Unit 9 - Abdomen and Pelvis Flashcards
Name this bone marking
Greater sciatic foramen (anterior view)
Only visible when ligaments (soft tissue) are in view.
Name this bone marking
Greater sciatic foramen (posterior view)
Only visible when ligaments (soft tissue) are in view
Name this bone marking
Lesser sciatic foramen (posterior-latero view)
Only visible when:
- Ligaments (soft tissue) are in view
- On certain angles: lateral and posterior views are best for viewing.
Name this bone marking
Pelvic Inlet
i.e. Superior pelvic aperture
Name this bone marking
Pelvic outlet
i.e. Inferior pelvic aperture
Identify this bone marking
What muscle attaches here?
Obturator foramen
Obturator internus
Identify this bone marking
sacrococcygeal notch
Name this structure
Pubis
*Bottom third of the acetabulum helps mark where pubis begins
Identify these 2 regions
Superior and inferior pubic ramus
Roughly trace out the outlines of the superior and inferior pubic ramus
Name this bone marking
Crest of the pubic bone
Crest: A raised or prominent part of the edge of a bone. Crests are often the sites where connective tissue attaches muscle to bone.
Roughly trace the crest of the pubic bone
Name this region
Body of the pubis
Roughly trace the body of the pubic bone
Name this bone marking
Iliac fossa
Fossa: A shallow depression in the bone surface.
Roughly trace the fossa of the ilium.
Also, state if this is a male or female pelvis.
Male pelvis
Ways to distinguish:
Female:
- Bones are lighter and thinner.
- Pelvic inlet shape: round/oval
- Lesser pelvic cavity is shorter and wider.
- Subpubic angle: greater in females (>80*)
- Pelvic outlet rounded & larger.
- Sacrum: wider, shorter, less curved.
Male:
- Bones thicker & heavier.
- Pelvic inlet heart-shaped.
- Lesser pelvic cavity is longer & narrower.
- Subpubic angle: less than 70*
- Pelvic outlet: smaller
Name this region
Auricular (articular) surface of the ilium
Identify the auricular (articular) surface of the ilium
Identify if this is a male or female pelvis
Female pelvis
Ways to distinguish:
Female:
- Bones are lighter and thinner.
- Pelvic inlet shape: round/oval
- Lesser pelvic cavity is shorter and wider.
- Subpubic angle: greater in females (>80*)
- Pelvic outlet rounded & larger.
- Sacrum: wider, shorter, less curved.
Male:
- Bones thicker & heavier.
- Pelvic inlet heart-shaped.
- Lesser pelvic cavity is longer & narrower.
- Subpubic angle: less than 70*
- Pelvic outlet: smaller
Roughly trace the location of the ala of the ilium
Ala = “wing”
What is this bone marking?
Greater sciatic notch (lateral view)
What is this bone marking?
Iliac crest (anterior view)
Crest: A raised or prominent part of the edge of a bone. Crests are often the sites where connective tissue attaches muscle to bone
What is this region?
Ala of the ilium
Roughly trace the iliac crest
Crest: A raised or prominent part of the edge of a bone. Crests are often the sites where connective tissue attaches muscle to bone
What is this region?
Body of the ilium
Roughly trace the body of the ilium
What is this bone marking?
Lesser sciatic notch
What is this?
Pubic symphysis (posterior view)
What is this?
Acetabulum (lateral view)
What region is this?
Body of the ischium
Roughly trace the body of the ischium
What region is this?
Ramus of ischium
What region is this?
Ramus of ischium
Roughly trace the ramus of the ischium
Name this region
Ischial spine
Roughly trace the spine of the ischium
Name this bone marking
Ischial tuberosity
Tuberosity: a rounded prominence especially : a large prominence on a bone usually serving for the attachment of muscles or ligaments.
Roughly trace the location of the ischium
Identify this structure
sacrum
Name this region
base of the sacrum
Name this region
Median sacral crest
Name this region
Intermediate sacral crest
Name this region
Intermediate sacral crest
Name this region
Lateral sacral crest
Name this bone marking
Sacral foramina
Name this region
Apex of the sacrum
Name this structure
Coccyx
Name this structure
Coccyx
Name this region
Base of coccyx
Name this region
apex of the coccyx
Name this structure
Posterior sacrococcygeal ligament (deep portion)
Name this structure
Posterior sacrococcygeal ligament (superficial portion)
- Name this structure
- What does it connect?
- What is its function?
Inguinal ligament
Attachment points:
- anterior superior iliac spine of the ilium
- pubic tubercle on the pubic bone.
Function:
- Attach external oblique muscle to the pelvis
- Name this structure
- What does it connect?
- What is its function?
Inguinal ligament
Attachment points:
- anterior superior iliac spine of the ilium
- pubic tubercle on the pubic bone.
Function:
- Attach external oblique muscle to the pelvis
- Name this structure
- What does it connect? (origin/insertion)
- What is its function?
Sacrospinous ligament
Attachment points:
- Origin: border of lower sacral and upper coccygeal segments (anterior to sacrotuberous ligament)
- Insertion: ischial spine
Function:
- Provide stability to the pelvis: prevents rotation of the illum past the sacrum
- Name this structure
- What does it connect? (origin/insertion)
- What is its function?
Sacrotuberous ligament
Attachment points:
- Proximal attachments: Posterior ilium, lateral sacrum and coccyx
- Distal attachment: Ischial tuberosity
Function:
- provide stabilization of the sacroiliac joint
- strengthen connection between bony pelvis and vertebral column
- Name this structure
- What does it connect? (origin/insertion)
- What is its function?
iliolumbar ligament
Origin: transverse processes of the L4 & L5 vertebrae
Insertion: iliac tuberosity and iliac crest
Function: stabilizes lumbosacral joint
- Name this structure
- What does it connect? (origin/insertion)
- What is its function?
Anterior sacro-iliac ligament
Attachments:
- ala of ilium
- pelvic surface of the sacrum
Function: stabilize the sacroiliac joint
- Name this structure
- What does it connect? (origin/insertion)
Posterior sacro-iliac ligament
3 bands:
- interosseous sacroiliac ligament: tuberosities of the sacrum and ilium
- short posterior sacroiliac ligament:
◘ origin at 1st and 2nd transverse tubercles of the sacrum
◘ insert: tuberosity of the ilium - Long posterior sacroiliac ligament:
◘ posterior iliac spine to the 3rd and 4th transverse tubercles of the sacrum
- Name this structure
- What does it connect? (origin/insertion)
- What is its function?
superior pubic ligament
attachment: superior aspect of the symphysis –> pubic tubercles
Function: strengthen interpubic joint
- Name this structure
- What does it connect? (origin/insertion)
- What is its function?
inferior pubic ligament
attachment: inferior aspect of symphysis
Function: strengthen interpubic joint
- Name this structure
- What does it connect? (origin/insertion)
- What is its function?
anterior sacrococcygeal ligament
attachments: anterior surface of sacrum to anterior surface of apex of coccyx
function: stabilize sacrococcygeal joint
- Name this structure
- What does it connect? (origin/insertion)
- What is its function?
Superficial Posterior sacrococcygeal ligament
attachments: margin of sacral hiatus –> dorsal surface of coccyx
Function: stabilize sacrococcygeal joint
- Name this structure
- What does it connect? (origin/insertion)
- What is its function?
deep posterior sacrococcygeal ligament
attachments: dorsal surface of 5th sacral segment –> dorsal surface of coccyx
function: stabilize sacrococcygeal joint
- Name this muscle
- Origin/insertion
- Function
Obturator internus
- Origin: ischial pubic ramus
- Insertion: medial surface of the greater trochanter of femur
Function:
- external rotation of thigh at the hip joint
- abduction of the flexed thigh at the hip joint
- Stabilize hip joint by keeping the head of the femur within the acetabulum
Fan shaped
- Name this muscle
- Origin/insertion
- Function
- Innervation
- Blood supply
Piriformis muscle (posterior view)
Origins:
- anterior surface of sacrum (between S2 and S4)
- Gluteal surface of ilium (near posterior inferior iliac spine)
- Sacrotuberous ligament
Insertion:
- apex of the greater trochanter of the femur
Function:
- external rotation of thigh
- abduction (from flexed hip) of the thigh
- Stabilize head of femur in acetabulum
Innervation: nerve to piriformis (S1-S2)
Blood supply:
- superior gluteal artery
- inferior gluteal artery
- gemellar branches of the internal pundendal
- Name this muscle
- Origin/insertion
- Function
- Innervation
- Blood supply
Levator ani muscle (3 muscles)
◘ puborectalis
◘ pubococcygeus
◘ iliococcygeus
Origin
◘ Puborectalis: posterior surface of body of pubic bone
◘ Pubococcygeus: posterior surface of body of pubic bone
◘ iliococcygeus: tendinous arch of internal obturator fascia + ischial spine
Insertion:
◘ Puborectalis: None (forms ‘puborectal sling’ posterior to rectum)
◘ Pubococcygeus: Anococcygeal ligament, Coccyx, Perineal body and musculature of prostate/ vagina
◘ Iliococcygeus: Anococcygeal ligament, Coccyx
Function:
- Stabilize abdominal cavity and pelvic organs
Innervation:
- Nerve to levator ani (S4); - — Pubococcygeus also receives branches via inferior rectal/ perineal branches of Pudendal nerve (S2- S4)
- Name this muscle
- Origin/insertion
- Function
- Innervation
- Blood supply
Levator ani muscle (3 muscles)
◘ puborectalis
◘ pubococcygeus
◘ iliococcygeus
Origin
◘ Puborectalis: posterior surface of body of pubic bone
◘ Pubococcygeus: posterior surface of body of pubic bone
◘ iliococcygeus: tendinous arch of internal obturator fascia + ischial spine
Insertion:
◘ Puborectalis: None (forms ‘puborectal sling’ posterior to rectum)
◘ Pubococcygeus: Anococcygeal ligament, Coccyx, Perineal body and musculature of prostate/ vagina
◘ Iliococcygeus: Anococcygeal ligament, Coccyx
Function:
- Stabilize abdominal cavity and pelvic organs
Innervation:
- Nerve to levator ani (S4);
- Pubococcygeus also receives branches via inferior rectal/ perineal branches of Pudendal nerve (S2- S4)
Blood supply:
- Inferior gluteal artery
- inferior vesical artery
- pudendal artery
- Name this muscle
- Origin/insertion
- Function
- Innervation
- Blood supply
Coccygeus muscle
Origin: ischial spine
Insertion: inferior end of sacrum and coccyx
Function:
- supports pelvic viscera
- flexes the coccyx
Innervation: anterior rami of spinal nerves S4 & S5
Blood supply:
- Inferior vesical artery
- inferior gluteal artery
- pudendal artery
- Name this muscle
- Origin/insertion
- Function
- Innervation
- Blood supply
External oblique muscle
◘ most superficial (lies superficial to the internal oblique muscle and the transverse abdominis muscles)
Origin: external surfaces of ribs 5-12
Insertion:
- linea alba (connective tissue)
- pubic tubercle
- anterior half of iliac crest
Function:
- trunk flexion
- Expiration
- compresses abdominal viscera
- trunk lateral flexion (ipsilateral)
- trunk rotation (contralateral)
Innervation:
- Motor nerves:
◘ intercostal nerves T7-T11
◘ Subcostal nerve (T12)
- Sensory nerve: iliohypogastric nerve (L1)
Blood supply:
- Lower posterior intercostal arteries
- subcostal artery
deep circumflex iliac artery
- Name this muscle
- Origin/insertion
- Function
- Innervation
- Blood supply
Internal oblique muscle:
- Lies deep to external oblique muscle
- Lies superficial to the transverse abdominis muscle
Origin:
- anterior two-thirds of iliac crest
- iliopectineal arch
- thoracolumbar fascia
Insertion:
- inferior borders of ribs 10-12
- linea alba (connective tissue)
- pubic crest
- pectin pubis
Function:
- Bilateral contraction - Trunk flexion, compresses abdominal viscera, expiration
- Unilateral contraction - Trunk lateral flexion (ipsilateral), trunk rotation (ipsilateral)
Innervation:
- Intercostal nerves (T7-T11)
- Subcostal Nerve (T12)
- iliohypogastric nerve (L1)
- ilioinguinal nerve (L1)
Blood supply:
- lower posterior intercostal artery
- subcostal artery
- superior epigastric artery
- inferior epigastric artery
- superficial circumflex artery
- deep circumflex artery
- posterior lumbar artery
- Name this muscle
- Origin/insertion
- Function
- Innervation
- Blood supply
Transverse abdominis
Origin:
- Internal surface of costal cartilages of ribs 7-12
- thoracolumbar fascia
- anterior two thirds of iliac crest
- iliopectineal arch
Insertion:
- linea alba (connective tissue)
- aponeurosis of internal abdominal oblique muscle
- pubic crest
- pectinal line of pubis
Function:
- Bilateral contraction - Compresses abdominal viscera, expiration
- Unilateral contraction - Trunk rotation (ipsilateral)
Innervation:
- Intercostal nerves (T7-T11)
- subcostal nerve (T12)
- iliohypogastric nerve (L1)
- ilioinguinal nerve (L1)
Blood supply:
- Lower posterior intercostal and subcostal arteries
- superior and inferior epigastric arteries
- superficial and deep circumflex arteries
- posterior lumbar arteries
- Name this muscle
- Origin/insertion
- Function
- Innervation
- Blood supply
Rectus abdominis
Origin:
- pubic symphysis
- pubic crest
Insertion:
- Xiphoid process
- Costal cartilages of ribs 5-7
Function:
- Trunk flexion
- compresses abdominal viscera
- expiration
Innervation:
- Intercostal nerves (T7-T11)
- subcostal nerve (T12)
Blood supply:
- Inferior epigastric and superior epigastric arteries
- contributions from posterior intercostal
- subcostal and deep circumflex arteries
- Name this muscle
- Origin/insertion
- Function
- Innervation
- Blood supply
Diaphragm
Origin:
- Sternal part: Posterior aspect of xiphoid process
- Costal part: Internal surfaces of lower costal cartilages and ribs 7-12
- Lumbar part: Medial and lateral arcuate ligaments (lumbocostal arches), bodies of vertebrae L1-L3 (+intervertebral discs), anterior longitudinal ligament
Insertion: Central tendon of diaphragm
Function:
- Depress the costal cartilages
- Breathing
Innervation:
- Phrenic nerves (C3-C5) (sensory innervation of peripheries via 6th-11th intercostal nerves)
Blood supply:
- Subcostal and lowest 5 intercostal arteries
- inferior phrenic arteries
- superior phrenic arteries
- Name this nerve
- its origin
- what it innervates
- its branches
Iliohypogastric nerve
Origin: Lumbar plexus (L1)
Innervation:
- Motor:
◘ Transverse abdominis
◘ internal oblique
◘ conjoint tendon.
Sensory:
◘ External oblique
◘ internal oblique
◘ transverse abdominis
◘ Skin of the suprapubic region and posterolateral aspect of gluteal region.
Branches: it splits into 2 branches as it passes between the transverse abdominis and internal oblique:
- lateral cutaneous branch
- anterior cutaneous branch
- Name this nerve
- its origin
- what it innervates
- its branches
ilio-inguinal nerve
origin: lumbar plexus (inferior branch of anterior ramus of spinal nerve L1)
Supply:
- Motor:
◘ Internal oblique muscle
◘ transversus abdominis muscle
- Sensory: Skin of proximal medial thigh, mons pubis, labium majus and root of the clitoris; anterior scrotum and root of the penis
Branches:
- Anterior labial nerves
- anterior scrotal nerves
Define the boundaries of the greater (false) pelvis
Location:
- superior to the pelvic inlet
- contains distal part of the intestines
Borders:
- Lateral border: ala of the ilium
- posterior border:
◘ 4th & 5th lumbar vertebrae
◘ base of sacrum
- Anterior border:
◘ inferior part of the anterior abdominal wall
Define the boundaries of the lesser (true) pelvis
Location:
- between the pelvic inlet and pelvic outlet
- contains the internal genitalia, perineum, and distal organs of the urinary tract
Borders:
- Lateral: ilioischial complex
- Posterior: sacrococcygeal complex
- Anteroinferior:
◘ Pubic bones
◘ Pubic symphysis
Abdomen:
- Name its boundaries
- Name its contents
Boundaries: anterolateral and posterior abdominal walls, diaphragm, pelvic inlet
Contents: stomach, small intestine, large intestine, vermiform appendix, pancreas, spleen, liver, gallbladder, kidneys, ureters, adrenal glands
