Download anterior abdominal wall

ANTERIOR ABDOMINAL WALL
Abdominal region
UR
UL
LR
LL
Layman term
RH
EG
LH
Transpyloric/L1
RL
UR
LL
Subcostal/L3
RI
HYPG
LI
Intertrochentrum/L5
L/midclavi.
R/midclavi.
Anterior abdominal wall have 6 layers
1) Skin
2) Superficial fascia
3) Deep fascia
4) Muscles
5) Extraperitoneal layer
6) Parietal peritoneum
SKIN
 Loosely attached to underlying structure except umbilicus
 Line of cleavage (any incision need to follow this line to minimize the scar formation in
abdomen
 Usually for emergency cases, the incision is done in vertical line opposed the usual
cleavage line; horizontally
 Umbilicus =scar that represent the site of attachment of umbilical cord in the fetus
 Blood supply
a) Arteries
 Midline-branches of sup/inf. epigastric arteries
 Flanks-branches of IC/lumbar/deep circumflex iliac arteries
 Inguinal-branches of femoral artery (superficial epigastric /circumflex iliac/external
pudendal arteries)
b) Vein
 Above-lateral thoracic to axillary
 Below-superficial epigastric/great saphenous to femoral vein
c) Nerve
 Ant. Rami of lower 6 thoracic (lower 5 intercostal/subcostal) & 1st lumbar nerve
(iliohypogastric/ilioinguinal nerves)
 Dermatomes
1) T7-epigastrium over xiphoid process
2) T10-umbilicus
3) L1-above inguinal ligt./symphysis pubis
MBBS anatomy/iium syerah’s notes
SUPERFICIAL FASCIA
 Divide into 2:
1) Superficial fatty layer=Camper fascia
 continuous with other fat over the body
 may too thick up to 10 cm
2) deep membranous layer =Scarpa fascia
 thin & fade out laterally
 inferior- get continue with deep fascia one finger above the inguinal ligt.
 Midline inferiorly-tubular sheath for penis/clitoris
 Below perineum-enter wall of scrotum/labia majora
 Colles’fascia-margin of pubic arch
 Posterior-fuses w perineal body/post margin of perneal membrane
 Dartos Muscle(thun layer of smooth muscle)-fatty layer of superficial fascia
DEEP FASCIA
 Thin layer of connective tissues
 Cover muscle
 Lies deep to membranous layer of superficial fascia
FUNCTION OF ANTERIOR ABDOMINAL WALL
 Oblique muscle flex & rotate the trunk
 RA=flex trunk, stabilize pelvis
 Pyrimidalis=keep linea alba taut during the process
 Muscles of ant/lat abd wall help diaphragm during inspiration by relax diaphragm
descend allowing the accomadation of viscera
 Help in forced expiration during cough & sneeze by pulling down the sternum & ribs
 Increase intra-abd pressure to help in maturation, defecation. Vomiting, & parturition
FASCIA TRANSVERSALIS
 Lines transverse abdominus
 Continuous with similar layer lining the diaphragm & iliacus muscle
 Femoral sheath=fascia transversalis + fascia iliaca
EXTRAPERITONEAL FAT
 Thin layer of connective tissue
 Variable amount of fat
 Lies between fascia transversalis and parietal peritoneum
PARIETAL PERITONEUM
 Thin serous membrane
 Continuous below parietal peritoneum lining pelvis
MBBS anatomy/iium syerah’s notes
INGUINAL LIGAMENT
 Strong ligament that connect the right/left ASIS with pubic tubercle
 Formed by lower border of aponeurosis of external oblique muscle
INGUINAL CANAL
 4 cm length
 Passage where the gonads passed
 In embryo state, the ovary was in abdominal region but then it is descend upon growth
 The male gonad; testes should be outside the body to allow the optimum temperature of
spermatogenesis 37 C
 Male-the oblique passage pass to & from testes (spermatid cord &
iliohypogastric/ilioinguinal nerve)
 Female-allow round ligt. Of uterus to pass from uterus to labia majora & ilioinguinal
nerve
 2 opening
1) Deep inguinal ring & oval opening fascia transversalis
2) Superficial inguinal ring-defect of ext. OM
 Wall of canal
1) Ant- EXT OM
2) Post-fascia transversalis & medial conjugated tendons
3) Roof-INT OM & transverses abdominus muscles
4) Floor-inguinal ligt. & lacuna ligt.
MBBS anatomy/iium syerah’s notes
POSTERIOR ABDOMINAL WALL
Formed by:
1)
2)
3)
4)
5)
6)
7)
5 lumbar vertebral / intervertebral disc
12 th ribs
Upper of bony pelvis -Iliacus
Psoas muscle
Quadrates lamborum
Apo of origin of transverses abdominus muscle
Fascia lining the abdominal wall
MUSCLES
PSOAS MUSCLE
 Fibers run downwards
& laterally
 Leave abdomen &
enter thigh by passing
behind inguinal ligt.
 Enclosed by fibrous
sheath from lumbar
fascia-thickened to
form MEDIAL ARCUATE
LIGT.
 Fx-flex thigh at hip joint
like action sitting up
from lying.
ORIGIN
 transverse process
 vertebral bodies
 intervertebral disc from
12th thoracic to 5th
lumbar
lesser trochanter of
INSERTION femur
FACTS
NERVE
SUPPLY
lumbar plexus
QUADRATUS
LAMBORUM
 Flat, quadrilateral
muscle along the
vertebral column
 Fibers run upward &
medially
 Ant. Surface by lumbar
fascia-thickened to
form LATERAL
ARCUATE LIGT (above)
7 iliolumbar ligt (
below)
ILIACUS
 Fan shaped
 Combined muscle
refer as iliopsoas
 iliolumbar ligt.
 iliac crest
 tip of transverse
process of lower
lumbar
12th ribs & transverse
process of upper 4
lumbar vertebra
 iliac fossa
lesser trochanter of
femur with psoas
muscle
lumbar plexus
Femoral plexus
RETROPERITONEAL SPACE
 Lies on posterior abd wall behind the parietal peritoneum.
 Formed from 12th thoracic to 12th ribs and iliac crest
 Posterior/floor- form from medial to lateral by psoas and quadrates lamborum and
transverse abd muscles
 ALL the muscle covered with fascia
 In front of fascia- fatty connective tissue forming a bed for suprarenal gland, kidney,
ascending and descending colon & duodenum
 Also contain ureters, renal and gonadal blood vessels
MBBS anatomy/iium syerah’s notes