Posterior Abdominal Wall- Exam III Flashcards
Describe the physical barrier between the abdominal and pelvic cavities?
No physical barrier- only arbitrary
What creates the ceiling, floor, and walls of the abdominopelvic cavity?
Ceiling- diaphragm
Floor- pelvic organs (bladder, uterus, rectum)
Posterior wall- bones of vertebral column (lumbar region), and muscles
Anterior lateral wall- muscle & connective tissue
Abdomen + pelvis =
One continuous space
Sheet of skeletal muscle and connective tissue that forms a physical barrier between the thorax & abdomen:
Diaphragm
What vertebra comprise the posterior abdominal wall?
T12-L5
Where do we consider the posterior abdominal wall to stop at?
Disc between L5 & sacrum
What does the hip bone break down into?
Ileum, Ischium, & pubis
Where does the inguinal ligament stretch between?
Pubic tubercle to iliac spine
Where is the obturator foramen & what passes through it?
Holes on either side of pubis & passageway for nerves
Part of the bony pelvis that is connected to the sacrum:
Ilium
Part of upper margin of ilium that is a blunt, curving, long ridge:
Iliac crest
The concavity below the iliac crest, facing the midline of the body:
Iliac fossa
Where the iliac crest comes to a point:
Anterior superior iliac spine
What do we consider our hip bones?
Anterior superior iliac spine
Label 1-8:
- Iliac crest
- Iliac fossa
- Anterior superior iliac spine
- Inguinal ligament
- Ilium
- Sacrum
- Obturator foramen
- Pubic tubercle
How far does the diaphragm come down into the abdominal cavity?
Rib 12
What muscle will form a large portion of the posterior abdominal wall?
Diaphragm
Describe the shape of the diaphragm:
Highly curbed arching dome
What do the upper abdominal organs attach to?
Posterior abdominal wall by sticking to the diaphragm
What two muscles of the posterior abdominal wall both attach to the transverse processes of lumbar vertebra?
Psoas major & quadratus lumborum
What posterior abdominal wall muscles function in lower limb movement?
(Muscles that cross the hip joint) Iliacus & psoas major
The quadratus lumborum primarily functions in what type of movement?
Primarily a lateral flexor of trunk
What is the practical function of the quadratus lumborum:
Trunk stabilization
Long & thick strong muscle that will originate from the transverse processes of the lumbar vertebra & 12th thoracic vertebra
Psoas major
A cylindrical muscle that comes from multiple origins on individual vertebra
Psoas major
Muscle that acts across the hip join & produces motions of the lower limb (although found in the abdominal & pelvis) and function mainly in lower limb movement
Psoas major
The psoas major comes down and narrows into a _____ that will cross the hip joint and insert into the ___.
Tendon; femur
Muscle that is located on the surface of the psoas major
Psoas minor
Thin mostly fibrous muscle that does NOT cross the hip joint, inserts on the front of the pelvis and may be associated with proprioception and some people don’t even have these
Psoas minor
Fan shaped muscle that is located within the iliac fossa
Iliacus
The iliacus crosses the hip joint to function in ____ limb movement and functions to _____.
Lower limb movement; flex the hip
Two posterior abdominal wall muscles that have the exact same function.
Iliacus & psoas major
Iliacus + psoas major
Iliopsoas
Tendons of what two posterior abdominal wall muscles fuse together?
Iliacus and psoas major
Muscle of the lower back that is lateral to the psoas minor:
Quadratus lumborum
The quadratus lumborum is named for:
It’s shape and location
What muscle has an origin coming off of the iliac crest
Quadratus lumborum
The quadratus lumborum has a free lateral margin that:
Doesn’t attach to anything
The quadratus lumborum has multiple insertions including:
12th rib & transverse processes of lumbar vertebra
On the transverse processes of the lumbar vertebra, describe the attachments of the quadratus lumborum and psoas major:
Psoas major attaches in front of the quadratus lumborum attachments
We tend to use the quadratus lumborum on:
One side at a time
When using the QL, we flex the trunk laterally toward:
The side where the QL is contracted
Does the QL function in lower limb movement? Why?
No, does not cross the hip joint
Origin of QL?
Iliac crest
The origin of the quadratus lumborum is considered _____. This is involved in teacup movement.
Stationary
The QL is active when _____ to help stabilize the trunk and control your center of gravity
Walking
Label
- Diaphragm
- Rib 12
- Iliac crest
- Iliacus
- Psoas minor
- Psoas major
- Quadratus lumborum
Are posterior abdominal wall deep intrinsic back muscle or hypaxial muscle?
Hypaxial muscles
because the posterior abdominal wall muscles are all hypaxial muscles they are all innervated by:
Ventral rami of spinal nerves
The muscles of the posterior abdominal wall need input from :
Multiple spinal cord levels
The quadratus lumborum is innervated by:
Ventral rami of spinal nerves T12- L4
How many different spinal cord levels are responsible for innervating the quadratus lumborum
5 levels
Both the psoas major and psoas minor are innervated by:
Ventral rami of spinal nerves L1 - L3
The iliacus is innervated by:
The femoral nerve
The femoral nerve is a combination of spinal cord levels:
L2, L3, L4
- Quadratus lumborum
- Psoas major
- Iliacus
The psoas major and iliacus tendons fuse together an go ______ to the hip joint.
Anterior
The psoas major originates off both:
Bodies and transverse processes of vertebra
Once the tendons of iliacus and psoas major fuse, where do they attach?
Lesser trochanter of femur
All of the muscles of the posterior abdominal wall are anterior to the:
Deep intrinsic back muscles
What two muscles are anterior to the QL?
Iliacus & psoas major
What is the origin of the QL?
Iliac crest near midline
Where does the QL instert/attach?
12th and transverse processes of lumbar vertebra
- Anterolateral abdominal wall mm
- Thoracolumbar fascia
- Quadratus fascia
- Psoas fascia
- Quadratus
- Iliocostalis
- Longissimus
4.multifidus - Psoas