Corpus spongiosum penis

Corpus spongiosum penis

Lower Parts of the Genital and Urinary Tracts in the Male

Dissection of the Penis
Details
Latin Corpus spongiosum penis
(plural: Corpora spongiosa penium),
(corpus cavernosum urethrae)
Identifiers
Gray's p.1248
Dorlands
/Elsevier		 c_56/12260814
TA A09.4.01.015
FMA 19617
Anatomical terminology

The corpus spongiosum is the mass of spongy tissue surrounding the male urethra within the penis. Although called corpus cavernosum in older texts (reference title and dates needed) , this is not correct.

Anatomy

Behind, it is expanded to form the urethral bulb, and lies in apposition with the inferior fascia of the urogenital diaphragm, from which it receives a fibrous investment.

The urethra enters the bulb nearer to the superior than to the inferior surface. On the latter there is a median sulcus (groove), from which a thin fibrous septum (wall) projects into the substance of the bulb and divides it imperfectly into two lateral lobes or hemispheres.

The portion of the corpus spongiosum in front of the bulb lies in a groove on the under surface of the conjoined corpora cavernosa penis. It is cylindrical in form and tapers slightly from behind forward. Its anterior end is expanded in the form of an obtuse cone, flattened from above downward. This expansion, termed the glans penis, is moulded on the rounded ends of the corpora cavernosa penis, extending farther on their upper than on their lower surfaces.

At the summit of the glans is the slit-like vertical external urethral orifice, also known as the meatus.

The circumference of the base of the glans forms a rounded projecting border, the corona glandis, overhanging a deep retroglandular sulcus (Meiring's sulcus), behind which is the neck of the penis.

Function

The function of the corpus spongiosum in erection is to prevent the urethra from pinching closed, thereby maintaining the urethra as a viable channel for ejaculation. To do this, the corpus spongiosum remains pliable during erection while the corpora cavernosum penis becomes engorged with blood.

Additional images

See also

References

This article incorporates text in the public domain from the 20th edition of Gray's Anatomy (1918)

External links