Jump to content

Glans penis: Difference between revisions

From Wikipedia, the free encyclopedia
Browse history interactively
[pending revision][pending revision]
← Previous editNext edit →
Content deleted Content added
VisualWikitext
Line 30: Line 30:
==Anatomical details==
==Anatomical details==


The glans [[penis]] is the expanded cap of the [[corpus spongiosum]]. It is moulded on the rounded ends of the [[Corpores cavernosa penis|Corpus cavernosum 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. The circumference of the base of the glans forms a rounded projecting border, the [[corona glandis]], overhanging a deep retroglandular [[Sulcus (anatomy)|sulcus]] (the ''coronal sulcus''), behind which is the neck of the penis. The proportional size of the glans penis can vary greatly. On some penises it is much wider in circumference than the [[shaft]], giving the penis a [[mushroom]]-like appearance, and on others it is narrower and more akin to a probe in shape. It has been suggested that the unique and unusual shape of the glans in humans has evolved to serve the function of "scooping" any remnant [[semen]] deposited by other rival males out of the deeper part of the [[vagina]] of a female who may have recently copulated, and thereby decreasing the chance of the rival male from impregnating the female.<ref name="gallup">{{cite journal | last = Gallup | first = Gordon | coauthors = Rebecca L. Burch, Mary L. Zappieri, Rizwan A. Parvez, Malinda L. Stockwell, Jennifer A. Davis | year = 2003 | month = July | title = The human penis as a semen displacement device | journal = Evolution and Human Behavior | volume = 24 | issue = 4 | pages = 277–289 | url =http://www.journals.elsevierhealth.com/periodicals/ens/article/PIIS1090513803000163/abstract | doi = 10.1016/S1090-5138(03)00016-3}}</ref> Other theorists{{Who|date=April 2009}} suggest that its distinctive shape evolved to heighten the sexual pleasure experienced by the female during vaginal intercourse. In this theory, the glans increases friction and tension at the mouth of the [[vagina]] by its additional girth and the dilating properties of its probe-like shape. This maximises indirect stimulation of the [[clitoris]] by the repetitive thrusting movements of the penis inside the vagina during intercourse.
The glans [[penis]] is the expanded cap of the [[corpus spongiosum]]. It is moulded on the rounded ends of the [[Corpus cavernosum penis|Corpores 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. The circumference of the base of the glans forms a rounded projecting border, the [[corona glandis]], overhanging a deep retroglandular [[Sulcus (anatomy)|sulcus]] (the ''coronal sulcus''), behind which is the neck of the penis. The proportional size of the glans penis can vary greatly. On some penises it is much wider in circumference than the [[shaft]], giving the penis a [[mushroom]]-like appearance, and on others it is narrower and more akin to a probe in shape. It has been suggested that the unique and unusual shape of the glans in humans has evolved to serve the function of "scooping" any remnant [[semen]] deposited by other rival males out of the deeper part of the [[vagina]] of a female who may have recently copulated, and thereby decreasing the chance of the rival male from impregnating the female.<ref name="gallup">{{cite journal | last = Gallup | first = Gordon | coauthors = Rebecca L. Burch, Mary L. Zappieri, Rizwan A. Parvez, Malinda L. Stockwell, Jennifer A. Davis | year = 2003 | month = July | title = The human penis as a semen displacement device | journal = Evolution and Human Behavior | volume = 24 | issue = 4 | pages = 277–289 | url =http://www.journals.elsevierhealth.com/periodicals/ens/article/PIIS1090513803000163/abstract | doi = 10.1016/S1090-5138(03)00016-3}}</ref> Other theorists{{Who|date=April 2009}} suggest that its distinctive shape evolved to heighten the sexual pleasure experienced by the female during vaginal intercourse. In this theory, the glans increases friction and tension at the mouth of the [[vagina]] by its additional girth and the dilating properties of its probe-like shape. This maximises indirect stimulation of the [[clitoris]] by the repetitive thrusting movements of the penis inside the vagina during intercourse.


The foreskin maintains the mucosa in a moist environment.<ref name="prakash">{{cite journal | last = Prakash | first = Satya | coauthors = Raghuram Rao, K. Venkatesan & S. Ramakrishnan | year = 1982 | month = July | title = Sub-Preputial Wetness--Its Nature | journal = Annals of National Medical Science (India) | volume = 18 | issue = 3 | pages = 109–112 | url =http://www.cirp.org/library/anatomy/prakash/}}</ref> In males who have been [[circumcision|circumcised]], but have not undergone [[foreskin restoration|restoration]], the glans is permanently exposed and dry. Szabo and Short found that the glans of the circumcised penis does not develop a thicker keratinization layer.<ref name="szabo">{{cite journal | last = Szabo | first = Robert | coauthors = Roger V. Short | year = 2000 | month = June | title = How does male circumcision protect against HIV infection? | journal = British Medical Journal | volume = 320 | issue = 7249 | pages = 1592–4 | pmid = 10845974 | url =http://bmj.bmjjournals.com/cgi/content/full/320/7249/1592 | accessdate = 2006-07-07 | doi = 10.1136/bmj.320.7249.1592 | pmc = 1127372 }}</ref> Studies have suggested that the glans is equally sensitive in circumcised and uncircumcised males.<ref name="masters">{{cite book | last = Masters | first = William H. | coauthors = Virginia E. Johnson | title = Human Sexual Response | year = 1966 | publisher = Little, Brown & Co | location = Boston | isbn = 0-316-54987-8 | pages = 189–91}} (excerpt accessible [http://www.circs.org/library/masters/ here])</ref> <ref name="bleustein">{{cite journal | last = Bleustein | first = Clifford B. | coauthors = James D. Fogarty, Haftan Eckholdt, Joseph C. Arezzo and Arnold Melman | year = 2005 | month = April | title = Effect of neonatal circumcision on penile neurologic sensation | journal = Urology | volume = 65 | issue = 4 | pages = 773–7 | doi = 10.1016/j.urology.2004.11.007 | pmid = 15833526 }}</ref>
The foreskin maintains the mucosa in a moist environment.<ref name="prakash">{{cite journal | last = Prakash | first = Satya | coauthors = Raghuram Rao, K. Venkatesan & S. Ramakrishnan | year = 1982 | month = July | title = Sub-Preputial Wetness--Its Nature | journal = Annals of National Medical Science (India) | volume = 18 | issue = 3 | pages = 109–112 | url =http://www.cirp.org/library/anatomy/prakash/}}</ref> In males who have been [[circumcision|circumcised]], but have not undergone [[foreskin restoration|restoration]], the glans is permanently exposed and dry. Szabo and Short found that the glans of the circumcised penis does not develop a thicker keratinization layer.<ref name="szabo">{{cite journal | last = Szabo | first = Robert | coauthors = Roger V. Short | year = 2000 | month = June | title = How does male circumcision protect against HIV infection? | journal = British Medical Journal | volume = 320 | issue = 7249 | pages = 1592–4 | pmid = 10845974 | url =http://bmj.bmjjournals.com/cgi/content/full/320/7249/1592 | accessdate = 2006-07-07 | doi = 10.1136/bmj.320.7249.1592 | pmc = 1127372 }}</ref> Studies have suggested that the glans is equally sensitive in circumcised and uncircumcised males.<ref name="masters">{{cite book | last = Masters | first = William H. | coauthors = Virginia E. Johnson | title = Human Sexual Response | year = 1966 | publisher = Little, Brown & Co | location = Boston | isbn = 0-316-54987-8 | pages = 189–91}} (excerpt accessible [http://www.circs.org/library/masters/ here])</ref> <ref name="bleustein">{{cite journal | last = Bleustein | first = Clifford B. | coauthors = James D. Fogarty, Haftan Eckholdt, Joseph C. Arezzo and Arnold Melman | year = 2005 | month = April | title = Effect of neonatal circumcision on penile neurologic sensation | journal = Urology | volume = 65 | issue = 4 | pages = 773–7 | doi = 10.1016/j.urology.2004.11.007 | pmid = 15833526 }}</ref>

Revision as of 01:49, 25 May 2010

male sexual organs
File:Male anatomy.png
1. Testicles
2. Epididymis
3. Corpus cavernosa
4. Foreskin
5. Frenulum
6. Urethral opening
7. 8. Corpus spongiosum
9. Penis
10. Scrotum
Details
ArteryUrethral artery
Identifiers
LatinGraySubject = 262
TA98A09.4.01.007
TA23668
FMA18247
Anatomical terminology

The Glans Penis (or simply Glans) is the sensitive bulbous structure at the distal end of the penis. The glans penis is anatomically homologous to the clitoral glans of the female. When the penis is flaccid it is sometimes wholly or partially covered by the foreskin, except in men who have been fully circumcised.

Medical considerations

The meatus (opening) of the urethra is at the tip of the glans penis. In circumcised infants, the foreskin no longer protects the meatal area of the glans; consequently, when wearing diapers, there may be greater risk of developing meatitis, meatal ulceration, and meatal stenosis.[1]

The epithelium of the glans penis is mucocutaneous tissue.[2] Birley et al. report that excessive washing with soap may dry the mucous membrane that covers the glans penis and cause non-specific dermatitis.[3]

Inflammation of the glans penis is known as balanitis. It occurs in 3–11% of males, and up to 35% of diabetic males. It is more common among uncircumcised males.[4] It has many causes, including irritation, or infection with a wide variety of pathogens. Careful identification of the cause with the aid of patient history, physical examination, swabs and cultures, and biopsy are essential in order to determine the proper treatment.[4]

Anatomical details

The glans penis is the expanded cap of the corpus spongiosum. It is moulded on the rounded ends of the Corpores 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. The circumference of the base of the glans forms a rounded projecting border, the corona glandis, overhanging a deep retroglandular sulcus (the coronal sulcus), behind which is the neck of the penis. The proportional size of the glans penis can vary greatly. On some penises it is much wider in circumference than the shaft, giving the penis a mushroom-like appearance, and on others it is narrower and more akin to a probe in shape. It has been suggested that the unique and unusual shape of the glans in humans has evolved to serve the function of "scooping" any remnant semen deposited by other rival males out of the deeper part of the vagina of a female who may have recently copulated, and thereby decreasing the chance of the rival male from impregnating the female.[5] Other theorists[who?] suggest that its distinctive shape evolved to heighten the sexual pleasure experienced by the female during vaginal intercourse. In this theory, the glans increases friction and tension at the mouth of the vagina by its additional girth and the dilating properties of its probe-like shape. This maximises indirect stimulation of the clitoris by the repetitive thrusting movements of the penis inside the vagina during intercourse.

The foreskin maintains the mucosa in a moist environment.[6] In males who have been circumcised, but have not undergone restoration, the glans is permanently exposed and dry. Szabo and Short found that the glans of the circumcised penis does not develop a thicker keratinization layer.[7] Studies have suggested that the glans is equally sensitive in circumcised and uncircumcised males.[8] [9]

Halata & Munger (1986) report that the density of genital corpuscles is greatest in the corona glandis,[10] while Yang & Bradley (1998) report that their study "showed no areas in the glans to be more densely innervated than others."[11]

Halata & Spathe (1997) reported that "the glans penis contains a predominance of free nerve endings, numerous genital end bulbs and rarely Pacinian and Ruffinian corpuscles. Merkel nerve endings and Meissner's corpuscles are not present."[2]

Yang & Bradley argue that "The distinct pattern of innervation of the glans emphasizes the role of the glans as a sensory structure".[11]

Additional images

  • An anterior view of a male's flaccid penis with the covering foreskin pulled back fully and the glans underneath fully exposed
    An anterior view of a male's flaccid penis with the covering foreskin pulled back fully and the glans underneath fully exposed

See also

References

  1. ^ Freud, Paul (1947). "The ulcerated urethral meatus in male children". The Journal of Pediatrics. 31 (2): 131–41. doi:10.1016/S0022-3476(47)80098-8. Retrieved 2006-07-07. {{cite journal}}: Unknown parameter |month= ignored (help)
  2. ^ a b Halata, Zdenek (1997). "Sensory innervation of the human penis". Advances in experimental medicine and biology. 424 (424): 265–6. PMID 9361804. Retrieved 2006-07-07. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
  3. ^ Birley, H. D. (1993). "Clinical features and management of recurrent balanitis; association with atopy and genital washing". Genitourinary Medicine. 69 (5): 400–3. PMC 1195128. PMID 8244363. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help); line feed character in |coauthors= at position 67 (help)
  4. ^ a b Edwards, Sarah (1996). "Balanitis and balanoposthitis: a review". Genitourinary Medicine. 72 (3): 155–9. PMC 1195642. PMID 8707315. {{cite journal}}: Unknown parameter |month= ignored (help)
  5. ^ Gallup, Gordon (2003). "The human penis as a semen displacement device". Evolution and Human Behavior. 24 (4): 277–289. doi:10.1016/S1090-5138(03)00016-3. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help)
  6. ^ Prakash, Satya (1982). "Sub-Preputial Wetness--Its Nature". Annals of National Medical Science (India). 18 (3): 109–112. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help)
  7. ^ Szabo, Robert (2000). "How does male circumcision protect against HIV infection?". British Medical Journal. 320 (7249): 1592–4. doi:10.1136/bmj.320.7249.1592. PMC 1127372. PMID 10845974. Retrieved 2006-07-07. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help)
  8. ^ Masters, William H. (1966). Human Sexual Response. Boston: Little, Brown & Co. pp. 189–91. ISBN 0-316-54987-8. {{cite book}}: Unknown parameter |coauthors= ignored (|author= suggested) (help) (excerpt accessible here)
  9. ^ Bleustein, Clifford B. (2005). "Effect of neonatal circumcision on penile neurologic sensation". Urology. 65 (4): 773–7. doi:10.1016/j.urology.2004.11.007. PMID 15833526. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help)
  10. ^ Halata, Zdenek (1986). "The neuroanatomical basis for the protopathic sensibility of the human glans penis". Brain Research. 371 (2): 205–30. doi:10.1016/0006-8993(86)90357-4. PMID 3697758. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help)
  11. ^ a b Yang, C. C. (1998). "Neuroanatomy of the penile portion of the human dorsal nerve of the penis". British Journal of Urology. 82 (1): 109–13. doi:10.1046/j.1464-410x.1998.00669.x. PMID 9698671. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help)
Retrieved from "https://en.wikipedia.org/w/index.php?title=Glans_penis&oldid=364036780"