Penis and scrotum
Scrotum - normal

Authors: Antonio Cubilla, M.D., Alcides Chaux, M.D. (see Authors page)

Revised: 9 April 2018, last major update May 2010

Copyright: (c) 2002-2018,, Inc.

PubMed Search: Scrotum[TI] normal[TIAB]

Page views in 2018: 532
Page views in 2019 to date: 50
Cite this page: Cubilla, A., Chaux, A. Scrotum - normal. website. Accessed January 22nd, 2019.
Definition / general
  • Cutaneous fibromuscular sac containing testes, epididymis and distal spermatic cord
  • Derives from genital swellings or labioscrotal folds which enlarge and fuse in midline to form scrotal sac
  • Formation is mediated by 5 alpha dihydrotestosterone
Diagrams / tables

Images hosted on PathOut server:

Cross section of the scrotal wall

Images hosted on other servers:

Embryologic development

Anatomic layers
  • Skin: thin, corrugated and pigmented; includes keratinized squamous epithelium with skin adnexae, dermis and scattered adipocytes but no subcutaneous tissue; divided in half by a midline cutaneous raphe, which continues to inferior penile surface and along perineum to anus
  • Dartos muscular layer: two coherent plexuses of smooth muscle cells; contracts in cold or during sexual stimulation
  • External spermatic fascia (intercrural layer of Colles fascia): continuation of external oblique aponeurosis
  • Cremasteric muscle (cremasteric layer of Colles fascia): bundles of skeletal muscle, continuation of internal oblique muscle
  • Internal spermatic fascia (infundibuliform layer of Colles fascia): partitioned in the midline, continuation of transversalis fascia, attached to tunica vaginalis
  • Parietal layer of tunica vaginalis

Images hosted on other servers:

Various images

Inguinal ring

Clinical images

Images hosted on other servers:

Constricted human
scrotum (without
hair) with the raphe
clearly exposed

Microscopic (histologic) images

Images hosted on PathOut server:

Muscle bundles of the
dartos are beneath
the keratinized
squamous epithelium

Thick bundles of
conspicuous smooth
muscle in the deep
reticular dermis