Plating 4 (Part 1)

Covers: diaphragm and abdominal walls

Diaphragm

Great muscloskeletal sheet that separates thoracic and abdominal cavities; primary muscle of respiration

5th rib

What rib does the diaphragm reach on its right side during moderate expiration?

5th interspace

What interspace does the diaphragm reach on its left side during moderate expiration?

Central tendon

Insertion of diaphragm

Sternal part

Origin of diaphragm consisting of small right & left slips arising from the posterior surface of the xiphoid process

Costal part

Origin of diaphragm consisting of six slips that arise from deep surfaces of the lower six ribs & their costal cartilages

Vertebral part

Origin of diaphragm arising by means of vertical columns or crura and from the arcuate ligaments

Caval opening

Esophageal hiatus

Aortic hiatus

3 diaphragm openings

Fibrous

Superior surface of the diaphragm tendon is partially fused with what layer of pericardium?

Right crus muscle fibers

These fibers act as a sphincter and likely help prevent regurgitation of stomach contents into the thoracic esophagus

Right crus

Arises from the sides of the bodies of the L1-3 & IV discs

Left crus

Arises from the sides of the bodies of the L1-2 & IV discs

Medial and lateral arcuate ligament

The diaphragm arises from what ligament

1. Muscle of inspiration

2. Muscle of abdominal straining

3. Weight-lifting muscle

4. Thoracoabdominal pump

Functions of the diaphragm

Muscle of inspiration

Function of the diaphragm where it pulls its central tendon down on contraction

Muscle of abdominal straining

Function of diaphragm where the contraction of the diaphragm assists the contraction of the muscles raising pressure for micturition, defecation, and parturition

T8

Dermatomal level of caval opening

Caval opening

Diaphragm opening that opens to IVC and right phrenic nerve

Esophageal opening / hiatus

Diaphragm opening that opens to esophagus

Aortic opening / hiatus

Diaphragm opening that opens to aorta, thoracic duct, and azygous vein

T10

Dermatomal level of esophageal opening

T12

Dermatomal level of aortic opening

Right and left phrenic nerves C3-C5

Motor nerve supply of diaphragm

Lower six intercostal nerves

Sensory nerve supply of the diaphragm

Thoracic side and abdominal side

Lymphatic supply of diaphragm

Hiccup

Involuntary spasmodic contraction of the diaphragm accompanied by the approximation of the vocal folds and closure of the glottis of the larynx; symptom of pleurisy, peritonitis, pericarditis, or uremia

Phrenic nerve C3–C5 injury. If an accessory phrenic nerve is present, the nerve to the subclavius must also be affected for complete paralysis.

What nerve injury can cause diaphragmatic paralysis?

C5 nerve / nerve to subclavius

Known as the accessory phrenic nerve when if affected, may obtain complete paralysis

Phrenicorraphy

Repair of penetrating injuries to diaphragm

Diaphragm injury

What should be suspected in a penetrating chest wound below the nipple level

Costal cartilages 7-12 + xiphoid process

What forms the superior border of the abdomen?

L4

Highest dermatomal level of iliac crest

L3-L4 IV disc

Dermatomal IV disc level of umbilicus

Diaphragm

Structure in superior abdominal wall

Pelvic inlet

Structure in inferior abdominal wall

Lumbar vertebrae

Structure in posterior abdominal wall, medially

12th ribs

Structure in posterior abdominal wall, laterally

Fascial envelope and parietal peritoneum

Abdominal wall linings

Deep fascia

Strongest abdominal wall layer

Parietal peritoneum

Outer layer of peritoneum in abdominal wall

1. Skin

2. Superficial fascia

3. Deep fascia

4. Muscles

5. Extraperitoneal fascia

6. Parietal peritoneum

Layers of the abdominal wall in order

False

True or false: skin is thicker in the ventral than dorsal

Umbilicus

Weakest part of abdomen situated in the linea alba

Camper’s fascia

Superficial fatty layer of superficial fascia

Scarpa’s layer

Deep membranous layer of superficial fascia

Dartos muscle

Fatty layer of superficial fascia in scrotum represented as thin layer of smooth muscle

Linea alba

Line located along the midline of anterior abdominal wall with CT raphe

Linea semilunaris

Along each lateral border of rectus abdominis

Linea transversa

Tendinous bands of rectus abdominis in the anterior abdominal wall

4

How many abdominal quadrants are there?

9

How many abdominal regions are there?

Gallbladder / right kidney / liver

Major organ in R. hypochondriac region

Liver

Stomach

Pancreas

Major organ/s in epigastric region

Spleen / left kidney / pancreas

Major organ in L. hypochondriac region

Ascending colon

Major organ in R. lumbar region

Small intestine

Transverse colon

Major organ in umbilical region

Descending colon

Major organ in L. lumbar region

Ileocecal junction

Appendix

Cecum

Major organ/s in R. inguinal region

Small intestine

Urinary bladder

Pregnant uterus

Major organ/s in hypogastric region

Sigmoid colon / small Intestine / left ovary and fallopian tubes / descending colon

Major organ/s in left inguinal region

Ventral rami of T7-L1

Cutaneous nerves of anterior abdominal wall

Azygous venous system

Venous drainage of anterior abdominal wall above umbilicus

Femoral system

Venous drainage of anterior abdominal wall below umbilicus

Axillary and sternal nodes

Lymphatic drainage of anterior abdominal wall above umbilicus

Superficial inguinal nodes

Lymphatic drainage of anterior abdominal wall below umbilicus

External oblique

Internal oblique

Transversus abdominus

Rectus abdominus

Muscle layers of anterior abdominal wall

Rectus sheath

Encloses rectus abdominus

Posterior abdominal wall

This wall extends from the 12th rib above to the pelvic brim below; it supports retroperitoneal organs, vessels, and nerves

Psoas major

Ilacus

Quadratus lumborum

Muscles of the posterior abdominal wall

Psoas major muscle

Muscle of posterior abdominal wall as the chief flexor of thigh at hip joint

Ventral rami L1-L3

Innervation of psoas major muscle

Psoas minor muscle

Posterior abdominal muscle present in ~50% individuals; weak flexor of the trunk

Iliacus

Posterior abdominal wall muscle that is fan-shaped and forms the lateral component of the iliopsoas muscle; flexion of the thigh and lumbar part of vertebral column

Quadratus lumborum

Posterior abdominal wall muscle that extends the lumbar vertebral column

Duodenum 2nd and 3rd parts

Pancreas

Kidneys & ureters

Suprarenal glands

Organs in the posterior abdominal wall

Abdominal aorta and IVC

Great vessels of the abdomen

IVC

Formed by the union of right and left common iliac veins

External iliac

Common iliac

Aortic lymph nodes

Lymph nodes of posterior abdominal wall

Psoas fascia

Iliac fascia

Thoracolumbar fascia

Fascia of posterior abdominal walls

Thoracolumbar fascia

Fascia of posterior abdominal walls where it extends from the back of sacrum to the neck; its lumbar part medially splits into three layers

Psoas fascia

Thick fascia of posterior abdominal walls surrounding the psoas muscle

11th-12th rib

12th vertebra

Sacrum

IV discs

Skeleton of the posterior abdominal wall

Psoas abscess

Tubercular infection of the thoracolumbar vertebrae, causing destruction of the vertebral bodies

Aortic aneurysm

Localized dilation of the aorta; most common cause of this is atherosclerosis, which weakens the aortic wall

Last / 3rd trimester

The IVC is commonly compressed by an enlarged uterus during what period of pregnancy?

Compression of IVC

Causes edema of the ankle and feet, and varicose veins in the lower limb

Superior epigastric arteries / inferior epigastric arteries

Arterial supply of anterior abdominal wall above umbilicus

Superficial epigastric arteries / superficial iliac arteries

Arterial supply of anterior abdominal wall below umbilicus

L1 spinal nerves

Innervation of psoas minor muscle

Ventral rami T12-L3

Innervation of quadratus lumborum

Femoral nerve

Innervation of iliacus