posterior abdominal wall is most important chapter in undergraduate curriculum.After read the above presentation you have to able describe about posterior abdominal wall structures like Muscles ,Bony part and Ligamental part. Then nervous innervation of Lumbarplexus and Autonomic nervous system of posterior abdominal wall including sympathetic chain

1. POSTERIOR ABDOMINAL WALL
THORACOLUMBAR FASCIA (AN 45.1)
MUSCLES (AN 45.3)
LUMBAR PLEXUS AND ABDOMINAL PART OF AUTONOMIC
SYSTEM (AN 47.12)
Dr .M.Vasanthakohila
Post graduate Department ofAnatomy
Kilpauk medical college

12. THORACOLUMBAR FASCIA
• It is divided into 2 parts –
lumbar and thoracic
• Lumbar fascia is the deep
fascia enclosing the deep
muscles of the back
• It is made up of 3 layers -
posterior, middle and
anterior
• It fills the gap between
12th rib and iliac crest

13. Contd…
• The posterior layer is
thickest and the
anterior layer is
thinnest
• The posterior layer
covers the loin and is
continued upwards on
the back of the thorax
and neck
• The middle and anterior
layers are confined to the
lumbar region

14. Contd…
• Between the posterior and
middle layers lie the erector
spinae and transversus
spinalis muscles
• Between the middle and
anterior layers lies the
quadratus lumborum muscle
• The 3 layers fuse laterally to
form a dense aponeurotic
sheet which gives origin to
the internal oblique and
transversus abdominis
muscles

15. POSTERIOR LAYER
• Medially - the layer is attached
to the tips of the lumbar and
sacral spines and the
interspinous ligaments.
• Laterally - it blends with the
middle layer at the lateral
border of the erector spinae.
• Superiorly - it continues on to
the back of the thorax where it
is attached to the vertebral
spines and the angles of the
ribs.
• Inferiorly - it is attached to the
posterior one-fourth of the
outer lip of the iliac crest.

16. MIDDLE LAYER
• Medially - the layer is attached to
the tips of the transverse
processes of first lumbar vertebra
and the inter-transverse
ligaments.
• Laterally - it blends with the
anterior layer at the lateral
border of the quadratus
lumborum.
• Superiorly - it is attached to the
lower border of the 12th rib and
to the lumbocostal ligament.
• Inferiorly - it is attached to the
posterior part of the intermediate
area of the iliac crest.

17. ANTERIOR LAYER
• Medially - the layer is attached
to the vertical ridges on the
anterior surface of the transverse
processes of first lumbar
vertebra.
• Laterally - it blends with the
middle layer at the lateral border
of the quadratus lumborum.
• Superiorly - it forms the lateral
arcuate ligament, extending from
the tip of the first lumbar
transverse process to the 12th
rib.
• Inferiorly - it is attached to the
inner lip of the iliac crest and the
iliolumbar ligament.

25. Iliohypogastric Nerve (L1)
• The nerve emerges @ the
lateral border of the psoas
major, runs downwards
and laterally in front of the
quadratus lumborum, and
behind the kidney and
colon, pierces the
transversus abdominis a
little above the iliac crest,
and runs in the abdominal
wall supplying the
anterolateral muscles.

26. Ilioinguinal Nerve (L1)
• The ilioinguinal
nerve (L1) has the
same course as the
iliohypogastric
nerve, but on a
slightly lower level
• It exits through
superficial inguinal
ring

27. ILIOINGUNIAL NERVE INNERVATIONS
MOTOR INERVATION
• INTERNAL OBLIQUE
MUSCLE
• TRANSVERSE ABDOMINIS
MUSCLE
SENSORY INNERVATION
• UPPER AND MDIAL ASPECT
OF THIGH
• SCROTUM AND ROOT OF
PENIS IN MALE
• MONS PUBIS AMD LABIA
MAJUS IN FEMALE

28. Genitofemoral nerve
• The nerve emerges on the
anterior surface of the psoas
muscle near its medial border
and runs downwards in front of
the muscle
• Near the deep inguinal ring it
divides into femoral and genital
branches
• The femoral branch passes
through the arterial
compartment of the femoral
sheath and is distributed to the
skin of the upper part of the
front of the thigh

29. Contd…
• The genital branch pierces
the psoas sheath and
enters the inguinal canal
through the deep inguinal
ring
• In the male, it supplies the
cremaster muscle, and in
the female, it gives sensory
branches to the round
ligament of the uterus and
to the skin of the labium
majus

30. Lateral cutaneous nerve of the thigh
• The nerve of the thigh
(L2, L3; dorsal divisions)
emerges at the lateral
border of the psoas, runs
downwards and laterally
across the right iliac
fossa, over the iliacus
and reaches the anterior
superior iliac spine
• Here it enters the thigh
by passing behind the
lateral end of the
inguinal ligament

31. Femoral nerve
• The femoral nerve (L2, L3, L4; dorsal divisions) emerges at
the lateral border of the psoas below the iliac crest, and runs
downwards and slightly laterally in the furrow between the
psoas and iliacus
• It lies under cover of the fascia iliaca
• It passes deep to the inguinal ligament to enter the thigh
lying on the lateral side of the femoral sheath
• Before entering the thigh it supplies the iliacus and
pectineus
• In thigh it supplies quadriceps femoris and sartorius

32. Obturator nerve
• The obturator nerve (L2, L3, L4; ventral divisions)
emerges on the medial side of the psoas muscle and
runs forwards and downwards on the pelvic wall,
below the pelvic brim
• Near its commencement it is crossed by the internal
iliac vessels and the ureter.
• It enters the thigh by passing through the obturator
canal.
• It supplies 3 adductor muscles, obturator externus
and gracilis.