Anatomy Lab - Unit 3, Week 1

Muscles, Vessels and Structures of the Abdomen

Diaphragm

Umbrella-like structure below the lungs

External Oblique

Outer surface of abdomen, fibers run down/in

Internal Oblique

Deeper abdomen, fibers run up/in

Transverse Abdominis

Deepest, fibers run transverse (horizontal)

Rectus Abdominis

Two parallel/vertical lines making up abs

Linea Alba

Line (ligament) between Rectus Abdominis (abs)

Rectus Sheath

Shiny layer on outer surface of abs

Inguinal Ligament

Groin ligament, runs from pubic tubercle to anterior superior iliac spinae

Psoas Major

Long, thick muscle deep in the abdominal wall, connects lumbar spine to the femur

Psoas Minor

Thin, slender muscle on the anterior surface of the psoas major muscle

Iliacus

Flat, triangular muscle lining inner bowl of pelvic bone, one of the body's primary hip flexors

Iliopsoas

Psoas major, Pasoas minor, and Iliacus combined

Quadratus Lumborum

Deepest muscle, fibers running down abdominal wall

Subcostal Nerve

Anterior ramus (ventral branch) of the T12 spinal nerve, the largest and last of the thoracic spinal nerves

Iliohypogastric Nerve

Mixed nerve originating from the lumbar plexus

Ilioinguinal Nerve

Provides motor and sensory innervation to the lower abdominal wall and external genitalia

Lateral Femoral Cutaneous Nerve of Thigh (LFCN)

Peripheral nerve supplying sensory feeling to outer/frontal thigh skin/areas

Femoral Nerve

One of the largest/most important nerves in the lower body

Genitofemoral Nerve

Mixed peripheral nerve originating from the lumbar plexus (spinal roots L1 and L2), runs downward, pierces the psoas major muscle, and divides into two main branches: the genital branch and the femoral branch

Obturator Nerve

Major peripheral nerve of lower body, originates from the lumbar plexus (spinal nerve roots L2, L3, and L4)

Descending Abdominal Aorta

Thick tube in the center of abdominal area

Celiac Artery

Top branch off the abdominal aorta

Superior Mesenteric Artery

Major anterior branch of abdominal aorta, supplies oxygen-rich blood to midgut

Infesior Mesenteric Artery

Third unpaired branch of abdominal aorta

Inferior Vena Cava

Largest vein in the human body, carries blood from the diaphragm to the right atrium

Hepatic Portal Vein(s)

Major blood vessel in the abdomen, carries nutrient-rich blood from the gastrointestinal tract, spleen, pancreas, and gallbladder directly to the liver for processing

Common Iliac Arteries/Veins

Located deep in the pelvis, supply and drain blood to the lower body and pelvic organs

External Iliac Arteries/Veins

Run alongside eachother to transport blood between the lower body and the heart

Internal Iliac Arteries/Veins

Supply and drain the pelvic viscera, walls, gluteal region, and perineum

Pudendal Nerve

Peripheral nerve in the pelvis, provides movement and sensation to the external genitals, perineum, anus, and surrounding pelvic floor muscles

Ganglion Impar (+Sympathetic Nerves)

Group of nerve cells in retroperitoneal space (anterior to where the tailbone meets the lower spine) and behind the rectum

Pelvis (Os Coxae)

Ilium, ischium, and pubis (hip bones)

Greater/False Pelvis

Rim of “hoop” and above

Lesser/True Pelvis

Net of “hoop” and down

Pelvic Inlet/Brim

Large opening of pelvis

Acetabulum

Cup-shaped socket of the hip, formed by fusion of Ilium, Ischium, and Pubis

Sacral Promontory (Pelvic Brim)

The anterior margin of the body of the first sacral vertebra (S1) where it projects forward into the pelvic cavity

Sacral Ala (Pelvic Brim)

Fan-shaped, wing-like projections on upper base of the sacrum, located on either side of the first sacral vertebra

Arcuate Line of Illium (Pelvic Brim)

Longest part of the side of the pelvic rim

Pecten Pubis

Prominent ridge located on the superior ramus of the pubic bone

Pubic Crest

Thick, rounded, superior border of the body of the pubis bone on the anterior (front) part of the hip bone

Ilium

Big fan portion of Os Coxa

Iliac Ala

Posterior face of fan

Iliac Fossa

Anterior face of fan

Iliac Crest