Dartos: Difference between revisions

 

 

 

 

 

 

 

 

{Infobox muscle

| Name        = Dartos

| Latin      = Tunica dartos

| Image       = Gray1143.png

| Caption     = The [[scrotum]]. (Label for Dartos is at bottom left.)

| Image2     = Gray1144.png

| Caption2   = The [[scrotum]]. (Label for Dartos is at bottom left.)

| Origin     = Subcutaneous tissue of [[scrotum]], superficial to superficial fascia (Colles)

| Insertion   = Skin and midline raphé of [[scrotum]]

| Blood       = [[Artery of Duffy]]{{Citation needed|date=April 2011}}

| Nerve      = [[Genital branch of genitofemoral nerve]]

| Action      = Corrugates the scrotum

| Antagonist  =

author=Campbell | chapter= | editor=Alan J. Wein, editor | title=Campbell-Walsh Urology | publisher=Philadelphia: Elsevier Saunders | date= | isbn=978-1-4160-6911-9 | pages= }}</ref> The penile portion is referred to as the '''superficial fascia of penis''' or the '''subcutaneous tissue of penis''',<ref>[http://www.unifr.ch/ifaa/Public/EntryPage/TA98%20Tree/Entity%20TA98%20EN/09.4.01.027%20Entity%20TA98%20EN.htm Terminologica Anatomica 98]</ref> while the scrotal part is the dartos proper. In addition to being continuous with itself between the scrotum and the penis, it is also continuous with [[Colles fascia]] of the perineum and [[Scarpa's fascia]] of the abdomen.<ref name=Campbell10 />

 

It lies just below the skin, which places it just superficial to the external spermatic fascia in the scrotum and to [[Buck's fascia]] in the penile shaft.

 

In the scrotum, it consists mostly of smooth muscle.<ref>Gray's 16th Edition</ref> The tone of this smooth muscle is responsible for the wrinkled (rugose) appearance of the scrotum.<ref name=Campbell10 />

 

It receives innervation from postganglionic sympathetic nerve fibers arriving via the [[ilioinguinal nerve]] and the [[posterior scrotal nerves|posterior scrotal nerve]].

In the penis, the loose attachment of the dartos fascia to Buck's fascia is responsible for the high degree of mobility of the penile skin over the underlying tissue.<ref name=Campbell10 /> It is also responsible for carrying the blood supply of the penile skin, a longitudinally-coursing anastomotic network of vessels that arise from the external pudendal vessels.<ref name=Campbell10 />

In the scrotum, the tunica dartos acts to regulate the [[temperature]] of the [[testicle]]s, which promotes [[spermatogenesis]]. It does this by expanding or contracting to wrinkle the scrotal skin.

* Contraction reduces the [[area|surface area]] available for heat loss, thus reducing [[heat]] loss and warming the testicles.

The dartos muscle works in conjunction with the [[cremaster muscle]] to elevate the [[testis]] but should not be confused with the [[cremasteric reflex]].

The dartos fascia keeps the foreskin close to the glans penis throughout life. In infancy, the dartos fascia operates as a one-way check valve at the tip of the foreskin, allowing urine to pass out, but prohibiting the entry of foreign matter and pathogens.

: Derived from the Greek δέρνω/derno (beat, flog) and/or δέρμα/derma (skin), meaning "that which is skinned or flayed", possibly due to its appearance.<ref>http://www.dartmouth.edu/~humananatomy/resources/etymology/Abdominal_wall.htm</ref>

[[Category:Mammal reproductive system]]

[[Category:Fascia]]