| Dartos fascia | |
|---|---|
 Thescrotum. (Label for dartos is at bottom left.) | |
 Thescrotum. (Label for dartos is at bottom left.) | |
| Details | |
| Origin | Subcutaneous tissue ofscrotum, superficial to superficial fascia (Colles) |
| Insertion | Skin and midline raphe ofscrotum |
| Nerve | Genital branch of genitofemoral nerve |
| Actions | Corrugates the scrotum |
| Identifiers | |
| Latin | tunica dartos |
| TA98 | A09.4.03.003 |
| TA2 | 3695 |
| FMA | 18088 |
| Anatomical terms of muscle | |
Thedartos fascia,dartos tunic or simplydartos is a layer ofconnective tissue found in thepenile shaft,foreskin andscrotum.[1] The penile portion is referred to as thesuperficial fascia of penis or thesubcutaneous tissue of penis,[2] 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 withColles' fascia of the perineum andScarpa's fascia of the abdomen.[1]
The dartos lies just below the skin, which places it just superficial to the external spermatic fascia in the scrotum and toBuck's fascia in the penile shaft. In the scrotum, it consists mostly ofsmooth muscle.[3] The tone of this smooth muscle is responsible for the wrinkled (rugose) appearance of the scrotum.[1] In females, the same muscle fibers are less well developed and termeddartos muliebris, lying beneath the skin of thelabia majora. The dartos fascia receives innervation frompostganglionic sympathetic nerve fibers arriving via theilioinguinal nerve and theposterior 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.[1] 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.[1]
In the scrotum, the dartos fascia acts to regulate thetemperature of thetesticles, which promotesspermatogenesis. It does this by expanding or contracting to wrinkle the scrotal skin.
The dartos muscle works in conjunction with thecremaster muscle to elevate thetestis but should not be confused with thecremasteric 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.
There is an increase in elastic fibers with increasing maturity that allows the foreskin to become retractable by adulthood and glide freely back and forth.
Etymology:
Some dartos-related terms:
