Penis & scrotum


Os penis

Topic Completed: 1 February 2010

Minor changes: 28 October 2020

Copyright: 2002-2021,, Inc.

PubMed Search: Os penis[TIAB]

Alcides Chaux, M.D.
Antonio L. Cubilla, M.D.
Page views in 2020: 334
Page views in 2021 to date: 296
Cite this page: Chaux A, Cubilla AL. Os penis. website. Accessed October 21st, 2021.
Definition / general
  • Heterotopic bone in penis (Eur Urol 1984;10:420), most commonly in elderly and also children
  • Note: male mammals except chimpanzees and humans have an intrapenile bone (bacula); humans have an equivalent strong distal ligament composed of type I collagen in the glans (J Androl 2005;26:624)
  • Also called baculum, penis / penile bone
  • Penile ossification may occur after trauma (Urology 1990;35:349)
  • Also associated with diabetes, gout, venereal disease, Peyronie disease and neoplasia
  • Rarely congenital (J Urol 1964;91:663)
Clinical images

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Figure F: obvious distal ligament within the glans penis

Microscopic (histologic) images

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Figure C: distal ligament

Differential diagnosis
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