The male urethra is a pelvic urinary body organ that functions primarily together a connecting cord i beg your pardon transports urine from the urinary bladder to the exterior. ~ above the superior end of the bladder is a pair of 25-30 cm lengthy muscular tubes, the ureters, which additionally connect and fills the bladder through urine created in the kidneys.

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The male urethra is one 18-22 cm long muscular tube that conveys urine from the urinary bladder. Thus it operation from the internal urethral orifice that the bladder to the external urethral orifice situated at the tip of the glans penis. The urethra likewise functions to provide an exit for semen (sperm) and glandular secretions) during ejaculation.

Thus, in males, the urethra is a component of the urinary system as well as the reproductive system. While the urethra runs the length of the dick in males, in females, it is very short and it is not component of the reproductive system.

once the prick is in a flaccid (non-erect) state, the urethra presents a dual curvature and is divisible into 4 parts, which are the:

Preprostatic (intramural) part Prostatic urethra Membranous (intermediate) urethra Spongy (Penile) urethra vital facts around the male urethra
components Preprostatic, prostatic, membranous, spongy components
Histology Transitional and also stratified squamous epithelia
Arterial it is provided Prostatic branches the the inferior vesical and middle rectal arteries
Venous drainage Dorsal vein the the penis and also pudendal veins
Innervation Prostatic plexus

Contents
Gross features Vasculature and also lymphaticsClinical notes
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Embryology

early on in the fourth week the embryonic development, the urinary mechanism develops. It is composed of the urinary system,kidneys, ureters, urinary bladder and also the urethra. The urethra is mainly derived from a heavy cord of ectodermal cells that grows inward from the guideline of the glans penis and also joins the rest of the spongy urethra.

The epithelium that the terminal part (part close to the glans) of the urethra creates from the surface ectoderm, when epithelium lining the remaining parts of the urethra is acquired from endoderm the the urogenital sinus. The connective tissue and smooth muscle that the urethra establishes from the splanchnic mesenchyme.

Histology

The wall of the urethra is comprised of mucous, submucous and muscular layers. The prostatic urethra is bounded through prostatic tissue, while the penile urethra (spongy urethra) by erectile organization of the body spongiosum. The mucous membrane consists a lining pseudostratified columnar epithelium, mostly transitional epithelium top top the short component adjoining the urinary bladder and also stratified squamous epithelium on the component near the external urethral orifice.

The submucosa consists of loose connective tissue, if the muscular coat is made up of an within longitudinal layer and also an outer circular layer of smooth muscle. In addition, the membranous part is surrounded by striated muscle that forms the outside urethral sphincter.

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male urethra (histological slide)

gun features

Preprostatic urethra

The early part, i m sorry passes through the bladder musculature (“bladder neck”), just below the inner urethral orifice, is described as the pre-prostatic urethra or intramural part the the urethra. Ideally that is about 0.5-1.5 centimeter in length yet varies depending upon whether the bladder is filled with urine or empty.

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Penis and urethra (overview)

Prostatic urethra

The prostatic urethra is the component of the urethra that passes through the prostate. That is about 3-4 centimeter long and also extends from the base of the bladder, just below the pre-prostatic urethra, to the membranous component of the urethra.

The prostatic urethra is surrounding by the internal urethral sphincter close to its center part; that is widest in the middle. The posterior component of the urethra has actually an elevation referred to as the urethral crest; the prostatic sinuses open up up top top either next of this crest, which lug prostatic liquid into the urethral lumen. The ejaculatory ducts likewise open increase in the prostatic urethra, which bring the sperms from the testes and the fluid from the seminal vesicles into the urethra. Thus the urinary and reproductive tracts merge at this point.

This is a usual site the obstruction come the outflow of pee in patients v benign hypertrophy that the prostate.

Membranous urethra

The membranous or intermediate part the the urethra is the second shortest part of the urethra that connects the prostatic urethra come the penile urethra. It is 1-1.5 centimeter long and also it is surrounding by the external urethral sphincter. The exterior urethral sphincter plays crucial role in voluntary control of urinary flow.

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male urethra in a cadaver: In a common dissection the the masculine urethra, the lumen should be one empty, consistent tube. However, urinary bladder stones deserve to sometimes lodge within the urethra, obstructing the urinary flow. In the pear of the penis, the urethra bends sharply and passes through the perineal membrane.

Spongy (penile) urethra

The spongy urethra is the last and largest part the the urethra. It is roughly 15 cm long and also is divisible right into two main parts - the pendulous urethra and the bulbar urethra. The pendulous urethra runs follow me the length of the penis, while the bulbar urethra is located in the bulb of the penis. The spongy urethra opens up to the external through the urethral meatus (external urethral orifice), which is a vertical slit-like opening slightly behind the tip of the penis. The bulbourethral glands and the glands that Littre open into the spongy urethra.


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The arterial it is provided of the masculine urethra contains the prostatic branches that the inferior vesical and middle rectal arteries.

Venous return

Veins of the urethra, such together the dorsal veins of the penis and the pudendal veins, drainpipe into the prostatic venous plexus.

Lymphatic drainage

The lymphatic ship of the urethra drain mainly into the internal iliac lymph nodes. Some others drain into the external iliac lymph nodes.

Innervation

The urethra is innervated through the prostatic plexus. The prostatic plexus includes nerves through a mixture that fibres derived from the sympathetic and parasympathetic trunks, as well as from visceral afferent fibres. Such nerves are referred to as “mixed nerves” since they save afferent and efferent fibres.

an ext information about the anatomy that the masculine urinary bladder and also urethra is listed below:


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cock discover study unit

Clinical notes

Developmental disorders

Common congenital malformations affecting the male urethra includes hypospadias and also epispadias in i beg your pardon the meatus (external urethra orifice) is not located at the distal finish of the penis.

In hypospadias, over there is a cleft on the floor that the urethra owing to one arrest the union in the middle line. It occurs reduced than normal, and sometimes the deficiency is confined to the glans penis. The urethra end at the suggest where the extremity of the prepuce joins the body of the penis, in a tiny valve-like opening. The prepuce is additionally cleft top top its under surface and forms a kind of hood over the glans. There is a depression ~ above the glans in the place of the normal meatus. This problem produces no disability and requires no treatment.In epispadias, the meatus is located higher than normal. That is a much much more uncommon type of malformation in which there is an noticeable deficiency the the upper wall of the urethra. The deficiency may vary in extent; when it is finish the condition is connected with one extroversion of the bladder. In less extensive cases, wherein there is no extroversion, there is an infundibuliform opening into the bladder. The dick is typically dwarfed and also turned upward, so the the glans lies over the opening.In a severe condition referred to as chordee, the urethra have the right to develop in between the penis and also scrotum. In this condition, the cavernous section of the urethra is cleft throughout its whole length, and the opening of the urethra is in ~ the point of junction of the penis and also scrotum. The under surface of the penis in the middle line gift a furrow lined by a moist mucous membrane, on either side of which is often an ext or less dense fibrous tissue extending from the glans to the opening of the urethra, which stays clear of complete erection taking place. An excellent discomfort is induced during micturition, and sexual connection is impossible.

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Urethritis and urethral strictures

Infectious conditions such as urethritis also affect the male urethra however are an extremely rare. Additionally passage the kidney stones with the urethra have the right to be very painful and may cause a condition known as urethral strictures.