The spongy urethra (cavernous portion of urethra, penile urethra) is the longest part of the

male urethra The urethra (: urethras or urethrae) is the tube that connects the urinary bladder to the urinary meatus, through which placental mammals urinate and ejaculate. The external urethral sphincter is a striated muscle that allows voluntary contro ...

, and is contained in the corpus spongiosum of the

penis A penis (; : penises or penes) is a sex organ through which male and hermaphrodite animals expel semen during copulation (zoology), copulation, and through which male placental mammals and marsupials also Urination, urinate. The term ''pen ...

. In humans, it is about 15 cm long, and extends from the termination of the membranous portion to the external urethral orifice. Commencing below the inferior fascia of the

urogenital diaphragm Older texts have asserted the existence of a urogenital diaphragm, also called the triangular ligament, which was described as a layer of the pelvis that separates the deep perineal sac from the upper pelvis, lying between the inferior fascia of ...

it passes forward and upward to the front of the

pubic symphysis The pubic symphysis (: symphyses) is a secondary cartilaginous joint between the left and right superior rami of the pubis of the hip bones. It is in front of and below the urinary bladder. In males, the suspensory ligament of the penis attache ...

; and then, in the

flaccid Flaccid paralysis is a neurological condition characterized by weakness or paralysis and reduced muscle tone without other obvious cause (e.g., trauma). This abnormal condition may be caused by disease or by trauma affecting the nerves assoc ...

condition of the

, it bends downward and forward. It is narrow, and of uniform size in the body of the penis, measuring about 6 mm in diameter; it is dilated behind, within the bulb, and again anteriorly within the

glans penis In male human anatomy, the glans penis or penile glans, commonly referred to as the glans, (; from Latin ''glans'' meaning "acorn") is the bulbous structure at the Anatomical terms of location#Proximal and distal, distal end of the human penis ...

, where it forms the fossa navicularis urethrae. The spongy urethra runs along the length of the penis on its ventral (underneath) surface. It is about 15–16 cm in length, and travels through the corpus spongiosum. The ducts from the urethral gland (gland of Littré) enter here. The openings of the bulbourethral glands are also found here.Atlas of Human Anatomy 5th Edition, Netter. Some textbooks will subdivide the spongy urethra into two parts, the bulbous and pendulous urethra. The urethral lumen (interior) runs effectively parallel to the penis, except at the narrowest point, the

external urethral meatus The urinary meatus (, ; : meati or meatuses), also known as the external urethral orifice, is the opening of the penis or vulva where urine exits the urethra during urination. It is also where semen exits during male ejaculation, and other fluids ...

, where it is vertical. This produces a spiral stream of urine and has the effect of cleaning the external urethral meatus. The lack of an equivalent mechanism in the female urethra partly explains why urinary tract infections occur so much more frequently in females.

Epithelium

Pseudostratified columnar – proximally, Stratified squamous – distally

Additional images

File:Illu penis.jpg, Structure of the penis. File:Illu repdt male.jpg, Male reproductive system.

References

External links

* * - "The Male Pelvis: The Urethra" {{Authority control Male urethra