Gross Anatomy of the Abdomen and Pelvis Flashcards
what bounds the anterolateral abdominal wall superiorly and inferiorly
Superiorly:
- 7th through 10th costal cartilages and xiphoid process
Inferiorly:
- Inguinal ligaments and the pelvic bones.
what will cause a narrow scar and what will cause a wide scar in relation to incisions made along or across a cleavage line
An incision along a cleavage line will heal as a narrow scar, while one that crosses the lines will heal as a wide scar
what is the cutaneous nerve supply of the anterolateral abdominal wall
Is derived from the anterior rami of the lower six thoracic and first lumbar nerves
what is the blood supply of the skin near the midline of the anterolateral abdominal wall
Skin near the midline is supplied by branches of the superior epigastric artery (br. of internal thoracic artery) and the inferior epigastric artery ( br. of external iliac artery)
what is the blood supply of skin of the flanks of the anterolateral abdominal wall
Skin of the flanks is supplied by branches from the intercostal, lumbar, and deep circumflex arteries
describe the two layers of superficial fascia of the anterolateral abdominal wall
Fatty layer or fascia of camper is continuous with the superficial fat over the rest of the body and may be extremely thick in obese patients
The membranous layer or scarpa’s fascia is thin and fades out laterally and above - this is located under the camper fascia
External oblique: origin insertion innervation action
- external surfaces of 5th-12th ribs (lower 8)
- linea alba, pubic tubercle, and iliac crest
- thoracic-abdominal nerves (T7-11 spinal nerves) and subcostal nerve
- compresses and supports abdominal viscera and flexes and rotates trunk
Internal oblique: origin insertion innervation action
- thoracolumbar fascia, iliac crest
- Linea alba, pubis, last 3 ribs
- thoraco-abdominal nerves (anterior rami of T6-T12 spinal nerves) and first lumbar nerve
- compresses and supports abdominal viscera and flexes and rotates trunk
Transversus abdominis: origin insertion innervation action
- Inguinal ligament, thoracolumbar fascia, cartilage of last 6 ribs, iliac crest
- Linea alba, pubis
- thoraco-abdominal nerves (anterior rami of T6-T12 spinal nerves) and first lumbar nerve
- Compress abdominal contents
Rectus abdominis: origin insertion innervation action
- Pubis
- Xiphoid process, costal cartilages of ribs 5-7
- thoraco-abdominal nerves (anterior rami of T6-T12 spinal nerves)
- trunk flexion
function of the Muscles of Anterolateral Abdominal Wall
Compress abdominal organs:
- raise intra-abdominal pressure: defecation, childbirth, micturition,flatulence, vomiting
- raise intra-thoracic pressure: laughing, coughing, shouting
Stabilize back (posture)
what type of tendon allows the internal oblique and transverses abdominis to insert together on the pubis
a conjoint tendon
Pyramidalis: origin insertion innervation action
what is abnormal about this muscle
pubis
linea alba
T12
tense linea alba
absent in 1/5 people
what are the contents of the rectus sheath
- Rectus abdominis
- Pyramidalis
- Anterior rami of T7-12
- Superior & inferior epigastric vessels
what intercostal nerves make up the thorax-abdominal nerves
T7-11
what makes the subcostal nerve
T12
at what level does the abdominal aorta divide into the L & R Common iliac arteries
L4
what forms the two lateral umbilical folds
due to underlying inferior epigastric vessels
what forms the two medial umbilical folds
ue to underlying medial umbilical ligaments (remnants of fetal umbilical arteries)
what forms the median umbilical fold
due to underlying median umbilical ligament
remnant of fetal urachus which drained urine from the bladder –> umbilicus
describe the Superficial lymphatic drainage of lymphatics above and below the umbilicus
above = axillary nodes
below = superficial inguinal nodes
describe the Deep lymphatic drainage of the abdomen
drain to deeper nodes and then drain to the cisterns chyli
what are the anterior border, posterior border, roof and floor of the inguinal canal
Anteriorly: Aponeurosis of External Oblique
& laterally reinforced by Internal Oblique lying superficial to the deep ring
Posteriorly: Transversalis fascia
& medially reinforced by the conjoint tendon lying posterior to the superficial ring
Roof: The arching fibers of the internal oblique & transversus abdominis
Floor: Inguinal ligament
how might an indirect inguinal hernia occur in males
Just before birth, the testes are pulled through the abdominal wall carrying with them a sac-like extension of the abdominal wall called the processus vaginalis
The connection between the abdomen & the sac surrounding the testicle should disappear - if NOT - Indirect inguinal hernia may result
