Male Urogenital Triangle-Penis-Scrotum-Testes-Epididymides-Female Urogenital Triangle-Vulva-Mons Pubis-Labia Majora-Labia Minora-Vestibule-Vaginal Orifice-Clitoris

Male Urogenital Triangle

The male urogenital triangle contains the penis and the scrotum.

Penis

The penis consists of a root, a body, and a glans. The root of the penis consists of three masses of erectile tissue called the bulb of the penis and the right and left crura of the penis. The bulb can be felt on deep palpation in the midline of the perineum, posterior to the scrotum.

The body of the penis is the free portion of the penis, which is suspended from the symphysis pubis. Note that the dorsal surface (anterior surface of the flaccid organ) usually possesses a superficial dorsal vein in the midline The glans penis forms the extremity of the body of the penis. At the summit of the glans is the external urethral meatus. Extending from the lower margin of the external meatus is a fold connecting the glans to the prepuce called the frenulum. The edge of the base of the glans is called the corona. The prepuce or foreskin is formed by a fold of skin attached to the neck of the penis. The prepuce covers the glans for a variable extent, and it should be possible to retract it over the glans.

Scrotum

The scrotum is a sac of skin and fascia containing the testes and the epididymides. The skin of the scrotum is rugose and is covered with sparse hairs. The bilateral origin of the scrotum is indicated by the presence of a dark line in the midline, called the scrotal raphe, along the line of fusion
.

Testes

The testes should be palpated. They are oval shaped and have a firm consistency. They lie free within the tunica vaginalis and are not tethered to the subcutaneous tissue or skin.

Epididymides

Each epididymis can be palpated on the posterolateral surface of the testis. The epididymis is a long, narrow, firm structure having an expanded upper end or head, a body, and a pointed tail inferiorly. The cordlike vas deferens emerges from the tail and ascends medial to the epididymis to enter the spermatic cord at the upper end of the scrotum.

Female Urogenital Triangle

Vulva

“Vulva” is the term applied to the female external genitalia

Mons Pubis

The mons pubis is the rounded, hair-bearing elevation of skin found anterior to the pubis. The pubic hair in the female has an abrupt horizontal superior margin, whereas in the male it extends upward to the umbilicus.

Labia Majora

The labia majora are prominent, hair-bearing folds of skin extending posteriorly from the mons pubis to unite posteriorly in the midline
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Labia Minora

The labia minora are two smaller, hairless folds of soft skin that lie between the labia majora . Their posterior ends are united to form a sharp fold, the fourchette. Anteriorly, they split to enclose the clitoris, forming an anterior prepuce and a posterior frenulum

Vestibule

The vestibule is a smooth triangular area bounded laterally by the labia minora, with the clitoris at its apex and the fourchette at its base.

Vaginal Orifice

The vaginal orifice is protected in virgins by a thin mucosal fold called the hymen, which is perforated at its center. At the first coitus, the hymen tears, usually posteriorly or posterolaterally, and after childbirth only a few tags of the hymen remain .

Clitoris

This is situated at the apex of the vestibule anteriorly. The glans of the clitoris is partly hidden by the prepuce.

Vagina-Supports of the Vagina-Blood Supply-Vulva-Nerve Supply-Vulval Infection-The Vulva and Pregnancy-Urethral Infection-Urethral Injuries-Catheterization

Vagina

The vagina not only is the female genital canal but also serves as the excretory duct for the menstrual flow from the uterus and forms part of the birth canal. This muscular tube extends upward and backward between the vulva and the uterus (see Fig. 8.4). It measures about 3 in. (8 cm) long. The cervix of the uterus pierces its anterior wall. The vaginal orifice in a virgin possesses a thin mucosal fold, called the hymen, which is perforated at its center. The upper half of the vagina lies above the pelvic floor within the pelvis between the bladder anteriorly and the rectum posteriorly; the lower half lies within the perineum between the urethra anteriorly and the anal canal posteriorly
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Supports of the Vagina

■■ Upper third: Levatores ani muscles and transverse cervical, pubocervical, and sacrocervical ligaments

■■ Middle third: Urogenital diaphragm

■■ Lower third: Perineal body

Blood Supply

Arteries

The vaginal artery, a branch of the internal iliac artery, and the vaginal branch of the uterine artery supply the vagina.

Vulva

The term vulva is the collective name for the female external genitalia and includes the mons pubis, labia majora and minora, the clitoris, the vestibule of the vagina, the vestibular bulb, and the greater vestibular glands.

Blood Supply

Branches of the external and internal pudendal arteries on each side.

The skin of the vulva is drained into the medial group of superficial inguinal nodes.

Lymph Drainage

Medial group of superficial inguinal nodes
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Nerve Supply

The anterior parts of the vulva are supplied by the ilioinguinal nerves and the genital branch of the genitofemoral nerves. The posterior parts of the vulva are supplied by the branches of the perineal nerves and the posterior cutaneous nerves of the thigh.

Vulval Infection

In the region of the vulva, the presence of numerous glands and ducts opening onto the surface makes this area prone to infection. The sebaceous glands of the labia majora, the ducts of the greater vestibular glands, the vagina (with its indirect communication with the peritoneal cavity), the urethra, and the paraurethral glands can all become infected. The vagina itself has no glands and is lined with stratified squamous epithelium. Provided that the pH of its interior is kept low, it is capable of resisting infection to a remarkable degree.

The Vulva and Pregnancy

An important sign in the diagnosis of pregnancy is the appearance of a bluish discoloration of the vulva and vagina as a result of venous congestion. It appears at the 8th to 12th week and increases as the pregnancy progresses.

Urethral Infection

The short length of the female urethra predisposes to ascending infection; consequently, cystitis is more common in females than in males.

Urethral Injuries

Because of the short length of the urethra, injuries are rare. In fractures of the pelvis, the urethra may be damaged by shearing forces as it emerges from the fixed urogenital diaphragm.

Catheterization

Because the female urethra is shorter, wider, and more dilatable, catheterization is much easier than in males. Moreover, the urethra is straight, and only minor resistance is felt as the catheter passes through the urethral sphincter.