
Anterior rami L1-3
Iliacus
Extent
Action
Innervation
Fills the iliac fossa -> passes inferiorly to join with psoas to attach distally to the lesser trochanter of the femur
Flexes thigh at hip joint when trunk is stabilised, flexes trunk against gravity when body is supine
Femoral nerve (L2 – L4)
Inguinal hernias appear where?
Above and medial to the pubic tubercle
Femoral hernias appear where?
Through the femoral canal, below and lateral to the pubic tubercle
Direct inguinal hernias where in relation to the epigastric vessels?
Indirect?
Medial
Lateral
What do direct inguinal hernias push against?
Weakened conjoint tendon
Femoral sheath is an extension of>
Abdominal transversalis fascia
Where do the lymph from the testis drain to?
Where does the scrotum lymph drain to?
Paraortic nodes
superficial inguinal nodes.
Where do the testes and epididymis receive innervation from?
Testicular plexus – a network of nerves derived from the renal and aortic plexi. They receive autonomic and sensory fibres.
Where does the:
L testicular vein
R. testicular vein
drain into?
L. renal vein
IVC
Why do testis refer pain to the umbilical region?
Nerves derived from T10 /11
What kind of nerve supply does the parietal peritoneum have?
It receives the same somatic nerve supply as the region of the abdominal wall that it lines; therefore, pain from the parietal peritoneum is well localised.
What kind of nerve supply does the visceral peritoneum have?
The visceral peritoneum has the same autonomic nerve supply as the viscera it covers. Unlike the parietal peritoneum, pain from the visceral peritoneum is poorly localised and the visceral peritoneum is only sensitive to stretch and chemical irritation.
Intraperitoneal organs include: (8)
stomach, spleen, liver, first and fourth parts of the duodenum, jejunum, ileum, transverse, and sigmoid colon.
Define retroperitoneal organs?
Retroperitoneal organs are not associated with visceral peritoneum; they are only covered in parietal peritoneum, and that peritoneum only covers their anterior surface.
Define primarily retroperitoneal organs?
Primarily retroperitoneal organs developed and remain outside of the parietal peritoneum. The oesophagus, rectum and kidneys are all primarily retroperitoneal.
Define secondarily retroperitoneal organs?
Secondarily retroperitoneal organs were initially intraperitoneal, suspended by mesentery. Through the course of embryogenesis, they became retroperitoneal as their mesentery fused with the posterior abdominal wall. Thus, in adults, only their anterior surface is covered with peritoneum. Examples of secondarily retroperitoneal organs include the ascending and descending colon.
Which abdominal organs are retroperitoneal?
SAD PUCKER
S = Suprarenal (adrenal) Glands
A = Aorta/IVC
D =Duodenum (except the proximal 2cm, the duodenal cap)
P = Pancreas (except the tail)
U = Ureters
C = Colon (ascending and descending parts)
K = Kidneys
E = (O)esophagus
R = Rectum
Define mesentery
A mesentery is double layer of visceral peritoneum. It connects an intraperitoneal organ to (usually) the posterior abdominal wall.
Define peritoneal ligaments
A peritoneal ligament is a double fold of peritoneum that connects viscera together or connects viscera to the abdominal wall.
Define foregut contents:
Foregut – oesophagus, stomach, pancreas, liver, gallbladder and the duodenum (proximal to the entrance of the common bile duct).
Define midgut contents:
Midgut – duodenum (distal to the entrance of the common bile duct) to the junction of the proximal two thirds of the transverse colon with the distal third.
Define hindgut contents:
Hindgut – distal one third of the transverse colon to the upper part of the anal canal.
What divides the supra and infra colic compartments?
transverse mesocolon
Supracolic compartment contains?
Supracolic compartment – lies above the transverse mesocolon and contains the stomach, liver and spleen.
Infracolic compartment contains?
Lies below the transverse mesocolon and contains the small intestine, ascending and descending colon.
What divides the infracolic compartment into left and right infracolic spaces?
mesentery of the small intestine.
What connects the supra and infracolic compartments?
Paracolic gutters
What is ‘the mesentery’ ?
Double fold of peritoneal tissue that suspends the small intestine and large intestine from the posterior abdominal wall.
3 functions of the mesentery
Suspends the small and large intestine from the posterior abdominal wall; anchoring them in place, whilst still allowing some movement.
Provides a conduit for blood vessels, nerves and lymphatic vessels.
Postulated to play a pathological role in inflammatory diseases such as Crohn’s disease.
Root of the mesentery
left side of the L2 vertebra to the right sacroiliac junction roughly.
Extension of the greater omentum:
Descends from greater curvature of stomach and first part of duodenum, drapes inferiorly over transverse colon, jejunum and ileum, folds back up and ascends to adhere to transverse colon/mesocolon before arriving at posterior abdominal wall
Root of sigmoid mesentery?
Near division of left common iliac artery, l
At what level is the gastro-oeophageal junction?
T11 vertebra,
Dual blood supply of the liver
Hepatic artery proper (coelic trunk)
Hepatic protal vein
Contents of porta hepatis
Hepatic portal vein
Hepatic artery proper
Common bile duct
What carries sympathetic stimulation to the gall bladder?
Coeliac plexus
What carries parasympathetic stimulation to the gall bladder?
Vagus nerve
Iliohypogastric Nerve
Roots
Motor fx
Sensory fx
L1 (T12)
Internal oblique and transversus abdominis
Posterolateral gluteal skin in the pubic region.
Ilioinguinal Nerve
Roots
Motor fx
Sensory fx
L1
Innervates the internal oblique and transversus abdominis.
Skin on the superior antero-medial thigh + ant. genitalia
Genitofemoral Nerve
Roots
Motor fx
Sensory fx
L1, L2
The genital branch innervates the cremasteric muscle.
Genital - ant. genitalia
Femoral - upper ant. thigh
Most common position of the (vermiform) appendix?
Retrocaecal
Which bits of the small intestine are intra peritoneal ?
Small part of 1st and all of 4th part
Arterial supply of upper duodenum
Superior pancreaticduodenal arteries (from gastroduodenal branch of hepatic artery proper)
Arterial supply of lower duodenum
Inferior pancreatic duodenal arteries (from SMA)
Arterial supply to the stomach comes from?
Coeliac trunk branches
Where is pain referred from the small bowel to?
T10, periumbilical
Where does blood supply of bowel switch from SMA to IMA?
2/3 along transverse colon
Referred pain of foregut to which spinal level?
T7-9
Referred pain of mid gut to which spinal level?
T10
Referred pain of hindgut to which spinal level?
T12
Sites of portosystemic anastmosis?
Lower 1/3 oseophagus
Half way down the anal canal
Para umbilical veins
At the veins of retroperitoneal structures
Which ribs does the spleen lie between?
9-11
What vertebral levels do the kidneys extend between?
T12 - L3
Renal arteries branch at which level?
L2
Nerve supply to the bladder derived from which spinal levels?
S2/3/4
What does the ovary hang off?
Broad ligament
What key structure lies posterior to the ovary?
Ureter
What nerve lies laterally to the ovary?
Obturator nerve
Sections of the uterine tube
Lateral to Medial
Ostium -> Infundibulum -> Ampulla -> Isthmus
Ovary referred pain to?
T10 - umbilical
Uterine body referred pain to?
T12/L1, suprapubic
Arterial supply to the rectum
Superior
Middle
Inferior
IMA
Internal iliac
Internal pudendal
