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KEY FACTS
Surgical Conditions
of the Canine Penis
and Prepuce
Aristotle University of Thessaloniki
Thessaloniki, Greece
Lysimachos G. Papazoglou, DVM, PhD, MRCVS
George M. Kazakos, DVM
ABSTRACT: Abnormalities of the canine penis and prepuce may have congenital or acquired
causes. Diagnosis is based mainly on physical examination of the external genitalia. Treatment
of these abnormalities may require surgical intervention or medical management. Because
many of the conditions may be hereditary, normal breeding is discouraged; therefore, surgical
treatment (whether emergency or elective) should be aimed at repairing urinary rather than
reproductive function.
Congenital and acquired penile and preputial abnormalities have been
described in dogs.1–3 Trauma is the main cause of acquired abnormali-
ties. Dogs with congenital or acquired abnormalities may be either
asymptomatic or have urinary dysfunction or breeding failure. Dogs that have
one defect should be examined thoroughly (especially in the midline) for the
presence of others.1–3
Because many penile and preputial defects are hereditary, normal breeding
should be discouraged; therefore, surgical intervention of congenital defects
should be aimed at correcting or preventing urinary dysfunction rather than
restoring reproductive performance. Traumatic abnormalities often require emer-
gency surgery to manage or prevent urinary dysfunction and reproductive failure.
Thorough knowledge of the pertinent anatomy and experience with surgical
reconstructive and urologic techniques are essential for a successful outcome.
SURGICAL CONDITIONS OF THE PENIS
Paraphimosis
The inability to retract the penis into the preputial cavity results in paraphi-
mosis. In a study of 185 dogs with penile and preputial diseases,4paraphimosis
was reported in 7%. Paraphimosis may be attributed mainly to an abnormally
small preputial orifice, ineffective preputial muscles, or a hypoplastic prepuce.
Other reported causes include trauma, infection, neoplasia, persistent erection,
or idiopathic causes.5–9 Paraphimosis is also encountered during sexual excite-
CE
204 Vol. 24, No. 3 March 2002
■Many penile and preputial
abnormalities are hereditary;
trauma is the main cause of
acquired defects.
■Dogs that have one defect should
be examined (especially in the
midline) for the presence of other
abnormalities.
■Emergency surgery is often
required in cases of traumatic
abnormalities to treat or prevent
urinary dysfunction or
reproductive failure.
Compendium March 2002 Penile and Preputial Surgery 205
ment (Figure 1) or coitus. The small preputial orifice
initially allows protrusion of the penis; but as the
penis becomes engorged and swollen the small orifice
makes retraction impossible. This may lead to severe
edema and congestion as well as dryness and irrita-
tion. Consequently, ischemic necrosis and urethral
obstruction may occur. Preputial hairs may encircle
the protruded penis and form a band that contributes
to or causes paraphimosis.3–10
Diagnosis of paraphimosis is made by physical exam-
ination. Determining the cause is essential for effective
treatment. If the prepuce can be drawn forward to
cover the penile protrusion, preputial muscle ineffec-
tiveness may be suspected as the cause.6
Medical treatment should be aimed initially at
retracting the penis into the preputial cavity. While the
dog is under general anesthesia or heavy sedation, cold
compresses consisting of hyperosmolar solutions and
lubricants should be applied to the penis to reduce the
swelling and facilitate retraction into the preputial cav-
ity. If retraction is impossible, surgical enlargement of
the prepuce is required. Paraphimosis accompanied by
penile necrosis is managed with amputation. Paraphi-
mosis that is attributed to preputial muscle ineffective-
ness, preputial hypoplasia, or idiopathic causes is man-
aged with cranial advancement of the prepuce
combined with shortening or imbrication of preputial
muscles (Figure 2).3,5,9,11,12 In a study of six dogs with
idiopathic paraphimosis in which preputial muscle
ineffectiveness had been implicated as a cause, results of
preputial advancement were considered excellent in
four dogs when the length of the exposed penis was 1.5
cm or less.9Longer protrusions, however, may also be
managed successfully using the same technique. In case
of recurrence or if the penis protrudes too far, partial
penile amputation or a staged reconstructive technique
may be performed to manage the paraphimosis.9,13,14
Hypospadias
Hypospadias is a rare developmental anomaly in
both male and female dogs in which the urethral ori-
fice is located ventral and proximal to the normal
opening.15,16 In male dogs, hypospadias is caused by
failure of the urethral folds to fuse when the urethra is
formed.1,17 This condition is most commonly seen in
male dogs with cryptorchidism and, to a lesser extent,
with other sexual defects.16 The etiology of hypospa-
dias seems to be multifactorial in association with
inadequate fetal androgen production.18 Boston terriers
reportedly have a familial predisposition to the devel-
opment of hypospadias.16 Anatomic classification of
Figure 1—Postcoital paraphimosis in a dog. Note the blood
and bumps.
Figure 2—A crescent-shaped piece of skin has been removed
cranial to the prepuce, and the preputial muscles have been
transected and excised (A). Reapposition is performed using a
horizontal mattress suture pattern (B). (From Papazoglou
LG: Idiopathic chronic penile protrusion in the dog: A report
of six cases. J Small Anim Pract 42:510–513, 2001; with per-
mission.)
Figure 3—Abnormal preputial fusion in association with
glandular hypospadias in a dog.
AB
206 Small Animal/Exotics Compendium March 2002
hypospadias may be glandular (Figure 3), penile, scro-
tal, or perineal, depending on the location of the ure-
thral opening.16 In addition to visual abnormalities,
clinical signs include hematuria, dysuria, and urinary
incontinence and scalding.
Diagnosis is made by physical examination of the
penis and perineum. Surgical correction depends on
the severity and location of the lesion.19 Usually a rea-
sonably sized urethral opening can be seen. Dogs with
mild defects may not require surgical correction19
because the urethra proximal to the abnormal orifice
is underdeveloped.7Dogs with severe irritation associ-
ated with an abnormally fused prepuce or a hypoplas-
tic penis may need resection of penile and preputial
remnants combined with a scrotal or perineal ure-
throstomy (Figures 4 and 5).7,19 In addition, castration
is always recommended because of the possible
genetic involvement.10,18
Trauma-Related Conditions
In a study of 185 dogs with penis and prepuce condi-
tions,4trauma accounted for 19% of the causes. Penile
trauma may result from motor vehicle accidents, ani-
mal fights, gunshot injuries, mating attempts, separa-
tion from the copulatory tie, or failing to clear fences
when jumping.6,17 Penile trauma may lead to hematoma
formation and strangulation and extensive necrosis of
the penis. Profuse hemorrhage and pain are the pre-
dominant clinical signs. Urethral obstruction and frac-
tured os penis can also be seen.6,20 Three recent cases21
of dogs with corpus cavernosum trauma possibly
caused by mating have been reported. All three dogs
were presented with signs of hindquarter pain, whereas
dysuria was noted in two of the animals.
Minor lacerations should be managed as open
wounds. In dogs with major lacerations or persistent
hemorrhage during excitement, suturing the tunica
albuginea with 4-0 or 5-0 synthetic monofilament
absorbable suture material (armed in a taper-cut nee-
dle) in a simple continuous or interrupted pattern is
recommended.7After surgery, analgesia or antibiotics
may be used (if needed) along with an Elizabethan col-
lar. Sedation and avoidance of contact with females are
recommended to prevent erection.6,7 If penile necrosis
occurs, however, partial or complete amputation of the
penis should be performed (Figures 4 and 6). If partial
penile amputation is performed, preputial shortening
may be required to prevent urine pooling in the
preputial cavity (Figure 7).12
Figure 4—Complete amputation of the external genitalia.
The skin around the prepuce and scrotum is incised in an
elliptical fashion (A). The penis is amputated proximal to the
os penis; and the distal penis, scrotum, and prepuce are
excised (B). A ligature is placed around the remaining penis,
and the penile stump is closed using a simple interrupted
suture pattern. The urethra is incised, and scrotal urethros-
tomy is performed by apposing urethral mucosa and skin in a
simple interrupted pattern with 3-0 or 4-0 nonabsorbable
monofilament suture material (C). The urethral mucosa may
be sutured to the skin in a simple continuous suture pattern
starting at the caudal aspect of the wound (D and E). This
pattern may result in decreased postoperative hemorrhage.
Figure 5—Perineal urethrostomy. The urethra is catheterized
and an incision made in the midline approximately 2 to 3
cm dorsal to the scrotum (A). The urethra is incised over
the catheter (B),and a urethrostomy is created by apposing
urethral mucosa and skin in a simple interrupted suture
pattern using 3-0 or 4-0 nonabsorbable monofilament
suture material (C).
ABCD
A
B
C
E
Compendium March 2002 Penile and Preputial Surgery 207
Tumors
Penile tumors account for 0.24% of all tumors in
male dogs22; transmissible venereal tumors (TVTs) and
squamous cell carcinomas (Figure 8) are the most com-
mon neoplasms of the canine penis.10,17 Other penile
tumors include fibromas, papillomas, and various mes-
enchymal tumors.6,10,23 Penile tumors usually affect
older dogs. In contrast, TVTs occur in young (mean
age, 4 to 5 years), free-roaming dogs and are transmit-
ted by contact with genital mucous membranes during
coitus.24 Clinical signs include preputial enlargement,
serosanguineous or hemorrhagic preputial discharge,
licking of the penis and prepuce, hematuria, dysuria,
and urethral obstruction.7,10
Diagnosis is based on physical examination and is
confirmed by cytology of fine-needle aspirate or
impression smear, incisional or excisional biopsy, and
histopathology.7,17,24 Clinical staging is essential for
squamous cell carcinomas because of the metastatic
potential.25 Vincristine chemotherapy (0.5 to 0.7
mg/m2IV in four to eight weekly cycles) is very effec-
tive in treating TVTs, even in dogs with metastatic dis-
ease.24,26 Doxorubicin is also effective.24 Radiotherapy is
recommended for animals that are resistant to
chemotherapy.24 Prognosis is usually very good. Surgical
excision is not recommended for TVTs because the
recurrence rate is high.26 Partial or complete penile
amputation combined with scrotal urethrostomy is rec-
ommended for penile tumors, depending on the loca-
tion and type of tumor. Perineal urethrostomy may also
be used in cases in which the tumor extends too far
proximal in the urethra (Figure 5). Ventral midline
preputiotomy may be employed, especially for penile
tumors that are large enough to allow penile extrusion
through the preputial orifice.27 Preputial closure is
accomplished in two layers. The mucosa is closed in a
simple continuous pattern with 4-0 or 5-0 synthetic
monofilament absorbable suture, and the skin is closed
in a routine fashion.27 The effect of adjuvant therapies
in prolonging survival has not been documented.25
Figure 6—Partial penile amputation. A catheter is placed in
the urethra and a Penrose tube is used as a tourniquet and for
preputial reflection (A). The penis is incised at a 45˚ angle.
The incision is made down to the os penis dorsally, and the
urethra is elevated from the groove of the os penis (B). The os
penis along with the amputated part of the penis is removed
with a rongeur. The penile stump is closed in a simple inter-
rupted suture pattern (C). The urethra is spatulated (D) and
sutured to the penile stump in a simple interrupted suture
pattern with 4-0 to 5-0 monofilament absorbable suture
material (E).
Figure 7—Preputial shortening. A portion of the prepuce is
excised full-thickness (A and B). The skin and mucosa are
reapposed in a simple interrupted suture pattern (C).
Figure 8—Squamous cell carcinoma of the penis and prepuce,
resulting in secondary phimosis.
A
B
C
D
ABC
E
Compendium March 2002 Penile and Preputial Surgery 209
Figure 9—Urethral prolapse in a castrated 4-year-old Yorkshire
terrier.
Figure 10—The prolapsed urethra has been resected, and the
urethral mucosa is sutured to the penile mucosa in a simple
interrupted suture pattern.
Figure 11—Persistent penile frenulum in a German short-
haired pointer.
Urethral Prolapse
Prolapse of the distal urethra through the external
urethral orifice is rarely reported in intact male dogs.7
Although this condition has been reported in two
Boston terriers, a Yorkshire terrier, and other breeds,
English bulldogs are mainly affected.28–31 Most of the
affected animals are young.32 The cause may be
unknown, or the condition may occur after excessive
sexual excitement or urogenital tract infection.7,23
Abnormal urethral anatomy in relation to increased
intraabdominal pressure caused by upper airway
obstructive syndrome, dysuria, and sexual excitement
have also been proposed to explain the increased
predilection in brachycephalic breeds.32 The prolapsed
urethra, which appears as a pea-shaped mass at the dis-
tal end of the penis, becomes edematous and con-
gested (Figure 9). Licking and intermittent hemor-
rhage, which becomes worse during erection, are the
usual clinical signs.6,7,31
Diagnosis is made by visual examination of the
penis. The condition should be differentiated from
fracture of the os penis, neoplasm, persistent penile
frenulum, urethral stricture, and urethral calculi.30 The
use of castration and hormonal therapy to prevent
erection has been unsuccessful.30,31 Surgical excision of
the prolapse is the treatment of choice, especially for
dogs with severe trauma and necrosis.10,30,33 The ventral
aspect of the penis is incised down to the penile and
urethral mucosa halfway around the circumference.30
The urethral mucosa is sutured to the penile mucosa
in a simple interrupted or continuous pattern17 using
4-0 synthetic monofilament absorbable suture. The
dorsal aspect of the urethral mucosa is then incised
and sutured with the same pattern (Figure 10).30 An
Elizabethan collar should be placed after surgery to
prevent licking of the anastomosis site. For 5 to 10
days, sedation and avoidance of contact with females
in estrus are also recommended to control postopera-
tive hemorrhage. If further trauma of the anastomosis
site is prevented, prognosis following surgical removal
is usually good.17 In rare cases in which urethral pro-
lapse recurs, re-excision is recommended.33
Persistent Penile Frenulum
Persistent penile frenulum is a thin band of connec-
tive tissue that unites the ventral midline aspect of the
glans penis to the prepuce. Rupture of the frenulum in
dogs occurs during puberty, and the process is con-
trolled by testosterone levels.6,7 The condition has been
reported in cocker spaniels, miniature poodles,
Pekingese, and mixed-breed dogs.17,34–36 Dogs with a
penile frenulum may be asymptomatic or may be pre-
sented with penile and preputial licking, urine scalding
of the hindlimbs caused by diversion of the urine
stream, pain during penile engorgement, unsuccessful
mating, and deviation of the penis during erection (i.e.,
phallocampsis).6,17,23
Diagnosis of penile frenulum is made by visual
examination (Figure 11). Treatment includes severing
the abnormal band with electrosurgery or a surgical
blade while the animal is under light anesthesia. Prog-
nosis following surgery is good.7Persistent penile
frenulum is sometimes accompanied by other congeni-
tal defects of the prepuce and penis that may require
reconstructive surgery.3,17
Hypoplastic Penis
Hypoplastic penis, which is an uncommon disorder,
usually occurs in association with other anomalies.17,23,37
This condition is often seen in intersex dogs.6,10,17 Dogs
with penile hypoplasia are usually asymptomatic; the
condition is often found incidentally during routine
clinical examination.6,10 In most cases, no treatment is
required.6,10 However, if the abnormality is accompa-
nied by a hypoplastic preputial orifice, urine pooling,
scalding inside the prepuce, or urine dribbling, then
212 Small Animal/Exotics Compendium March 2002
Figure 12—Transverse fracture of the os penis (arrow) in a
dog. (Courtesy of M. N. Patsikas, DVM, Aristotle University
of Thessaloniki, Greece.)
surgical intervention is necessary.37 Surgical enlarge-
ment of the preputial orifice can be accomplished by
making a triangular incision on the dorsal side of the
orifice; preputial shortening should be performed for
correction of the abnormality (Figure 7).12,37 However,
severe penile hypoplasia may be more easily managed
by amputation and scrotal urethrostomy.
Fracture of the Os Penis
Fracture of the canine os penis is a rarely reported
surgical condition.38,39 This condition can occur in any
size or breed of dog and often follows external penile
trauma.2,6 Simple fractures with minimal displacement
may go undetected, especially if accompanied by mini-
mal soft tissue injury.17 In the reported studies,4,38,39 the
most common presenting signs were associated with
urinary outflow obstruction (e.g., strangury, dysuria,
distended urinary bladder, uremia). Other signs
include local pain, inflammation, and urethral bleed-
ing.20,38 Palpation may reveal crepitus, but radiographic
examination will determine os penis damage and the
amount of callus formation, especially if the lesion is
old (Figure 12).38–40 Urethral catheterization and retro-
grade urography will determine urethral involvement
(e.g., tear, obstruction).4,6,38,39
T
reatment may not be necessary in dogs with mini-
mally displaced simple fractures.6,7,17,20 Mobile fractures
require immobilization (for 1 to 3 weeks) with the use
of a urinary catheter that should extend beyond the os
penis.4,17 More severe fractures may require plating,
wiring, or partial or total amputation of the penis.2,7,38,39
Urethral tears rarely need to be sutured and usually heal
around the catheter, except in cases in which complete
severance has occurred.17,20 Retrograde urography is rec-
ommended for 6 to 8 months after the fracture to mon-
Compendium March 2002 Penile and Preputial Surgery 213
Figure 14—Surgical correction of phimosis. A full-thickness,
V-shaped incision is made in the dorsal aspect of the prepuce
(A). The skin and preputial mucosa are apposed using a sim-
ple interrupted or continuous pattern (B).
AB
Figure 13—Priapism and self-induced traumatization of the
penis in a dog following intervertebral disk disease.
itor whether callus formation impedes urine passage.6In
one study,39 however, obstructive uropathy appeared 21
months after the fracture occurred. Urethral obstruction
caused by callus formation can be managed with ure-
throstomy distal to the obstruction site.17
Deformity of the Os Penis
Phallocampsis may be caused by deformity of the os
penis. Mild phallocampsis may result in the inability to
achieve vaginal penetration because of misdirected cop-
ulatory efforts, leading to infertility.10,41 This abnormal-
ity may predispose some dogs to urethral obstruction.10
Penile exposure results in drying of the exposed portion
of the penis, self-induced trauma, and eventually infec-
tion and necrosis.7,20
Treatment depends on the condition of the exposed
penis and is generally the same as for paraphimosis.7,20
Treatment may include fracturing the os penis with
wedge osteotomy and straightening it with the aid of
an indwelling urinary catheter and without fixa-
tion.7,20,41 Partial penile amputation may be performed
in severe cases (e.g., infection, necrosis).7However, if
no other problems (e.g., paraphimosis, outflow urine
obstruction) accompany the deformity, therapy may
not be indicated.10
Priapism
Priapism, which is rarely reported in dogs, is a per-
sistent penile erection not associated with sexual excite-
ment.7,10 The condition is either idiopathic or associ-
ated with spinal cord lesions (Figure 13), trauma
during mating, genitourinary infection, constipation,
thromboembolism of the cavernous venous tissue at the
base of the penis, or therapy for narcolepsy.2,7,42 Exces-
sive parasympathetic stimulation or decreased venous
outflow caused by an occlusive thrombosis or mass
results in stagnation of blood with increased carbon
dioxide and low oxygen concentrations in the corpus
cavernosum penis. This leads to edema with enhanced
venous obstruction and eventually irreversible fibrosis
in the main venous outflow tracts of the penis.42
This condition must be differentiated from frequent
erections seen in young small-breed dogs6and, at least
in early stages, from paraphimosis.7Chronic exposure
and excessive licking of the penis result in congestion,
swelling, and finally drying and necrosis, rendering dif-
ferentiation from paraphimosis difficult. Although
spontaneous remission can occur,7,17 delay in providing
supportive care may necessitate amputation. The penis
must be kept clean, lubricated with antibiotic creams to
prevent desiccation, and protected from self-induced
trauma.7,10,17 The erection should subside once the
spinal condition is resolved.7Amputation of the penis
and scrotal urethrostomy (Figure 4) may be necessary if
the underlying cause cannot be identified and cor-
rected.10,17 According to other reports, successful surgi-
cal treatment has consisted of incision of the bulbus
and pars longa glandis and exsanguination of accumu-
lated blood from the corpus cavernosum penis. The
ability to maintain an erection after surgery, however,
was not reported in the study.43
SURGICAL CONDITIONS OF THE PREPUCE
Phimosis
Phimosis is a condition in which the preputial orifice
is absent or too small to allow extrusion of the penis.44
In a study of 185 dogs with penile and preputial
lesions,4phimosis accounted for 0.5%. The condition
may be congenital or acquired. Congenital preputial
stenosis has been reported in Bouvier de Flandres, Ger-
man shepherds, Labrador and golden retrievers, and
mixed-breed dogs.6The most common causes of
acquired phimosis are scarring from lacerations follow-
ing trauma, sucking of the puppy’s prepuce by litter-
mates, and licking from the dam.7,17 Neoplasia in this
area may also narrow the preputial orifice.7,17 When the
preputial opening is large enough to allow urination,
puppies may be asymptomatic. In severely affected
dogs, either urine retention in the prepuce is noted or,
depending on the size of the orifice, urine dribbling or
an abnormal stream of urine is evident. Secondary
infections may lead to balanoposthitis and septicemia if
left untreated.2,6 Phimosis may interfere with erection
in sexually mature dogs.10,44
Diagnosis is made by inspecting an anatomically
small preputial opening in relation to the penis. In less
severe cases, it may be necessary to observe the erect
penis and its inability to be extruded from the preputial
orifice.10,44 Differentiation from persistent penile frenu-
lum should be made since phimosis can also result in
the inability of the penis to fully protrude from the pre-
puce.44 In congenital phimosis, in which the preputial
orifice is stenotic, it is possible to further evaluate the
penis and prepuce by performing a radiographic exami-
nation with the use of a contrast media injected into
the preputial cavity via the external opening.45
Surgical correction of the primary condition or
enlargement of the preputial orifice usually leads to a
successful outcome. Removal of neoplasms is usually
accompanied by aggressive removal of the prepuce and
sometimes partial penile amputation.7,46 Postsurgical
stenosis of the orifice should be avoided.7,46 Surgical
enlargement of the orifice should be performed on the
craniodorsal surface instead of the ventrocaudal aspect
to avoid excessive protrusion of the penis.12,46 A midline
full-thickness incision is made to the desired length to
ensure an unrestricted opening.12 It is sometimes neces-
sary to excise a V-shaped amount of tissue in order for
the penis to protrude normally (Figure 14).37 The
preputial mucosa and ipsilateral skin edges can be
apposed in a simple interrupted7or continuous pattern
using 4-0 or 5-0 synthetic monofilament nonab-
sorbable suture material to avoid irritation from
knots.46 If necessary, the incision may extend cranially
into the skin on the ventral abdominal wall.46
Neoplasms
All neoplastic diseases that affect the skin can be
found in the prepuce.7,8 Those most commonly
encountered include mastocytomas, TVTs, squamous
cell carcinomas, and perianal gland adenomas.7,8,25 As
they grow, tumors may obstruct the preputial orifice,
eventually causing phimosis. Ulcerations may favor
bacterial overgrowth; therefore, orifice involvement
may lead to balanoposthitis.44Preputial neoplasms may
sometimes extend to the penis.17
Diagnosis is made using cytology of fine-needle aspi-
rate or impression smear, incisional or excisional biopsy,
and histopathology.7,24 Clinical staging is required for
mast cell tumors and squamous cell carcinomas because
of their metastatic potential.25 Appropriate therapy
depends on tumor type, behavior, and metastases.
Treatment of small neoplasms includes surgical removal
of the mass with closure of the prepuce in two layers.7
Postoperative paraphimosis should be avoided.7Wide
surgical excision (partial or total preputial/penile ampu-
tation) should be included in the therapy plan for
malignant tumors.7,44 Radiotherapy or chemotherapy
may be required for mast cell tumors not amenable to
surgical excision or as an adjuvant therapy.47 Manage-
ment of preputial TVTs is the same as for penile
TVTs.24 Orchidectomy is advised in cases of perianal
gland tumors.
Trauma- and Foreign Body–Related Conditions
Preputial trauma may result from motor vehicle acci-
dents, dog fights, attempts to mate, environmental
injuries, gunshot injuries, or failing to clear fences when
jumping.6,17 In some cases only the external lamina is
involved; with full-thickness lacerations, both the exter-
nal and internal laminae may be involved.8Preputial
wounds, which may also result from foreign bodies
(e.g., grass awns, plant seeds, urinary calculi), usually
cause irritation or ulceration of the mucosa, leading to
mucopurulent or blood-tinged discharge, discomfort,
and mild hindlimb stiffness. A draining tract is usually
present ventral or lateral to the penis. Draining tract
exploration, foreign-body removal, and tract drainage
should be performed.7Prognosis is usually good after
foreign-body removal.7,10 For dogs with full-thickness
lacerations or those in which loss of tissue has occurred,
the prepuce should be closed in two layers.17 The
mucosa is closed in a continuous pattern with 4-0 or 5-
0 synthetic monofilament absorbable suture material,
and the skin is closed routinely. Measures aimed at pre-
venting self-induced trauma should be taken. Extensive
traumatic loss of the prepuce may be managed with
reconstructive staged surgery.14 Partial or complete
preputial and penile amputation should also be consid-
ered with injuries resulting from extensive trauma.17
Preputial Hypoplasia and Abnormal Fusion
The prepuce may be underdeveloped or absent or
may not fuse normally because of failure of the genital
folds to close normally during fetal life.7Abnormal
preputial fusion can be seen in association with
216 Small Animal/Exotics Compendium March 2002
hypospadias (Figure 3).6,15,48 Clinical signs are related to
chronic paraphimosis, which may lead to inflamma-
tion, drying, self-mutilation, and penile trauma.7,46
Paraphimosis may be managed successfully with cra-
nial advancement of the prepuce.9Severe preputial
hypoplasia usually requires staged reconstruction of
both preputial laminae using skin flaps and oral
grafts13,14; however, partial penile amputation remains
an alternative to reconstructive surgery.9Abnormal
preputial fusion may be treated by complete excision of
the exposed preputial mucosa, partial amputation of
the penis, and scrotal or perineal urethrostomy.7,12,48
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1. Cranial advancement of the prepuce should not be
performed in cases of
a. paraphimosis caused by preputial muscle ineffec-
tiveness.
b. idiopathic paraphimosis.
c. preputial hypoplasia.
d. paraphimosis following trauma.
2. Vincristine chemotherapy may be used to treat penile
TVTs at a dose of _______ mg/m2.
a. 0.2 c. 0.5 to 0.7
b. 0.1 d. 1
3. Which of the following statements regarding the treat-
ment of urethral prolapse is true?
a. Surgical excision of the prolapsed mass is necessary.
b. Spontaneous resolution of the prolapse is common.
c. Castration is effective in treating urethral prolapse.
d. Hormonal therapy should be included in the treat-
ment protocol for urethral prolapse.
4. Priapism may result from
a. a spinal cord lesion. c. genitourinary infection.
b. constipation. d. all of the above
5. Which of the following conditions is not included in
the diagnostic differentials of urethral prolapse?
a. stricture c. calculus
b.tumor d. phimosis
6. Which of the following tumors is commonly located
in the prepuce?
a. melanoma c. lymphoma
b. mastocytoma d. osteosarcoma
7. Which of the following is not recommended for the
treatment of preputial hypoplasia?
a. staged reconstructive surgery using skin flaps and
oral grafts
b. mesh skin graft
c. partial penile amputation
d. cranial preputial advancement
8. Which of the following conditions does not predispose
a dog to urethral obstruction?
a. persistent penile frenulum c. os penis fracture
b. os penis deformity d. paraphimosis
9. Which of the following statements regarding the man-
agement of hypospadias is false?
a. Dogs with hypospadias always require surgical cor-
rection.
b. Dogs with mild hypospadias may require no surgi-
cal treatment.
c. Dogs with severe hypospadias may need penile
amputation and urethrostomy.
d. Surgical correction depends on the severity and
location of hypospadias.
10. The prepuce in dogs with full-thickness lacerations
should be closed
a. using one suture layer.
b. using two suture layers.
c. using healing by second intention.
d. by suturing the mucosa with nonabsorbable suture
material.
218 Small Animal/Exotics Compendium March 2002
CE
ARTICLE #2 CE TEST
The article you have read qualifies for 1.5 con-
tact hours of Continuing Education Credit from
the Auburn University College of Veterinary Med-
icine. Choose the best answer to each of the follow-
ing questions; then mark your answers on the
postage-paid envelope inserted in Compendium.
