I described about the whole anatomy of anterolateral abdominal wall. Muscles, ligaments attach directly to anterolateral abdominal wall. Also add the topic of inguinal canal complete.

1. Muscles Of Anterolateral
Abdominal Wall and Inguinal canal
DR AQSA AROOB

2. TRANSVERSUS ABDOMINIS
• Innermost of the three flat abdominal muscles
• ideal for compressing the abdominal contents,
increasing intra-abdominal pressure.
• transversus abdominis muscle also end in an
aponeurosis, which contributes to the formation
of the rectus sheath
• Between the internal oblique and the transversus
abdominis muscles is a neurovascular plane
• It contains the nerves and arteries supplying the
anterolateral abdominal wall

4. RECTUS ABDOMINIS MUSCLE
• A long, broad, strap-like muscle, is the
principal vertical muscle of the anterior
abdominal wall.
• it is broad and thin superiorly and narrow and
thick inferiorly.
• Most of the rectus abdominis is enclosed in
the rectus sheath.

7. PYRAMIDALIS
• a small, insignificant triangular muscle that is
absent in approximately 20% of people.
• attaches to the anterior surface of the pubis
and the anterior pubic ligament. It ends in the
linea alba, which is especially thickened for a
variable distance superior to the pubic
symphysis
• a landmark for median abdominal incision

9. RECTUS SHEATH, LINEA ALBA, AND
UMBILICAL RING
• The rectus sheath is the strong, incomplete fibrous
compartment of the rectus abdominis and pyramidalis
muscle.
• Also found in the rectus sheath are the superior and
inferior epigastric arteries and veins, lymphatic vessels,
and distal portions of the thoraco-abdominal nerves.
• rectus sheath is formed by the decussation and
interweaving of the aponeuroses of the flat
abdominal muscles.
• external oblique aponeurosis contributes to the
anterior wall of the sheath throughout its length.

10. • Throughout the length of the sheath, the
fibers of the anterior and posterior layers of
the sheath interlace in the anterior median
line to form the complex linea alba.
• The linea alba, running vertically the length of
the anterior abdominal wall and separating
the bilateral rectus sheaths

13. • . The linea alba transmits small vessels and
nerves to the skin.
• umbilical ring, a defect in the linea alba
through which the fetal umbilical vessels
passed to and from the umbilical cord and
placenta.

14. FUNCTIONS AND ACTIONS OF ANTEROLATERAL
ABDOMINAL MUSCLES
• strong expandable support for the
anterolateral abdominal wall.
• support the abdominal viscera and protect
them from most injuries.
• compress the abdominal contents to
maintain or increase the intra-abdominal
pressure and, in so doing, oppose the
diaphragm
• move the trunk and help to maintain posture.

15. • The oblique and transverse muscles, acting
together bilaterally, form a muscular girdle
that exerts firm pressure on the abdominal
viscera.
• elevates the relaxed diaphragm to expel air
during respiration and more forcibly for
coughing, sneezing, nose blowing, voluntary
eructation (burping), and yelling or screaming

16. • The combined actions of the anterolateral
muscles also produce the force required for
defecation (discharge of feces), micturition
(urination), vomiting, and parturition
(childbirth).
• movements of the trunk at the level of the
lumbar vertebrae and in controlling the tilt of
the pelvis

17. Neurovasculature of Anterolateral
Abdominal Wall
• Thoraco-abdominal nerves: inferior six
thoracic spinal nerves (T7–T11)
• Lateral (thoracic) cutaneous branches of the
thoracic spinal nerves T7–T9 or T10.
• Subcostal nerve: the large anterior ramus of
spinal nerve T12.
• Iliohypogastric and ilio-inguinal nerves:
terminal branches of the anterior ramus of
spinal nerve L1.

19. • T7–T9 supply the skin superior to the
umbilicus. T10 supplies the skin around the
umbilicus. T11, plus the cutaneous branches
of the subcostal (T12), iliohypogastric, and ilio-
inguinal (L1), supply the skin inferior to the
umbilicus.

20. VESSELS OF ANTEROLATERAL
ABDOMINAL WALL
• Superior epigastric vessels and branches of
the musculophrenic vessels from the internal
thoracic vessels.
Inferior epigastric and deep circumflex iliac
vessels from the external iliac vessels.
Superficial circumflex iliac and superficial
epigastric vessels from the femoral artery and
greater saphenous vein.

21. • The major arteries of the anterolateral abdominal
wall are the
• superior epigastric
• inferior epigastric
• musculophrenic
• subcostal
• posterior intercostal arteries
• deep circumflex iliac artery
• superficial circumflex iliac artery
• superficial epigastric artery.

25. • superior epigastric
artery
• Inferior epigastric artery
• superior part of the
rectus abdominis
• lower rectus abdominis

27. Clinical case-Abdominal Hernia
• Anterolateral abdominal wall may be the site
of abdominal hernias.
• inguinal, umbilical, and epigastric regions
• Umbilical hernias are common in neonates
• Acquired umbilical hernias occur most
commonly in women and obese people.
• epigastric hernia-typically just lobules of fat.
They are often painful, especially if a nerve is
compressed.

29. Internal Surface of Anterolateral
Abdominal Wall
• covered with transversalis fascia, a variable
amount of extraperitoneal fat, and parietal
peritonium.
• infra-umbilical part of this surface exhibits five
umbilical peritoneal folds passing toward the
umbilicus

31. • The median umbilical fold extends from the apex
of the urinary bladder to the umbilicus and
covers the median umbilical ligament
• Two medial umbilical folds, lateral to the median
umbilical fold, cover the medial umbilical
ligaments, formed by occluded parts of the
umbilical arteries.
• Two lateral umbilical folds, lateral to the medial
umbilical folds, cover the inferior epigastric
vessels and therefore bleed if cut.

32. • Supravesical fossae-between the median and the
medial umbilical folds
• Medial inguinal fossae-between the medial and
the lateral umbilical folds, areas also commonly
called inguinal triangles (Hesselbach triangles),
potential sites for the less common direct
inguinal hernias
• Lateral inguinal fossae-lateral to the lateral
umbilical fold, most common type of hernia in
the lower abdominal wall, the indirect inguinal
hernia

33. Inguinal Region
• The inguinal region (groin) extends between
the ASIS and pubic tubercle.
• important area anatomically and clinically:
• Anatomically because it is a region where
structures exit and enter the abdominal cavity
and clinically because the pathways of exit
and entrance are potential sites of herniation.

37. INGUINAL LIGAMENT
• inguinal ligament is the thickened,
underturned, inferior margin of the
aponeurosis of the external oblique, forming
a retinaculum that bridges the subinguinal
space.

38. INGUINAL LIGAMENT AND ILIOPUBIC
TRACT
• Thickened fibrous bands, or retinacula, occur
in relationship to many joints.
• The inguinal ligament and iliopubic tract,
extending from the ASIS to the pubic tubercle,
constitute a bilaminar anterior (flexor)
retinaculum of the hip joint.

39. • The retinaculum spans the subinguinal space,
through which pass the flexors of the hip and
neurovascular structures serving much of the
lower limb.
• These fibrous bands are the thickened
inferolateral-most portions of the external
oblique and aponeurosis and the inferior
margin of the transversalis fascia.

40. • The inguinal ligament is a dense band
constituting the inferiormost part of the
external oblique aponeurosis. Although most
fibers of the ligament’s medial end insert into
the pubic tubercle.
• lacunar ligament (of Gimbernat), which forms
the medial boundary of the subinguinal space.

41. • The inguinal ligament is the thickened,
underturned, inferior margin of the
aponeurosis of the external oblique, forming a
retinaculum that bridges the subinguinal
space.

43. iliopubic tract
• Iliopubic tract is the thickened inferior margin
of the transversalis fascia, which appears as a
fibrous band running parallel and posterior
(deep) to the inguinal ligament
• The inguinal ligament and iliopubic tract span
and provide central strength to an area of
innate weakness in the body wall in the
inguinal region called the myopectineal orifice

44. INGUINAL CANAL
• Oblique passage, approximately 4 cm long,
directed inferomedially through the inferior part
of the anterolateral abdominal wall.
• lies parallel and superior to the medial half of the
inguinal ligament.
• The main occupant of the inguinal canal is the
spermatic cord in males and the round ligament
of the uterus in females.
• inguinal canal also contains blood and lymphatic
vessels, the ilio-inguinal nerve, and the genital
branch of the genitofemoral nerve

46. BOUNDRIES
• Anterior Wall
• In whole extend;
• Skin
• Superfascial fascia
• External oblique muscle
• In its lateral 1/3rd
• Fleshy fibres of internal oblique muscle

47. Posterior wall
• In whole extend
• Fascia transversalis
• Extra peritoneal tissue
• Parietal peritonium
• Its medial 2/3rd
• Conjoint tendon

48. • ROOF
• Internal oblique and transversus abdominus
• FLOOR
• Inguinal and lacunar ligament

49. Structures passing through canal
• Spermatic cord in male
• Round ligament of uterus in female
• Enters the inguinal canal through deep
inguinal ring and passes out through
superficial inguinal ring.
• Ilioinguinal nerve- enters the canal between
internal and external oblique muscles and
passes out the superficial inguinal ring.

50. • deep (internal) inguinal ring
• superficial (external) inguinal ring

51. Deep (internal) inguinal ring
• deep (internal) inguinal ring is the entrance to the
inguinal canal.
• located superior to the middle of the inguinal
ligament and lateral to the inferior epigastric
artery
• evagination in the transversalis fascia that forms
an opening like the entrance to a cave
• The transversalis fascia itself continues into the
canal, forming the innermost covering (internal
fascia) of the structures traversing the canal.

52. superficial (external) inguinal ring
• the exit by which the spermatic cord in males,
or the round ligament in females, and ilio-
inguinal nerve emerge from the inguinal canal.

53. Consitituents of spermatic cord
• Ductus deference
• Testicular artries
• Cremastaric arteries
• Pampiniform plexus of veins
• Lymph vessels
• Ilioinguinal nerve
• Genital branch of genitofemoral nerve
• Processus veginalis

54. Coverings of spermatic cord
• Internal spermatic fascia-derived from fascia
transversalis
• Creamstaric fascia- internal oblique and
transversus abdominis
• External spermatic fascia-external oblique
aponeurosis.

55. Spermatic cord Contents
• 3 arteries;
• Testicular artery, artery of ductus deference
• Cremastaric artery
• 3 nerves:
• Genitofemoral nerve, ilioinguinal nerve, autonomic
nerve
• 3 other structures
• Panpiniform plexus(loose network of small veins)
• Ductus deference( fibromuscualar tube and excretory
duct of testis)
• Processus vaginalis

56. Mechanism of inguinal canal
• Flap valve Mechanism- Anterior/Posterior
approximation( External oblique muscle)
• Shutter mechanism- Floor/Roof
approximation(Transversus fibres)
• Slit valve mechanism-two superificial ring
cruras approximation(external oblique)
• Ball valve mechanism- spermatic cord
protection(cremastaric muscle)

57. Inguinal canal Development
• Canal is very short in early life as pelvis
increases in width, deep inguinal shifts
laterally and adult dimensions of canal are
attained