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TESTES, SCROTUM and
PROSTATE
The Scrotum, Testis, Epididymis
I. Introduction/ General Information
A. Scrotum
1. “Medial pendant pouch of loose
skin & superficial fascia” (Gray’s)
2. Raphe (Gr. “seam” or “suture”):
Superficial division
between compartments
3. Left side lower than right
Introduction, continued …
4. Dartos muscle (lies in fascia)
a. Temperature sensitive response
hot = relax
cold = contract
b. Right & left compartments
c. Testis, epididymis, tunica
vaginalis in each
Scrotum, Testes, Epididymis, con’t…
B. Testis
1. Suspended in scrotum by
spermatic cord
2. 4 - 5 cm long
3. Weigh 10.5 - 14 grams
3. Oval
Anatomy of the Male Pelvis
Testis, continued …
4. Descend from abdominal cavity
prior to birth
a. As they descend they collect
various coverings
b. Layers of abdominal wall
Scrotum, Testis, Epididymis, continued
…
C. Epididymis
1. Highly coiled tube
2. 15 - 16 feet long
3. Located on posterior & superior
margins of testes
4. Elongated, flattened structures
Epididymis, continued …
5. Partially covered by visceral
layer of the tunica vaginalis
6. Structurally divided into a head,
body, and tail
7. Tail is continuous with vas
deferens
8. Head receives efferent ductules
from testes
Testicular Anatomy
Testicular Anatomy, con’t…
D.
Appendages
1. Appendix of the testis
a. Lies beneath head of Epididymis
b. Remnant of the Mullerian duct
(gives rise to uterine tubes,
uterus in female)
c. May be referred to as “Hydatid
of Morgagni”
Testicular Anatomy, con’t…
Appendix of
Testis
Appendix of
Testis
Appendages, continued …
2.
Appendix of the Epididymis
a. Attached to head of Epididymis
b. Detatched, modified efferent
duct
c. Remnant of mesonephric duct
(primitive Epididymis, vas
deferens)
Appendages, continued …
Appendix of
Epididymis
Appendix of
Epididymis
II. Detailed Anatomy
A. Superficial inguinal rings
(of inguinal canal)
1. Triangular openings in
abdominal muscle
2. Superior & lateral to pubic
tubercles
3. House contents of spermatic
cord
Anatomy of the Spermatic Cord
Deep inguinal
ring
Superficial
inguinal ring
Detailed Anatomy, continued …
B. Scrotum
1. Layers, beginning superficially
a. Superficial fascia
1. skin & tunica dartos
b. Colle’s fascia
1. membranous layer of
superficial fascia
2. continuous over penis &
scrotum
Scrotum, continued …
c. External spermatic fascia: derived
from
1. transversus abdominis
2. internal oblique muscle
d. Cremasteric fascia: derived from
1. transversus abdominis
2. internal oblique muscle
e. Internal spermatic fascia: derived
from transversalis muscle
Detailed Anatomy, Layers of the Scrotum, continued …
Superficial (Dartos) Fascia
Colle’s Fascia
External Spermatic Fascia
Cremasteric Fascia
Internal Spermatic Fascia
Parietal Layer, Tunica Vaginalis
Visceral Layer, Tunica Vaginalis
Tunica Albuginea
Skin
Scrotum, continued …
f. Layers of peritoneum have serous
fluid between to allow mobility
1. Parietal layer of tunica vaginalis
a. Lines scrotal sacs
2. Visceral layer of tunica vaginalis
a. covers testis
b. part of epididymis
Scrotum, detailed anatomy, continued …
2. Testis (superficial to deep)
a.
b.
c.
d.
Visceral layer of tunica vaginalis
Tunica albuginea (capsule of testis)
Seminiferous tubules
Mediastinum testis (aka: hilum of
testis)
- Efferent Ductules
- Rete testis (network of tubules)
Testicular Anatomy (Netter, Plate 371)
Efferent Ductules
Rete Testis
Seminiferous Tubules
Mediastinum Testis
Tunica Albuginea
Detailed Anatomy, continued …
C. Spermatic Cord
1. Coverings from abdominal wall
2. Each spermatic cord contains:
a. Ductus (vas) deferens
b. Deferential artery & vein
c. Sympathetic nervous system fibers
Spermatic Cord, detailed anatomy, continued …
d. Spermatic/testicular artery & vein
e. Pampiniform plexus (network of
veins)
f. Lymph vessels
g. Vaginal ligament
1. Obliterated diverticulum
2. From Processus vaginalis (later)
Anatomy of the Spermatic Cord
III. Vessels & Nerves
A. Arteries
1. Testicular (internal spermatic)
artery
a. Branches directly from
abdominal aorta
b. Inferior to renal artery
c. Passes deep to peritoneum
Arteries, continued …
d. Travels through
inguinal canal
to reach testis
e. Testicular
migration
follows this
path
Testicular Artery
Arteries, continued …
2. Cremasteric artery
a. Branch of
Testicular Artery
b. Supplies Ureter
& Cremaster
muscle
Arteries, continued …
3. Perineal artery
a. Branch of internal
pudendal artery
b. Gives rise to posterior
scrotal artery
c. Supplies perineum &
external genitalia
Arteries, continued …
4. Superior Vesical artery
a. From fetal hypogastric artery
b. Gives rise to deferential artery
c. Anastomosis with testicular
artery
d. Supplies upper portion of
urinary bladder
Arteries of the Male Reproductive Tract

Fetal hypogastric
artery

Superior vesical
artery
Arteries of the Reproductive Tract
Vessels & Nerves, con’t …
B. Veins
1. Pampiniform plexus
(major venous drainage)
a. Approximately a dozen
b. form a network
c. Become larger,
converge approaching
inguinal canal.
Veins, continued …
2. Testicular vein
a. From
convergence of
pampiniform plexus
veins
b Enters IVC on right
c. Enters renal vein
on left
Vessels & nerves, continued …
C. Testicular Lymphatics
1. Follow arteries, veins
2. End in lumbar nodes
3. From scrotum, penis, prepuce:
terminate in superficial
inguinal nodes
4. From testis, spermatic cord:
drain into external iliac &
lumbar nodes
Vessels & Nerves, continued …
D. Nerves
1. Ilioinguinal nerve (L-1)
a. Into inguinal canal
b. Through superficial inguinal
ring
c. Supplies skin of upper
scrotum & medial thigh
d. via anterior scrotal nerve
Nerves, continued …
2. Genitofemoral nerve
a. Genital branch supplies
cremaster muscle
b. Receives branch of
iliohypogastric nerve
c. Femoral branch supplies
medial portion of thigh
d. Cremasteric reflex (scratch
medial thigh, causes
scrotum to contract)
IV. Embryology/Descent of Testis
A. Development
1. Scrotal swellings appear at ~ 7
weeks in lower abdominal wall
2. Processus Vaginalis:
a. evagination of peritoneum
b. push into scrotal swellings
3. Layers of abdominal muscle, fascia
4. Give rise to inguinal canal
Embryonic Development, continued …
4. Testes develop on posterior abdominal
wall
a. on urogenital ridge
b. near kidneys
5. Gubernaculum testis: ligament that
connects testis & epididymis to inside
of scrotum
Embryonic Development
Testis
Gubernaculum
Formation of Processus
Vaginalis
Development, continued …
6. As scrotum grows it pulls testes,
epididymis, and gubernaculum
posterior and inferior
7. Testis are retroperitoneal
a. travel inferiorly
b. exit through inguinal canal
c. into scrotum
Descent of Testes
Descent begins at
~3 months
Adult Configuration
Development, continued …
8. Gubernaculum testis becomes
scrotal ligament
9. Testis pulls spermatic cord along
10. Processus vaginalis pinches off
a. forms tunica vaginalis
b. Visceral: covers testis & epididymis
c. Parietal: folds back, leaves hilus
uncovered
Descent of Testes
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Descent of Testes, con’t….
B. Descent (by way of inguinal canal)
1. Inguinal ligament
a. Formed from exterior oblique
aponeurosis
b. Extends from anterior superior
iliac spine to pubic tubercle
c. Forms base of inguinal canal
d. Some fibers bend laterally &
posteriorly to form pectineal
ligament
e. Attached to bone
Descent, continued …
2. Deep inguinal ring (deep to anterior
superior iliac spine)
3. External spermatic fascia: derived
from what muscle??
4. Cremasteric fascia: formed from
what muscle??
Spermatic and Cremasteric Fasciae
Descent, continued …
5. Superficial inguinal ring
a. Subcutaneous opening of inguinal
canal
b. Surrounds contents & coverings
of spermatic cord
c. Located superior to inguinal
ligament & lateral to pubic
tubercle
Anatomy of the Spermatic Cord
Deep inguinal
ring
Superficial
inguinal ring
Descent, continued …
6. Testes develop in lumbar region
between peritoneum & fascia of
transversalis muscle
a. Begin descent at ~ 3rd month
b. Have descended from posterior
abdominal wall to deep inguinal
ring at ~ 7th month
Descent, continued …
c. Testes are preceded by Processus
Vaginalis (aka: peritoneal diverticulum)
d. Collect fascia, muscles: these give
rise to layers covering testes
e. Reach superficial inguinal ring by
~8th month
f. Testes are usually in scrotum by birth
Embryonic Development
Testis
Gubernaculum
Formation of Processus
Vaginalis
Descent of Testes
Fused
Processus
Vaginalis
Descent begins at
~3 months
Adult Configuration
V. Anomalies/Diseases
• Hernias
1. Indirect (oblique) inguinal hernia
a. Results when processus
vaginalis fails to close at birth
b. May allow for loops of small
bowel, greater omentum to
enter processus vaginalis &
scrotum
c. causing bowel obstruction
Hernias, continued …
2. Peritoneal cyst
a. Results from persistent connection
between peritoneal cavity & tunica
vaginalis
(due to partial closure of tunica vaginalis)
b. A cyst forms in the “connection”
space
c. May not be noticeable at birth;
later, accumulation of fluid may
form a Hydrocoele
Normal vs. Abnormal Scrotum
Note:
 Hydrocele

Testicular torsion

Normal Testis
Testicular Microlithiasis, Hydrocele
Hernias, continued …
3. Femoral hernia:
a. Opening in fascia covering
femoral canal
b. May allow small bowel to slide
through, causing obstruction
Hernias, continued …
4. Direct inguinal hernia
a. Arises from weakness in abdominal
wall near rectus abdominis muscle
b. Area is a common site of
herniation
c. Loops of small bowel may pass
through opening
Hernias, continued …
5. Congenital inguinal hernia
a. Result from failure of Processus
Vaginalis to close prior to birth
b. Allows head of Epididymis to
remain in deep inguinal ring
Anomalies of the Processus Vaginalis
Partially
Patent
Normal
Completely
Patent
Deep and
Superficial
Rings in
Infancy
Herniation
Anomalies/Diseases, continued …
B. Varicocoele
1. Expansion of pampiniform plexus
2. Usually seen on left (why??)
3. Can be palpated
a. feels like a “bag of worms”
Pampiniform Plexus
Anomalies/Diseases, continued …
C.
Cryptorchidism (occurs in 4% live births in U.S.)
1. Failure of testis to descend by birth
2. Unilateral = less potent;
Bilateral = sterile
3. Abdomen: sterile
4. Inguinal canal may contain testes
5. More often affected by malignancy
(20x)
6. Often descend in the first year of life
Anomalies/Diseases, continued …
D. Ectopic testis (out of place)
1. Migrated from normal course
2. Found in thigh or perineum
E. Hematocoele:
1. accumulation of blood
2. in tunica vaginalis from trauma
Anomalies/Diseases, continued …
G.
Lymph Edema
1.
2.
3.
4.
5.
Due to abdominal venous compression
Abdominal aortic aneurysm (AAA)
Intra-abdominal tumor
Cirrhosis with ascites
Filariasis
a. From filarial worms in drinking water
b. Can cause elephantiasis
Anomalies/Diseases, continued …
H. Testicular tumor
1. Generally have unknown etiology
2. Most arise from primordial germ cells
3. Usual symptom: scrotal mass of
increasing size
4. May be associated with pain
5. Any firm mass or cystic mass in
scrotum should be checked
Testicular Tumor: Doppler U/S
Testicular Tumor, continued …
6. Biopsy is primary diagnostic tool
a. Chest x-ray, IVP
b. To check for direct/indirect
metastasis
7. Treatment
a. Surgical excision if tumor is
benign
b. Castration with chemotherapy &
radiation if malignant
Endodermal Sinus and Yolk Sac Tumor
Doppler U/S
Tumor of Testis
PROSTATE GLAND
I. Introduction/General Information
A. Attached inferiorly to urinary bladder by
ligaments
B. Posterior to pubic symphysis
C. Surrounds superior portion of urethra
D. Anterior to rectum (palpation, ultrasound)
E. Conical shape
Introduction, Prostate Gland, continued …
F. Walnut sized
1. 4 cm trans x 2 cm A/P x 3 cm Sup/Inf
G. Lightly encapsulated
1. Fibrous connective tissue
2. Smooth muscle
3. Capsule extends into lobes
II. Prostate Gland: Detailed Anatomy
A. Largest male
accessory
gland
B. Located in
subperitoneal
compartment
(between pelvic
diaphragm &
peritoneum)
Prostate Gland, Mid-sagittal Section
Prostate Gland: Detailed Anatomy
C. Enclosed in fascial sheath
(aka: prostatic sheath)
1. Inferiorly, sheath is continuous
with superior fascia of
urogenital diaphragm
2. Posteriorly, sheath forms part of
retrovesical septum
Prostate Gland: Detailed Anatomy
D. Double Capsule
1. Fibrous portion contacts gland
2. External capsule formed by pelvic
fascia
3. Venous plexus lies between
Male Reproductive System, Posterior View
Detailed Anatomy, contined …
E. Conical shape with base (sup), apex (inf),
four surfaces
1. Surfaces: posterior, anterior, right &
left inferolateral
2. Base (aka: vesicular surface): superior
a. Attached to neck of urinary bladder
b. Prostatic urethra enters middle of
base close to anterior surface
Prostate Anatomy
Prostatic Urethra
Detailed Anatomy, contined …
3. Apex: inferior
a. Rests on superior fascia of urogenital
diaphragm muscle
b. Associated with sphincter urethrae
c. Contacts medial margins of levator ani
muscles
Detailed Anatomy, contined …
4. Posterior surface: triangular, flat
5. Anterior surface: narrow, convex
6. Inferiorolateral surfaces
a. Meet with anterior surface
b. Rest on levator ani fascia above
urogenital diaphragm
Detailed Anatomy, contined …
F. Lobes of the Prostate
1. Divisions are arbitrary, indistinct
2. Usually divided into
a. two lateral lobes
b. one median lobe
c. anterior and posterior lobes
Lobes of the Prostate, continued …
3. Median lobe
a. Lies posterior and superior to
prostatic utricle and ejaculatory
ducts
b. May project into urinary bladder
c. Utricle lies within lobe
1. Vestigial remains of uterine
homolog
2. Sometimes called “uterus
masculinis”
Lobes of the Prostate, continued …
4. Lateral lobes
a. Comprise the greatest mass of
the gland
b. Contain most secretory tissue
c. Are continuous posteriorly
5. Glandular tissue with varying amounts
of fibrous tissue
Lobes of the Prostate, continued …
Prostate Gland
in situ
Detailed Anatomy, continued
…
G. Blood & lymph
1. Arteries derived
from:
a. Internal pudendal
artery
b. Inferior vesical
artery
c. Middle rectal
artery
Blood & Lymph, continued
…
2. Veins
a. Form venous plexus
b. Drain into internal iliac veins
c. Communicate with vesical &
vertebral venous plexuses
Blood & Lymph, continued
…
3. Lymphatics
a. Most terminate in internal iliac &
sacral nodes (unable to palpate)
b. From posterior: to external iliac
nodes (unable to palpate)
Detailed Anatomy, contined …
H. Glandular tissue
1. 30 - 50 different glandular elements
a. Serous glands
b. 20 - 30 ducts empty into prostatic
urethra
2. Most are posterior & lateral to urethra
Blood & Lymph, continued
…
3. Prostatic secretions
a. Thin, milky, alkaline (looks like
skim milk)
b. Discharged at ejaculation
c. Make up ~ 1/3 of semen
Detailed Anatomy, continued …
I. Prostate size changes
1.
2.
3.
4.
5.
Small at birth
Enlarges at puberty
Maximum at about 13
Progressive enlargement after 40
Sometimes: undergoes atrophy
III. Pathology
A. Benign
prostatic
hypertrophy
(BPH):
1. Affects ~90%
of men >50
BPH, continued …
2. Common cause of urethral obstruction:
causes
a. Nocturia
b. Dysuria
c. Urgency
d. Back-pressure effects
e. Complete obstruction can occur
Pathology, continued …
B. Prostate cancer
1. Most common
cancer in males
Pathology, continued …
2. Metastasizes via blood (hematogenous)
or lymph (lymphogenous)
3. Common sites: vertebrae, pelvis
a. Via venous plexus surrounding
prostate
b. Bone or direct metastasis most
common
Prostate Cancer: Routes of Metastasis
Pathology, continued …
C. Prostatitis (accompanied by cystitis)
1. Inflammation of gland
2. Gland enlarges, becomes tender
3. Causes: gonorrhea? Other UTI’s?
STD’s?
4. May require antibiotics, massage
5. Symptoms: chills, painful urination,
back pain
Pathology, continued …
A. Prostatic concretions (aka:
corpora
amylacea [starch bodies])
1.
2.
3.
4.
Small spherical or ellipsoid bodies
Number increases with age
May become calcified as male ages
May simulate carcinoma
Digital Rectal Exam
Pathology, continued …
E. Rarely, prostatic abscesses develop
1. Frequently caused by gonorrhea
2. May rupture through to rectum, bladder,
perineum
3. Other causes:
a. Urethritis
b. Epididymitis