Pelvis and Perineum Problem Set (Answer Key)
Identify the typical arterial supply of the pelvis and perineum in the drawing.
1 abdominal aorta 2 gonadal 3 inf mesenteric 4 common iliac 5 median sacral 6 internal iliac 7 external iliac 8 femoral 9 iliolumbar 10 lateral superior sacral 11 lateral inferior sacral 12 sup. Gluteal 13 sup rectal 14 umbilical 15 obturator 16 inferior vesical 17 middle rectal 18 internal pudendal 19 inferior gluteal
Identify the typical venous supply of the pelvis and perineum in the drawing.
1 inf vena cava 2 left renal 3 right renal 4 hepatic portal 5 left gonadal 6 right gonadal 7 Common iliac 8 internal iliac 9 external iliac 10 obturator 11 sup. Vesical/uterine 12 inf. Vesical vaginal 13 middle rectal 14 internal pudendal 15 sup. rectal
List the functions of the pelvic girdle.
1)bear the weight of the upper body when sitting and standing 2) transfer that weight from the axial to the lower appendicular skeleton for standing and walking and 3) provide attachment for the powerful muscles of locomotion and posture and those of the abdominal wall, withstanding the forces generated by their actions. 4) contain and protect the pelvic viscera (e.g. parts of the urinary reproductive and digestive systems), 5) provide support of the abdominopelvic viscera and gravid uterus, 6) provide attachment for the erectile bodies of the external genitalia, and 7) provide attachment for the muscles and membranes that assist the functions listed above by forming the pelvic floor and filling gaps that exist around it.
What two types of joint are associated with the anterior and posterior sacroiliac joint?
Anterior - synovial Posterior - syndesmosis
This is the location of somas (cell bodies) that initiate and interrupt micturition
Anterior gray column of the second, third, and fourth sacral segments of the spinal cord
Bordered by the: Midline raphe from the perineal body to coccyx and anococcygeal ligament, posterior border of the urogenital diaphragm, inferior border of gluteus maximus
Base of ischiorectal fossa
With what fascia is the external perineal fascia continuous?
Buck's fascia of penis and muscular fascia of external oblique m.
This is the location of neuron somas (cell bodies) that are activated by stretch of the urinary bladder detrusor muscle fibers
Dorsal root ganglia of S2, S3, S4
What route is taken by the blood and urine which escapes in a traumatic injury to the male urethra
Extravasating blood and urine escape into the superficial perineal cleft, then pass into the scrotum deep to the dartos muscle and into the penis superficial to Buck's fascia. Also the anterior abdominal wall deep to Scarpa's fascia
What region of the pelvis is superior to the linea terminalis and sacral promontory, chiefly characterized by the iliac fossae?
False or greater pelvis
This is the location of neuron somas (cell bodies) that innervate the smooth muscle to cause contraction of the urinary bladder
Ganglia of the outer and submucosa of the urinary bladder (parasympathetic terminal ganglia).
This is the location of neuron somas (cell bodies) that innervate blood vessels in the wall of the urinary bladder
Ganglia of the pelvic portion of the sympathetic ganglia of the pelvic plexus (collateral ganglia).
What two foramen does the pudendal nerve pass through?
Greater sciatic foramen and lesser sciatic foramen
where do the tendons of the obterator internus and piriformis muscles have their distal attachment?
Greater trochanter of femur
List the osseofascial boundaries of the superficial perineal compartment.
Ischiopubic rami to the external perineal fascia, and perineal membrane.
To what structures is Colle's fascia attached?
Ischiopubic rami, to the external perineal fascia of the posterior border of the urogenital triangle, to the perineal membrane, to the deep transversus perineal muscle.
What are the muscles innervated by the motor component of the pudendal nerve?
Levator ani External anal sphincter External urethral sphincter Superficial and deep transverse perineus muscles Bulbospongiosus muscle Ischiocavernosus muscle
Bordered by the: line between the ischial tuberosities, coccyx, bilateral lines between the coccyx and ischial tuberosities
Perineum
______ refers both to the area of the surface of the trunk between the thighs and the buttocks, extending from the coccyx to the pubis, and to the shallow compartment lying deep (superior) to this area but inferior to the pelvic diaphragm. Contains the anus and external genitalia.
Perineum
Identify the three bones that compose the adult pelvic girdle
Right and left hip (coxal) bones which are composed of ilium, ischium and pubis, and sacrum
What are the spinal root origins of the pudendal nerve?
S2, S3, S4
What spinal roots form the pudendal nerve?
S2-S4
What is the sensory and motor distribution of the pudendal nerve?
Sensory: Peri-anal skin Skin of posterior scrotum/labium majus Skin of labium minus Skin of penis/clitoris Motor: Levator ani External anal sphincter External urethral sphincter Superficial and deep transverse perineus muscles Bulbospongiosus muscle Ischiocavernosus muscle
Contrast the terms spondylolysis and spondylolisthesis
Spondylolysis is a fracture of the pars interarticularis. Sponylolisthesis is bilateral fracture of the pars interarticularis and anterior displacement of the affected vertebra.
What fascia fills the ischiorectal fossae?
The adipose layer or Camper's fascial layer
Bordered by the: line between the ischial tuberosities, coccyx, bilateral lines between the coccyx and ischial tuberosities
The anal triangle
Bordered by the: Pubic symphasis, ischiopubic rami, and line between the ischial tuberosity
Urogenital triangle
What three muscles listed in the unit 3 muscle table from lab compose the levator ani and help form the pelvic floor? What other muscle helps from the pelvic floor?
[see lab table]
Name the three muscles of the superficial perineal compartment.
bulbospongiosus m., ischiocavernosus m. and superficial transverse perineus m.
What are the subdivisions of the uterine tube?
fimbriated end, infundibulum, ampulla, isthmus, intramural or uterine part.
Identify the three main parts of the uterus?
fundus, body, cervix
What is defined by the following description: superior to the pelvic inlet. bounded by the iliac alae posterolaterally and the anterosuperior aspect of the S1 vertebra posteriorly. occupied by abdominal viscera (e.g., the ileum and sigmoid colon)
greater pelvis
What is the male counterpart of each of the following female anatomy? round ligament of the ovary
gubernaculum
In terms of muscle, what is the difference between the internal anal sphincter and external anal sphincter?
internal anal sphincter - smooth muscle; external anal sphincter - skeletal muscle
What three ligaments pull the ilia medially to compress the sacrum between them?
interosseous ligaments, posterior sacro-iliac ligaments and iliolumbar ligaments
What ligaments transfers the weight of the upper body from the axial skeleton to the two ilia?
interosseous sacroiliac ligaments
What remains of the umbilical artery after birth?
it becomes the medial umbilical ligament
What is the relationship of the ovarian artery to the ureter at the pelvic brim?
it is lateral to the ureter
What muscle form the lateral and posterior wall of the true pelvis?
lateral—obterator internus m.posterior—piriformis m.
What is defined by the following description: between the pelvic inlet and pelvic outlet. bounded by the pelvic surfaces of the hip bones, sacrum, and coccyx. that includes the true pelvic cavity and the deep parts of the perineum (perineal compartment), specifically the ischio-anal fossae. that is of major obstetrical and gynecological significance
lesser pelvis
What portion of the male urethra is most prone to traumatic injury?
membranous urethra
Identify the two main layers of tissue that make up the wall of the uterus?
myometrium and endometrium
What muscle helps from the lateral pelvic wall?
obturator internus m.
Lateral extensions on each side of the rectum of the "pocket" (rectouterine pouch) are the ________
pararectal fossa
What is formed by the following: promontory and ala of the sacrum (superior surface of its lateral part, adjacent to the body of the sacrum). a right and left linea terminalis (terminal line) together form a continuous oblique ridge consisting of the: arcuate line on the inner surface of the ilium. pecten pubis (pectineal line) and pubic crest, forming the superior border of the superior ramus and body of the pubis
pelvic brim, which also defines the pelvic inlet
What is bound by the following description: pubic arch anteriorly. ischial tuberosities laterally. inferior margin of the sacrotuberous ligament (running between the coccyx and the ischial tuberosity) posterolaterally. tip of the coccyx posteriorly
pelvic outlet
What muscle helps form the posterior pelvic wall?
piriformis m.
The peritoneum passes over the fundus of the uterus and descends the entire posterior aspect of the uterus onto the posterior vaginal wall before reflecting superiorly onto the anterior wall of the inferior rectum (rectal ampulla). The "pocket" thus formed between the uterus and the rectum is the _________
rectouterine pouch
What is the male counterpart of each of the following female anatomy? pudendal cleft
scrotal raphe
What is the male counterpart of each of the following female anatomy? labia majora
scrotum with dartus muscle
What type of joint and what type of cartilage forms the pubic symphysis?
secondary cartilaginous joint; fibrocartilage
What are the sources of motor and sensory innervation of the dartos muscle?
sensory - genital branch of genitofemoral n., ilioinguinal n., perineal branch of posterior femoral cutaneous n. and posterior scrotal branch of pudendal n. Motor - postganglionic sympathetic nerve fibers of genital branch of genitofemoral n. and posterior scrotal n.
What is the relationship of the uterine artery to the ureter in the base of the broad ligament?
the artery is anterior to the ureter
What is the anterior gap between the medial borders of the levator ani muscles of each side—that gives passage to the urethra and, in females, the vagina?
urogenital hiatus