The Pelvis Flashcards
1
Q
What is the superior border of the pelvis?
A
The iliac crests of the pelvic bones.
2
Q
What forms the inferior border of the pelvis?
A
The pelvic diaphragm.
3
Q
What forms the anterior boundary of the pelvis?
A
The symphysis pubis
4
Q
What structures mark the posterior boundary of the pelvis?
A
- Lumbar spine
- Sacrum
- Coccyx
5
Q
Describe the shape of the pelvic cavity?
A
Basin shaped bound by skeletal framework
6
Q
What is the inferior portion of the abdominopelvic cavity?
A
The pelvic cavity
7
Q
What lines the pelvic cavity?
A
Partially lined by peritoneum of the abdominal cavity that drapes over the pelvic viscera.
8
Q
What does the pelvic cavity contain?
A
- Reproductive organs
- Urinary bladder
- Rectum
9
Q
How many regions is the pelvis divided into? What are they?
A
Two.
1) True pelvis
2) False pelvis
10
Q
What forms the pelvic brim?
A
Bony features of the pelvis (oblique plane connecting the symphysis pubis and the sacrum).
11
Q
What does the pelvic brim do?
A
It defines the boundary between the true and false pelvis and marks the pelvis inlet of the pelvis.
12
Q
What are the other names for the “true pelvis”?
A
1) Lesser pelvis
2) Birth canal (in women)
13
Q
Where is the true pelvis located?
A
Inferior to the pelvic brim
14
Q
What two things is the true pelvis found between?
A
The pelvic inlet and the pelvic outlet
15
Q
What structures enclose the true pelvis?
A
Sacrum
Ischium
Pubis
Pelvic portion of the ilium
16
Q
What structures/organs does the true pelvis contain?
A
Bladder
Rectum
Prostate (In men)
Reproductive organs
17
Q
What is the pelvic outlet?
A
It is the inferior opening (exit) of the true pelvis
18
Q
What is another name for the “false pelvis”?
A
The greater pelvis
19
Q
Where is the false pelvis located?
A
It is the area superior to the pelvic brim
20
Q
What two things is the false pelvis located between?
A
The iliac fossae and pelvic rim
21
Q
What cavity is the false pelvis considered a part of?
A
The abdominal cavity
22
Q
What does the false pelvis contain?
A
Abdominal viscera
Parts of the small intestine and sigmoid colon
Bladder (when full)
Uterus/fetus in the 2nd and 3rd term
23
Q
What are the regions of the pelvis?
A
Three subdivisions
1) Right iliac
2) Hypogastrium
3) Left iliac
24
Q
Where is the right iliac region?
A
Right lower area of abdominopelvic cavity
25
What does the right iliac region contain?
Caecum
Appendix
Distal end of right ureter
Right ovary
26
Where is the hypogastrium located?
Midline and located between right and left iliac regions
27
What does the hypogastrium region contain?
Distal end of ileum
Urinary bladder
Uterus
28
Where is the left iliac region located?
Left lower area of the abdominopelvic cavity
29
What does the left iliac region contain?
Sigmoid colon
Left ovary
Distal end of left ureter
30
What is the "bony structure"?
Framework formed by the sacrym, coccyx and paired hipbones.
31
What is the purpose of the bony structure?
Support and transmit weight of body
Protect pelvic viscera
Birth canal in females
Muscle attachment
Attach legs to torso
32
What is the sacrum?
Triangular shaped bone composed of 5 fused vertebral segments
33
Where is the sacrum located?
Posterior midline portion of bony pelvis
34
What does S1 articulate with superiorly?
L5
35
What is the sacral promontory?
Located on S1 it is an anterior ridge that acts as a landmark for the posterior portion of the true pelvic inlet or brim
36
What does S5 articulate with?
Coccyx
37
What do the lateral masses of the sacrum articulate with?
The os coxae at the sacroiliac joints laterally
38
What is the coccyx?
Inferior portion of vertebral column or the "tailbone"
39
What does the coccyx consist of?
3-5 rudimentary vertebrae
40
What is the function of the coccyx?
Site of muscle attachment
41
What are the other names for the "hipbones"?
Os Coxae
Innominate
42
What are the hipbones?
3 bones fuse at puberty to form one unit (ilium, pubis, ischium)
43
What is the ilium?
The largest and most superior portion of the hipbones.
44
What is the Ala?
The large, flaring superior surface of the ilium
45
What is the iliac fossa?
Part of the ilium, it is the inner aspect of ala and upper basin of pelvic girdle
46
What is the iliac fossa covered with?
Iliacus muscle
47
What is the iliac crest?
Part of the ilium, it's the most superior portion of hip bone and the palpable upper surface of pelvis
48
What is the SI joint?
The articulation between ilium and sacrum posteriorly
49
What is a rami?
A branch/arm of bone
50
What does the pubis consist of?
A body and a superior rami and an inferior rami
51
Describe the superior ramus
Bone extending laterally from the body to connect with the ilium
52
Describe the inferior ramus
Bone extending inferiorly to meet the ischium
53
When the pubis rami meet what do they form?
The symphysis pubis
54
Where do the pubis rami meet?
Anterior midline
55
What is the obturator foramina?
Large opening formed by the junction of the pubic rami and ischium
56
Describe the ischium
Extends from ilium and connects with the pubic rami anteriorly
57
What is the position of the ischium?
Located inferior and posterior, extending from ilium and connecting with the pubic rami anteriorly
58
What is the ischial tuberosity?
A rounded, bulky bone prominence that is located inferior and posterior, supports body in seated position.
59
Where do the ilium, pubis and ischium meet?
In the acetabulum
60
What is the acetabulum?
The deep socket on the lateral aspect of the hip bone that fits the head of the femur
61
What meets at the acetabulum?
- ilium
- pubis
- ischium
62
What do the pelvic muscles do?
Assist in movement and stabilize and protect the pelvic structure
63
What is the psoas muscle?
Long muscle located lateral to the vertebral bodies extending from upper abdomen to pelvis
64
What is the iliacus?
Triangular shaped muscle that extends from the iliac crest of ilium and sacrum and lines each iliac fossa
65
The psoas muscle joins the iliacus muscle in the pelvis to form what?
Iliopsoas muscle
66
What is the iliopsoas muscle?
Powerful flexor muscle of the thigh
67
Where is the iliopsoas muscle located?
Travels anteriorly over the pelvic brim and inserts into the lesser trochanter of femur
68
What muscle aids in the lateral rotation of the thigh?
The obturator
69
How is the obturator muscle divided?
Internal and external parts
70
Where is the obturator muscle located?
Originates from the obturator foramen and attaches into the greater trochanter of femur
71
What is the piriformis?
Triangular shaped muscle that makes up a large part of the posterolateral wall of the pelvic cavity
72
Where is the piriformis located?
Originates on the anterior surface of sacrum and inserts into the greater trochanter of femur
73
What muscle is responsible for lateral rotation and abduction of flexed hip
Piriformis
74
What is the principle structure supporting the pelvic content?
Pelvic diaphragm
75
What is the pelvic diaphragm?
Hammock-like muscular structure that forms the pelvic floor
76
What are the main muscles of the pelvic diaphragm?
Levator ani and coccygeus
77
What is the largest and most important muscle in the diaphragm?
The levator ani
78
How many levator ani muscles are there?
Two
79
Where are the levator ani muscles located?
Two muscles originate from the pelvic wall of the pubis and the fibers converge to insert into the coccyx and muscles of the opposite side
80
What are the names of the levator ani muscles?
Pubococcygeus and iliococcygeus
81
The function of what muscles greatly effects the integrity of the pelvic floor?
Levator ani
82
What effects the integrity of the pelvic floor?
The levator ani muscles
They can weaken with age and childbirth causing prolapse and incontinence.
83
What is the smallest diaphragm muscle?
Coccygeus
84
What are the coccygeus?
Two smaller muscles that help make up the diaphragm.
They form the posterior aspect of the pelvic floor, they are a triangular sheet fanning out to insert on the sacrum and coccyx.
85
Where do the coccygeus originate?
The spine of the ischium
86
Why is it important to know about the potential spaces in the abdomen?
In the presence of pathology free fluid can accumulate.
87
What are the 3 potential spaces that exist in the female pelvis?
1) Anterior Cul de sac
2) Posterior Cul de sac
3) Space of Retzius
88
What is another name for the Anterior Cul de Sac?
Vesicouterine pouch
89
What is another name for the Posterior Cul de Sac?
Rectouterine pouch or pouch of douglas
90
What is another name for the Space of Retzius?
Retropubic or prevesicular space
91
What is the Anterior Cul de Sac?
The potential space between the bladder and uterus. Peritoneum drapes over the posterior bladder wall and anterior uterus, the space is usually empty but can contain loops of bowel.
92
What is the Posterior Cul de Sac?
The potential space between the uterus and the rectum. Peritoneum drapes over posterior uterus and anterior rectum.
93
What is the most "dependent" portion of the pelvis and what does this mean?
The Posterior Cul de Sac, means that it forms the most inferior part of the pelvis.
94
What is the space of retzius?
Small space between symphysis pubis and anterior bladder, it is filled with extraperitoneal fat.
95
What space is fluid most likely to accumulate in?
The Posterior Cul de Sac because it is the most inferior and gravity will cause the fluid to flow down and build up from there.
96
What are the 2 potential spaces in the male pelvis?
1) Posterior Cul de Sac
| 2) Space of Retzius
97
What are the other names for the Posterior Cul de Sac in the male pelvis?
Rectovesicular pouch or pouch of douglas
98
What is the Posterior Cul de Sac in males?
Space between the bladder and rectum.
99
What is the space of retzius in males?
Same as females
100
What are the functions of the female reproductive organs?
Produce sex hormones and ova, protect and support a developing embryo.
101
What is the uterus?
Hollow, pear shaped muscular organ that functions in menstruation, pregnancy and labor.
102
How many layers does the uterus wall have?
3
Endometrium, myometrium and perimetrium
103
What is the endometrium?
Most inner layer of uterus composed of epithelial and glandular cells, highly vascular and sheds with menstruation.
104
What is the myometrium?
The middle, muscular and most thick layer of the uterus, it is composed of muscle fibers that allow dramatic stretching of uterus during pregnancy.
105
What is the perimetrium?
Also known as the serosa, it is the outer layer of the uterus composed of serous peritoneum that covers the uterus and is continuous with the broad ligament.
106
What is the normal size of the uterus?
7-8cm in an adult
107
What factors vary the size of the uterus?
- Prepubertal
- Reproductive age
- Gravida/parity (pregnancy or not)
- Post-menoposal
- Disease
108
What is the most inferior region of the uterus?
The cervix
109
What is the cervix?
Cylindrical, inferior portion of uterus that extends from the isthmus into the upper vagina.
110
Can the cervix move?
No, it is fixed.
111
What is the endocervical canal?
2-3cm long canal inside the cervix consisting of the "internal os" (superior opening) and "external os" (inferior opening).
112
What is the narrowest section of the uterine body?
The isthmus
113
What is the isthmus?
Small, narrow portion of uterus directly superior to the cervix
114
What is the body of the uterus also know as?
The corpus
115
What is the body of the uterus?
Largest part of the uterus between the cervix and the fundus, it is somewhat mobile.
116
What is the cornua?
Lateral extensions of the uterus continuous with the fallopian tubes.
117
Where is a common place to have an ectopic pregnancy?
The cornua, serious problem because the uterus can rupture in this area.
118
What is the fundus?
Widest, rounded superior portion of the uterus that is superior to the insertion of the cornua/fallopean tubes.
"The hat" of the uterus.
119
Why do we need a full bladder for uterus UT?
The bladder pushes the uterus back to its full length as well as the bowel out of the way and provides a large anechoic window.
120
Where is the uterus in reference to the peritoneum?
Inferior
121
Where is the uterus in reference to the ovaries?
Medial
122
Where is the uterus in reference to the empty bladder?
Superior
123
What is the "normal" position of the uterus?
Tilts forward with a bend between cervix and body
124
What is anteverted?
Uterus tilts forward and forms a 90 degree angle to the cervix and vagina. (When the bladder is empty a normal uterus takes this postion).
125
What is antiflexed?
Uterine body is flexed anteriorly in the middle yet a 90 degree angle to the cervix is maintained.
126
What is retroverted?
Uterus tilts posterior and the cervix and vagina form a 180 degree angle (looks straight).
127
What is retroflexed?
Uterine body flexes at a sharp posterior angle but is 180 degrees (straight) with the cervix and vagina.
128
What is dextroversion?
A right lateral deviation (uterus leans to the right).
129
What is levoversion?
Left lateral deviation (uterus leans to the left).
130
Which uterus position is the most difficult to UT?
Retroflex because the uterus is deep in the body and it is difficult to penetrate.
131
What is the vagina?
Muscular tube extending from cervix to the external orifice and lying between the bladder (anterior) and the rectum (posterior).
132
What are the fornices?
Spaces in the upper vagina where it encircles the cervix.
133
What are the other names for the fallopian tubes?
Uterine tubes or oviducts
134
What are the fallopian tubes?
Paired muscular tubes that extend from the cornua of uterus and open into the peritoneum where the ovaries are located, they travel along the superior free margin of the broad ligament.
135
How long are the fallopian tubes?
10-12 cm in length
| 3 mm in width
136
What is the function of the fallopian tubes?
Location of fertilization.
Conducts ovum from ovary to uterus by peristalsis and also conducts sperm towards the ovum.
137
What are the segments of the fallopian tubes?
1) Interstitial/intramural
2) Isthmus
3) Ampulla
4) Infundibulum
138
What is another name for the interstitial segment of the fallopian tube?
Intramural
139
What is the interstitial segment of the fallopian tube?
Narrowest part of the tube located within the muscular wall of the uterus superiorly (cornua).
140
What is the isthmus segment of the fallopian tube?
A short, straight and narrow part of tube located immediately adjacent to the uterine wall laterally.
141
What is the ampulla segment of the fallopian tube?
The longest and most coiled section that widens laterally and it the most common site of fertilization.
142
What is the infundibulum segment of the fallopian tubes?
The funnel-shaped lateral portion of the tube where fimbria (finger like extensions) at end of tube help sweep ova towards the tube, located proximal to the ovary and opens into the peritoneal cavity.
143
What are the ovaries?
Bilateral, ellipsoid (oval) shaped structures that store the ova.
144
What do the ovaries produce?
Estrogen and progesterone
145
How big are the ovaries?
Normal adult:
3cm in length
2cm in width
AP (anterior/posterior) "depth" 1cm
Vary with age, menstrual phase and pregnancy.
146
Where are the ovaries located?
In the true pelvis, inside the adnexa, lateral to the uterus.
147
Where are the ovaries in reference to the broad ligament.
Posterior
148
Where are the ovaries in reference to the ureter?
Anterior
149
Where are the ovaries in reference to the internal iliac artery and gonadal vessels?
Anterior
150
What is found in the reproductive ovary?
Multiple anechoic follicles (normal).
151
What are the uterine arteries?
The uterine arteries branch off of the internal iliac arteries and travel superiorly along lateral aspect of uterus and then branch into smaller arteries (arcuate, radial and others) to supply the uterine layers and joins the ovarian artery at the level of the fallopian tubes.
152
Describe the venous vessels of the female pelvis?
Except for the left ovarian vein the venous vessels follow the arteries and assume the same name.
153
What are the ligaments in the female pelvis?
Folds of peritoneum that anchor and support the pelvic anatomy, the peritoneum extends laterally from the uterine surfaces to the lateral pelvic wall.
- Broad
- Round
- Ovarian
- Cervical
154
What are the broad ligaments?
Double fold of peritoneum that supports the uterus, encloses the oviducts and prevents side to side movement.
155
How do the broad ligaments divide the pelvis?
Into anterior and posterior compartments.
156
Are the broad ligaments true ligaments?
Not true ligaments, but act like them.
157
Where are the broad ligaments located?
Extend from anterior and posterior uterus to the lateral pelvic wall.
158
What are the round ligaments?
Ligaments extending from the lateral walls of uterus to the anterior pelvic wall, they are responsible for anterior tilt and stabilization of the fundus.
159
What are the ovarian ligaments?
Ligaments between the ovary and lateral uterus.
160
What are the cervical ligaments?
Extend from lateral cervix to pelvic floor, stabilizes the cervix and prevents downward displacement of uterus.
161
What is another name for the cervical ligaments?
Cardinal ligaments
162
What is the function of the male reproductive organs?
Producing sex hormones and contribute to male characteristics.
163
Where are the male reproductive organs located?
In the true pelvis and external on the body
164
What is the scrotum?
Saclike structure continuous with the abdominal wall
165
What does the scrotum contain?
The testes, epididymis, part of the ductus deferens
166
How is the scrotum divided and what divides it?
It is divided externally into lateral compartments by the median raphe.
167
What are other names for the median raphe?
Ridge or septum.
168
What are the muscles related to the scrotum and what is their purpose?
1) Dartos
2) Cremaster
They work together to elevate and lower the testicles to regulate the internal testicular temp and promote spermatogenesis.
169
What is the dartos?
Thin muscular layer that lies below the skin of the scrotum, it merges centrally to form the internal scrotal septum and divides the scrotum into 2 sacs that each contain a testis.
170
What is the cremaster?
Muscle that surrounds each testes, it arises from internal oblique muscles of the abdomen and lifts/lowers the testes.
171
What is the primary male reproductive organ and what does it produce?
The testes.
| Produces sperm and male sex hormones (testosterone)
172
Where do the testes arise from in a fetus?
The level of the kidneys and descend into scrotum after the 7th month.
173
What are the testes?
Ovoid paired glands suspended in the scrotal sac.
174
How large are the testes?
Maximum 5cm in length by 3cm in width and 3cm in AP (anterior/posterior "depth")
175
What is the tunica albuginea?
The dense outer capsule (testicular covering) adhering to both testes that has projections called septa.
176
What is the tunica vaginalis?
The thin outer layer (serous membrane) of the testes derived from peritoneum.
177
What are the two layers of the tunica vaginalis?
Visceral and parietal
178
What do the two layers of the tunica vaginalis do?
The visceral layer covers the testes
| The parietal layer lines the scrotum
179
What do the septa of the tunica albuginea do?
They converge posteriorly at mediastinum and divide each testes into lobules.
180
Describe the inside of the testes.
The parenchyma is divided into lobules which contain the seminiferous tubules.
181
How many lobules in each testes?
200-400
182
What are the seminiferous tubules?
Convoluted tubules contained in the lobules involved in sperm production.
183
How many seminiferous tubules are there?
1-3 per lobe
184
Where do the seminiferous tubules travel?
Converge towards the mediastinum and empty into the straight tubule towards the mediastinum and rete testis.
185
What is the straight tubule?
Short section of tube connecting the seminiferous tubules to the rete testes.
186
What are the mediastinum testes?
Wedge of connective tissue on the posterior aspect of testis that supports converging tubules.
187
What is the mediastinum testes continuous with?
The tunica albuginea and septa
188
What does the mediastinum testes enclose?
The rete testis
189
What is the rete testis
A network of ducts located in the mediastinum testis in the posterior aspect of the testis consisting of an inlet and an outlet.
190
What is the inlet of the rete testis?
Straight tubules
191
What is the outlet of the rete testis?
Efferent ductile
192
What are the efferent ducts?
Ducts exiting the rete testis and connecting to the ductus epididymis.
193
What are the ductus epididymis?
Tightly coiled tubes located on the posterior-lateral surface of each testis that are involved in the storage and maturation of sperm.
194
How long are the ductus epididymis?
6m long and 1mm in diameter
195
What are the ductus epididymis continuous with?
The ductus deferens (vas deferens).
196
How is the epididymis divided?
Head, body, tail
197
What is another name for the head of the epididymis?
Globus major
198
What is the head of the epididymis?
The largest portion, superior to the testes formed by the efferent ductules.
199
What is the body of the ductus epididymis?
Along posterolateral aspect of testes, ductus epididymus travels along the length of the body.
200
What is the tail of the epididymus?
Located at the inferior border of the testes the ductus epididymus travels along the length of the tail and empties into the ductus deferens within the spermatic cord.
201
What is another name for the tail of the epididymus?
Globus minor
202
What is another name for the ductus deferens?
Vas deferens
203
What is the ductus deferens?
A long tube originating from the tail of the epididymis.
204
Describe the proximal end of the ductus deferens?
It widens (ampulla) to meet the duct draining the seminal vesicle to form the ejaculatory duct.
205
Describe the path of the ductus deferens.
Ascends within the spermatic cord and travels through the inguinal canal to pelvis.
206
What is the spermatic cord?
Paired, tough outer covering that extends from testis to pelvis encasing numerous structures passing to and from the testes.
207
What structures does the spermatic cord include?
- Vas deferens
- Arteries and veins
- Lymphatics and nerves
208
What are the seminal vesicles?
Paired accessory glands, coiled tubes that form pouches (vesicles).
209
What do the seminal vesicles connect?
Each seminal vesicle duct joins the vas deferens to form the ejaculatory duct.
210
What do secretions of the seminal vesicles do?
Provide energy to the sperm.
211
Where are the seminal vesicles located?
Posterior and inferior aspect of the bladder.
212
Where are the seminal vesicles located in reference to the vas deferens?
Lateral
213
Where are the seminal vesicles located in reference to the prostate?
Superior
214
Where are the seminal vesicles located in reference to the rectum?
Anterior
215
What is the ejaculatory duct?
Extensions of the seminal vesicles, it directs seminal vesicle excretions to prostatic urethra
216
How does the ejaculatory duct travel?
Obliquely in the posterior aspect of the prostate.
217
What is the prostate composed of?
Fibromuscular and glandular tissue.
218
What is the prostate?
Conical shaped gland thats secretions aid in motility and fertility of sperm and move via several ducts to the urethra.
219
How big is the prostate gland?
3.5 cm in length
4 cm in width
2.5 cm in AP
220
What travels through the prostate gland?
1) Urethra travels centrally through prostate
| 2) Ejaculatory ducts descend inferiorly through the posterior portion of gland and open into prostatic urethra.
221
How is the prostate divided?
3 zones
| Peripheral, central, transitional
222
What is the peripheral zone?
Normally the largest zone of the prostate, the surgical capsule isolates it from other zones.
223
Where is the peripheral zone located?
Posterior and lateral to the distal prostatic urethra
224
What is the most common site of prostatic cancers?
The peripheral zone.
225
Where is the central zone of the prostate?
Extends from base of prostate to the verumontanum, located between the peripheral and transitional zones.
226
What is the verumontanum?
Junction of the central prostate with prostatic urethra.
227
What does the central zone surround?
The ejaculatory ducts
228
What is the transitional zone of the prostate?
Usually the smallest zone, lobes located on lateral aspect of the proximal urethra.
229
What is the base of the prostate?
Superior portion.
230
What is the base of the prostate in contact with?
The base of the bladder, lies adjacent to the neck of the bladder.
231
What is the apex of the prostate?
Inferior portion
232
What is the apex of the prostate in contact with?
The pelvic diaphragm.
233
Where is the prostate located in the body?
Midline and inferior to the base of the bladder.
234
Where is the prostate located in the body in reference to the pelvic diaphragm/floor?
Superior
235
Where is the prostate located in the body in reference to the rectum?
Anterior
236
Where is the prostate located in the body in reference to the symphysis pubis?
Posterior
237
What is the penis?
External reproductive organ.
238
What is the penis composed of?
3 cylindrical masses of erectile tissue and muscle.
1) Corpora cavernosa (2)
2) Corpus spongiosum (1)
239
What is the corpora cavernosa?
Dorsilateral location, becomes enlarges and filled with blood.
240
What is the corpus spongiosum?
Midventral location, encircles the spongy urethra and expands distally to form the glans penis.
241
Describe the blood supply/drainage of the testes.
The testicular artery originates off the aorta and supplies blood to the testes.
The right testicular vein drains into the IVC and left testicular vein drains into the left renal vein.
242
What supplies blood to the penis and urethra?
Internal pudendal arteries which are branches off the internal iliac arteries.
243
What drains the blood from the penis?
The superficial and deep dorsal veins which connect with the pudendal venous plexus.
