Dissection Abd Wall
Dissection Abd Wall
Dissection Abd Wall
1. Linea alba
➢ Aponeurotic raphe
running from xiphoid
process to public
symphysis
2. Semilunar lines
3. External oblique muscle
4. Anterior lamina of the rectus
sheath
1. Linea alba
2. Semilunar lines
➢ One on each side of rectus
abdominis
➢ Mark the point where the
aponeurosis of internal
oblique splits to encase the
rectus sheath
3. External oblique muscle
4. Anterior lamina of the rectus
sheath
1. Linea alba
2. Semilunar lines
3. External oblique muscle
➢ Fibres travel inferiorly as
they pass anteromedially
➢ Immediately deep to
subcuteanous tissue
4. Anterior lamina of the rectus
sheath
1. Linea alba
2. Semilunar lines
3. External oblique muscle
4. Anterior lamina of the rectus
sheath
➢ Formed by the aponeuroses
of external and internal
oblique superior to arcuate
line
➢ Below arcuate line- formed
by the aponeuroses of
external and internal oblique
and transversus abdominis
Rectus sheath
Above
Arcuate line
Below
Arcuate Line
➢Seen in the Posterior Internal oblique
lamina of the rectus Transversus abdominis
Transversalis fascia
sheath
Transversalis fascia
External surface of ribs 5-12
External Oblique linea alba, pubic
tubercle, anterior iliac crest
FREE EDGE
Thoracolumbar
Internal Oblique fascia, anterior
2/3 iliac crest
linea alba,
inferior borders
of ribs 10-12,
pectin pubis
(pectineal line)
*Torsion of the
trunk
Internal surfaces of
Transversus abdominis the 7th -12th costal
cartilages,
thoracolumbar
fascia, iliac crest
Linea alba, pubic
crest, pectin pubis
Rectus abdominis Tendinous
intersection
Anterior
lamina of
rectus
sheath
Pyramidalis
Pubic crest Linea
alba
Ilioinguinal
nerve
Inguinal Canal:
Male
Anterior Wall: External Oblique Aponeurosis
Floor: Inguinal Ligament
Superficial inguinal ring: Defect in the external
oblique aponeurosis
Spermatic
cord
Roof: Arching fibres of transversus abdominis
and conjoint tendon
Deep inguinal ring: structures of the spermatic
cord pass through transversalis fascia
Posterior Wall: Transversalis fascia and
Conjoint tendon
The Inguinal Canal
Hesselbach’s Triangle: Common site for Direct Hernia
Inferior
HINT: Round ligament
medial/inferior and
often larger
Inguinal Canal: Female
Round
ligament
Round
ligament Ilioinguinal
nerve
Ilioinguinal
nerve
HINT: Usually visible
on top of spermatic
cord if it has been left
Ilioinguinal nerve: Male
uncut
The Scrotum
1. Using the spermatic cord as a guide
to location, cut through the skin
and reflect to reveal dartos fascia
➢Differentiated in relation
to the other layers OR
by the visible presence
of muscle fibres
Internal Spermatic fascia
➢Error in textbook*
HINT: Testicular artery
usually very tortuous
Pampiniform plexus
Visceral layer
HINT: Usually
smooth and shiny
compared to
fascia coverings
Testes
➢ Tunica albuginea
i. Usually demonstrated on a cross-
section of a testis because
visceral layer of tunica vaginalis
cannot be dissected from the
surface
ii. Thick, blue-grey outer covering of
the testis
➢ Seminiferous tubules
i. Production of spermatozoa
ii. Gives the tissue inside the testis
a kind of ‘fluffy’ appearance
Epididymis
Head
Body
Tail
Greater
omentum
Parietal Visceral
peritoneum peritoneum
Falciform ligament
Spleen
Liver
Left colic
flexure
Right colic
flexure Stomach
Ascending
Descending colon
colon
Transverse colon
Caecum Ileum
Falciform ligament
Liver
Stomach
Transverse colon
Jejunum
Ascending colon
Ileum
Sigmoid colon
Caecum
*The gloved finger is
traveling through
the Epiploic foramen
into the lesser sac
Lesser
Omentum
Liver
Hepato-duodenal
ligament (free
edge of lesser
omentum)
Sigmoid
mesocolon
Transverse Greater
colon omentum
(reflected (reflected
superiorly) superiorly)
Transverse
mesocolon
Appendix
Mesoappendix