Pelvis - Lecture 5 Flashcards
What are the Bones of the Pelvic Cavity?
- Pelvic Bones (2)
- Sacrum
- Coccyx
What fused bones make up each Pelvic Bone?
- Ilium (Superior)
- Ischium (Inferior Posterior)
- Pubis (Inferior Anterior)
Acetabulum
Cup-shaped depression on the lateral surface of the pelvic bones where the head of the femur articulates
Which two parts of the Pelvis are located Anteriorly in the same plane?
- Anterior Superior Iliac Spine
2. Pubic Tubercle
What is the name of the Anterior vertical plane on the Pelvis that joins the two Pelvic Bones?
Pubic Symphysis
What pats of the Ilium are palpable?
- Anterior Superior Iliac Spine (ASIS)
2. Iliac Crest
What is the name of the thickened ridge at the top of the Ilium?
Iliac Crest
Name the Components of the Pelvis
- Iliac Spine
- Anterior Superior Iliac Spine
- Anterior Inferior Iliac Spine
- Posterior Superior Iliac Spine
- Posterior Inferior Iliac Spine
- Iliac Fossa
- Greater Sciatic Notch
- Lesser Sciatic Notch
- Ischial Spine
- Ischial Tuberosity
- Obturator Foramen
- Superior Pubic Ramus
- Inferior Pubic Ramus (Ischia Pubic Ramus)
- Pubic Tubercle
Where does the Sacrum articulate with the Pelvic bones?
Between the Posterior Superior Iliac Spine and the Posterior Inferior Iliac Spine
Which muscle originates on the Iliac Fossa?
Iliacus
What is the Greater Sciatic Notch used for?
Space allowing structures to pass from inside Pelvis to the Gluteal region
What does the Ischial Spine separate?
Ischial Spine separates the Greater Sciatic Notch from the Lesser Sciatic Notch
Which bone you sit down on?
Ischial Tuberosity
What is the Obturator Foramen?
An opening in the inferior portion of the Pelvis that is mostly covered by a membrane, but has space for the Obturator Artery, Vein, and Nerve to pass through
What innervates the Medial Thigh?
Obturator Nerve
What innervates the Anterior Thigh?
Femoral Nerve
What structures surround the Obturator Foramen?
- Superior Pubic Ramus
2. Inferior Pubic Ramus (AKA Ishia Pubic Ramus
What attaches to the ASIS and the Pubic Tubercle?
Inguinal Ligament
Where does the Inguinal Ligament come from?
Extension of the External Oblique Aponeurosis
Sacro-Iliac Joint
Posteriorly where the medial side of the two pelvic bones are connected to the Sacrum
Pubic Symphysis
Anteriorly where the two Pelvic Bones are connected by dense fibrocartilage
Which direction is the Pelvis tilted and why?
It is tilted anteriorly so the ASIS and the Pubic Tubercles are located in the same plane
Pubic Angle
Angle formed by the two pubic bones ANTERIORLY
Pelvic Inlet
The imaginary Plane formed if you were to draw a “Circle” inside of the bones of the Pelvis and Sacrum
What is demarcated by the Pelvic Inlet?
The plane of the Pelvic Inlet separates the False Pelvis and Abdomen (Superior) from the True Pelvic Cavity (Inferior)
What is the Pelvic Brim?
This is the “Circle” around the bones that indicates the Pelvic Inlet using:
- Sacral Promontory (Top of S1)
- Ala (wings) of Sacrum
- Linea Terminalis of the Pelvis
Female Pelvis Characteristics
- Wider Pubic Angle (80º-85º like making an L with your index and thumb)
- Rounder Pelvic Inlet
Male Pelvis Characteristics
- Smaller Pubic Angle (50º-60º like making a peace sign)
2. Heart/Oval shaped Pelvic Inlet
False Pelvis (Greater Pelvis)
- Larger Pelvic Are
- Area Superior to the plane of the Pelvic Inlet that is still is surrounded by the wings of the Ilium
- in ABDOMINAL CAVITY
- Contains Digestive Organs
What is the Linea Terminalis?
Ridge on the Pelvic bones that forms the outline of the Pelvic Inlet
True Pelvis (Lesser Pelvis)
- Smaller Pelvis area
- Area Inferior to the plane of the Pelvic Inlet
- in Pelvic Cavity
- Contains Pelvic Outlet
Pelvic Outlet
- Inferior border of the Pelvic Cavity
- Plane formed by ligaments and muscles
- Open aside from the barrier formed by the muscles of the Pelvic Floor
What does the Pelvic Floor do?
- Separates the Pelvic Cavity from Perineum and covers the Pelvic outlet
- Synonymous with Pelvic Diaphragm Muscles
- Bowl shaped
What are the boundaries of the True Pelvis?
- Pelvic Inlet (Superior)
- Pelvic Wall (Circumferential)
- Pelvic Outlet (Inferior)
What makes up the Pelvic Wall and provides the Circumferential/Lateral boundaries of the Pelvis?
- Obturator Internus Muscle (Lateral)
- Piriformis Muscle (Lateral)
- Sacrotuberous Ligament
- Sacrospinous Ligament
What is the Sacrotuberous Ligament?
A very strong supportive ligament that attaches the Sacrum to the Ischial Tuberosity
What is the Sacrospinous Ligament?
A ligament that runs perpendicular to the Sacrotuberous ligament attaching the Sacrum to the Ischial Spine
The perpendicular way that the Sacrotuberous and Sacrospinous Ligaments causes the formation of
- Greater Sciatic Foramen
- Lesser Sciatic Foramen
FROM the Greater and Lesser Sciatic Notches
How does the Piriformis Muscle pass from the Pelvic region to the Gluteal region?
Passes through Greater Sciatic Foramen
How does the Obturator Internus Muscle pass from the Pelvic region to the Gluteal region?
Passes through Lesser Sciatic Foramen
What are the boundaries of the Pelvic Outlet?
- Pubic Symphysis (Anteriorly)
- Inferior Pubic Ramus (Anteriorly)
- Ischial Tuberosities (Laterally)
- Sacrotuberous Ligament (Posteriorly)
- Coccyx (Posteriorly)
Lithotomy Position
Patient laying on their back with legs up like birthing position
What are the Pelvic Diaphragm Muscles (Pelvic floor muscles)?
- Levator Ani (bigger)
2. Coccygeus
What is the Levator Ani?
- Largest of the Pelvic Diaphragm Muscles
2. Sling-like muscle with multiple parts called Kegels
Where are the origin and insertion of the Levator Ani?
Origin: Coccyx
Insertion: Pubic Bone
What openings are in the Levator Ani?
- Anal Aperture (Anal Canal)
2. Urogenital Hiatus (Vagina)
What is the Coccygeus?
Smaller Pelvic Diaphragm Muscle that originates at the Ischial Spine and inserts on the Lateral Coccyx
What are the functions of the Pelvic Diaphragm Muscles?
- Supporting and keeping Pelvic Organs inside of the Pelvis
- Supporting Sphincters for passing through organs (Anus and Vagina)
- Rectal Flexion (keeps shape)
What Urinary Organs are in the Pelvic Cavity?
- Bladder
- Distal Ends of the Ureters
- Urethra
What Digestive Organs are in the Pelvic Cavity?
- Terminal end of Digestive Tract
- Rectum
- Anal Canal
What is the Perineum?
Anything Inferior and Superficial to the Pelvic Floor:
- External Genitalia
- Opening of Urinary, Digestive, and Reproductive Tracts
What is the Rectum?
Most posterior structure of the Pelvis that can expand to store feces
Rectum is a continuation of the…
Sigmoid Colon
Where is the Rectum?
Resting on the curve of the Sacrum in the Sigmoid Colon
Rectum terminates at the…
Anal Canal
What does the Anal Canal pass through?
Pelvic Floor Muscles of the Pelvic Diaphragm
Constriction of the Pelvic Floor Muscles does what to the Anal Canal?
Constriction helps close off the Anal Canal to maintain continence
Pelvic Floor Muscles orientation with the Rectum causes what?
A Flexure Point (curve) in the Rectum that angles the Anal Canal
Opening from Anal Canal to the outside world is called the…
Anus
What are the sphincters of the Anal Canal?
- Internal Anal Sphincter (Smooth Muscle)
2. External Anal Sphincter (Skeletal Muscle)
What are the Parasympathetic and Sympathetic controls of the Internal Anal Canal?
- Paraympathetic relaxes Anal Canal muscles allowing defecation
- Sympathetic contracts Anal Canal muscles, NO defecation
Anal Canal goes through what muscle of the Pelvic Floor?
Levator Ani
What is the Pectinate Line?
Demarcation of the Digestive Tract that splits the Rectum in terms of Embryologic Division
What is superior to Pectinate line?
Parts of the Embryologic Hindgut
Why is the Pectinate Line important?
It signifies different:
- Lymph Drainage
- Blood Supply
- Embryonic Origin
- Associated Pathology
What supplies blood to the Rectum SUPERIOR to the Pectinate Line (Hindgut)?
Superior Rectal Artery
Where does blood go from the Rectum SUPERIOR to the Pectinate Line (Hindgut)?
Portal System (Liver) via the Portal Vein
Where does blood go from the Rectum INFERIOR to the Pectinate Line?
Caval System (IVC)
Name the sites of Portal-Systemic Anastomosis and why this is important
These are the places blood goes back to the IVC but does NOT enter the Hepatic Portal System (Liver):
- Esophagus
- Inferior Rectum/Anus
- Paraumbilical Are
What supplies blood to the Rectum INFERIOR to the Pectinate Line?
Middle and Inferior Rectal (Anal) Arteries
Where do Lymphatics go for parts of the Rectum SUPERIOR to the Pectinate Line (Hindgut)?
Internal Nodes
Where do Lymphatics go for parts of the Rectum INFERIOR to the Pectinate Line?
Superficial Nodes
Where does Autonomic Innervation of the Rectum SUPERIOR to the Pectinate Line (Hindgut)?
- Parasympathetic by Pelvic Splanchnic
2. Sympathetic by Lumbar Splanchnic
What provides Somatic (Skeletal) Innervation to the Rectum INFERIOR to the Pectinate Line?
Pudendal Nerve
What is the Bladder and where is it located?
Hollow Organ that serves as a reservoir for urine located most Anteriorly in the Pelvis
What is the Trigone?
A smooth walled triangular region at the base (back) of the Bladder between the 2 Ureters (entry) and the Urethra (exit)
What is the Embryological Origin of the Median Umbilical Ligament?
The Urachus which was a connection between the bladder and the Umbilical Cord in the Fetus
Describe the Superior Portion of the Bladder when empty and full
Empty- Flat and completely in the Pelvis
Full- Balloons upward into the Abdominal Cavity
The Apex of the Bladder points over the…
Pubic Symphysis
Where do the Testes develop in males?
Posterior Wall of the Abdominal Cavity
How do the Testes descend and what do they descend with?
They descend through the Inguinal Canal with:
- Nerves
- Vessels
- Lymphatics
- Vas Deferens
What are the Seminiferous Tubules?
Highly coiled vessels in the Testes that produce Sperm
What is the Epididymis?
A coiled tube on the posterior side of the Testes where sperm gain motility and are stored or sent to the Vas Deferens
Sperm Transport
“SEVN UP”
- Produced in Seminiferous Tubules
- Stored in Epididymis
- Vas Deferens
- Ejaculatory Duct
- Urethra
- Penis
What surrounds the Testes in the Scrotum?
- Tunica Albuginea (Capsule)
2. Tunica Vaginalis (anterior sac of Peritoneum
What do the Testes bring during descent through the Inguinal Canal from the Anterior Abdominal Wall?
- Vas Deferens (drains sperm)
- Venous Plexus (drains blood)
- Testicular Artery (supplies blood)
- Genitofemoral Nerve
- Cremaster Muscle
Where does the Cremaster Muscle come from?
Extension of the Internal Oblique
What does the Cremaster Muscle do?
It is around the Scrotum and Cord and controls the position of the Testes within the Scrotum
Why is the Ilioinguinal Nerve unique?
It is not present through entire Inguinal Canal
2. Sneaks in from the side and has some anterior sensory
What is the pathway of the Vas Deferens through the Pelvic Cavity?
- Exits Scrotum
- Travels through Inguinal Canal
- Enters Pelvic Cavity
- Travels behind the Bladder
- Joins Seminal Vesicles to become Ejaculatory Ducts
What is the Seminal Vesicle?
- 2 Bilateral Glands located Posteriorly to the Bladder that secrete Alkaline Seminal Fluid
- Joins Vas Deferens to form the Ejaculatory Ducts in Prostate
Where do the Ejaculatory Ducts join the MALE Urethra?
In the Prostate they join the Prostatic Urethra
What do you call the Sphincter at the base of the Bladder and start of the MALE Urethra?
Internal Urethral Sphincter
Why CAN’T Urination and Ejaculation occur simultaneously?
The Internal Urethral Sphincter is located at the base of the bladder and when it is Sympathetically Activate, the muscles contract which closes the sphincter
How does the Vas Deferens cross over the Ureter in the Pelvic Cavity?
“Water Under the Bridge”
Ureter with Water passes under the Vas Deferens
The Perineum is…
Everything INFERIOR and SUPERFICIAL to the Pelvic Cavity
What is the function of the MALE Bulbourethral (Cowper’s) Glands?
Secrete Lubricant and Pre-Ejaculate into Penile Urethra
Where are the MALE Bulbourethral (Cowper’s) Glands located?
Underneath the prostate in the Deep Pouch of the Perineum
What are the FEMALE Reproductive Organs located in the Pelvic Cavity?
- Ovaries
- Uterine/Fallopian Tubes
- Uterus
Where is the embryological origin of the Ovaries?
Abdominal Cavity before they descend to the Lateral Pelvis
Is there a connection between the Peritoneal Cavity and the Reproductive system in men and women?
Men- NO
Women- Yes, the Fallopian Tube
Describe the relationship between the Ovary and the Fallopian Tube
NOT attached, but the Fimbriae sweep the eggs into the Fallopian Tube
What action does the Ovary perform?
- Produce the Ovum (egg) and release it into the peritoneal cavity
- In close contact with but not attached to the Fallopian Tube
What is the Ovarian Ligament?
- Attaches the Ovaries to the Uterus
2. Caused the descent of Ovaries from the Abdomen to the Pelvis in the Embryo
What are the parts of the Fallopian (Uterine) Tubes?
- Infundibulum
- Ampulla
- Isthmus
What is the Infundibulum?
Wide portion of the Fallopian Tube with Fimbriae that sweep the Ovum into the Fallopian Tube
What is the Ampulla?
The narrow middle portion of the Fallopian Tube where the egg is fertilized by sperm
What is the Isthmus?
The narrowest part at the end of the Fallopian Tube connected to the Uterus
What structures connects the Uterus to the Labia Majora?
Round Ligament
What structure guides the descent of the Male Testes into the Scrotum?
Gubernaculum
What structure in Male and Female reproductive systems are embryologically equivalent and came from the same precursor tissue?
Scrotum in Males
Labia Majora in Females
What is the Round Ligament?
- Connects Uterus to the Labia Majora
2. Runs through the Inguinal Canal
What structure goes through the Inguinal Canal in Males?
Spermatic Cord
What are the 3 areas of the Uterus?
- Fundus
- Body
- Cervix
What is the Uterus?
Muscular Hollow structure located between the Bladder and Rectum
What are the parts of the Cervix called?
- Internal Os (faces the Uterus)
- Cervical Canal
- External Os (faces the Vagina)
What are the 3 areas of the Uterine Wall called? (Superficial to Deep)
- Perimetrium
- Myometrium
- Endometrium
In females, what is the Perimetrium?
- Outermost Uterine Wall layer
2. Serous Membrane covering that comes from the Peritoneum
In females, what is the Myometrium?
- Middle layer of the Uterine Wall
- Thick layer of Smooth Muscle
- Contracts during menstrual cycle and birth
In females, what is the Endometrium?
- Innermost layer of the Uterine Wall
2. Responds to hormonal activity
What is the position of the Uterus?
Anteverted (Tipped forward) and it sits on top of the Bladder
How does the Vaginal Canal travel in reference to the Urethra?
Vaginal Canal travels POSTERIORLY to the Urethra
How is the Vaginal Canal angled?
Posteriorly
What is Effacement?
When the Cervix dilates and thins out during childbirth making the Internal and External Os become one
What is the point of a Speculum Exam?
Using the Vaginal Canal to observe the External Os of the Cervix
How can you remember the angles of the Uterus, the Cervix, and the Vaginal Canal?
The 3 axes of the Uterus, Cervix, and Vaginal Canal make an “A” around the Bladder
What is the Introitus?
External opening of the Vaginal Canal posterior to the Urethral Opening
What is the pathway of the Vaginal Canal?
- Vaginal Canal travels through the Pelvic Floor into the Perinum
- Posterior to the Urethra and Bladder
- Anterior to the Rectum
What is the Vaginal Vault?
The junction where the wider Internal End of the Vagina meets the narrower External Cervix
What are the Internal Vaginal Fornix and the External Vaginal Fornix?
Recesses (pockets) around the External Cervix at the Vaginal Vault due to the Internal Vagina being wider
Describe the Abdominal Peritoneum and how it relates to the Pelvis
Peritoneum that covers the organs of the Abdominal Cavity drapes down into the Pelvis and covers the tops of the Pelvic organs
What Pelvic Organs does the Abdominal Peritoneum drape onto?
- Anterior Portion of Superior Rectum
- Top of Uterus
- Top of the Bladder
What are the names of the Pouches in the FEMALE Pelvis that are outlined by Abdominal Peritoneum?
- Rectouterine Pouch (larger)
2. Vesicouterine Pouch
What is the Rectouterine Pouch in Females?
- AKA Pouch of Douglas
2. Space Posterior to Uterus and Anterior to the Rectum outlined by the Peritoneum
What is the Vesicouterine Pouch?
Space Posterior to Bladder and Anterior to the Uterus outlined by the Peritoneum
When a FEMALE is UPRIGHT, what is the most INFERIOR space in the Abdomino-Pelvic Cavity?
Rectouterine Pouch
What is the name of the Pouch in the MALE Pelvis that is outlined by Abdominal Peritoneum?
Rectovesical Pouch
What are the FEMALE Peritoneal Ligaments?
- Broad Ligament
- Suspensory Ligament of the Ovary
- Ovarian Ligament
- Cardinal Ligament
What is the Broad Ligament?
Main ligament formed by the draping of the Abdominal Peritoneum over the top and sides of the Uterus, Fallopian Tubes, and Ovaries
What is the Mesometrium?
- The part of the Broad Ligament that is in contact with the Uterus
- Same as the Perimetrium
What is the Mesosalpinx?
- The part of the Broad Ligament that is in contact with the Fallopian Tubes
- Folds of Peritoneum
What is the Mesovarium?
- The part of the Broad Ligament that is in contact with the Ovaries
- Folds of Peritoneum
What is the Suspensory Ligament of the Ovary?
Folds of Peritoneum that contain the Ovarian Blood Vessels coming from the Abdominal Wall
What is the Cardinal Ligament (Transverse Cervical Ligament)?
- Layer of Fascia that supports the Cervix by connecting it to the Lateral Walls of the Pelvis
- Contains Uterine Artery and Vein
Which Female Peritoneal Ligaments are formed by the folding of Peritoneum?
- Broad Ligament
2. Suspensory Ligament
Nothing in the Pelvic Cavity has…
Somatic Innervation because they are all Visceral organs
What kind of Innervation do the Pelvic Floor Muscles have?
Somatic Innervation
What kind of Innervation to the structures of the Perineum have?
Somatic Innervation
What is the major Somatic Nerve to the Perineal Structures?
Pudendal Nerve
What Plexuses travel through the Posterior Lateral Wall of the Pelvic Cavity to innervate the muscles that move the lower limb?
Lumbar, Sacral, and Coccygeal Plexuses
What do the Sacral Splanchnic Nerves do?
Innervate Visceral Organs and the Perineum
What are Pelvic Plexuses?
The way that Visceral Innervation is organized to carry Autonomic innervation
- Inferior Hypogastric Plexus
- Subplexus
What is the main branch that supplies blood to the Pelvis?
Internal Iliac Artery
What are the divisions of the Internal Iliac Artery?
- Anterior Trunk
2. Posterior Trunk
What structures get their blood supply from the Anterior Trunk?
- Pelvic Viscera
- Perineum
- Gluteal Region
- Inner Thigh
What structures get their blood supply from the Posterior Trunk?
- Pelvic Wall
2. Gluteal Region
What are the branches of the Anterior Trunk in the Pelvic Cavity?
- Umbilical Artery
- Inferior Vesicular Artery (Male) or Vaginal Artery (Females)
- Middle Rectal Artery
- Obturator Artery
- Internal Pudendal Artery
- Inferior Gluteal Artery
- Uterine Artery (Females)
What is the Umbilical Artery?
- Gives rise to the Superior Vesicular Artery (goes to Bladder)
- Important to the Fetus but not the adult
- Gives rise to the Medial Umbilical Ligament
What is the Medial Umbilical Ligament?
Remnant of the Umbilical Artery that travels up to the belly button
What does the Superior Vesicular Artery supply blood to?
Bladder
What does the Inferior Vesicular Artery (Males) supply blood to?
- Bladder
- Seminal Vesicle
- Prostate
What does the Vaginal Artery supply blood to?
- Bottom of the bladder
2. Vagina
What arteries provide blood to the Rectum?
- Medial Rectal Artery (AT)
2. Superior Rectal Artery (IMA)
What is the Internal Pudendal Artery?
Major Artery of the Perineum
Which artery is larger in pregnant females opposed to non-pregnant?
Uterine Artery
Where do the Gonadal Arteries come from?
Abdominal Aorta
Describe pathway of the Testicular Arteries
Branches off of the Abdominal Aorta and travels through the Inguinal Canal in the Spermatic Cord
Describe the pathway of the Ovarian Arteries
Branches off of the Abdominal Aorta into the pelvis traveling with the Suspensory Ligament of the Ovary
Right Gonadal Vein drains…
Directly into the IVC
Left Gonadal Vein drains…
Into the Left Renal Vein
Where do the Pelvic Lymphatics drain?
- Superficial and Deep Inguinal Nodes
- Internal and External Iliac Nodes
- Abdominal Nodes
Where does Gonadal Lymphatic Drainage go?
Abdominal Nodes
Where does the Lymphatic Drainage of structures of the Perineum such as skin go?
Superficial Inguinal Nodes
Where does the Lymphatic Drainage of structures inside of the Pelvis go?
Internal (mostly) and External Iliac Nodes