Organ
Male urethra
A shared outlet through prostate, perineum and penis
High-yield
From proximal to distal: preprostatic, prostatic, membranous and spongy regions. The prostatic portion is relatively capacious; the external meatus is usually the narrowest opening.
Overview
The male urethra extends from bladder neck to the meatus in the glans and carries urine or semen at different times. It passes through regions with different surrounding tissues, caliber and mobility. Four-part and three-part classifications differ mainly in whether the short preprostatic region is counted separately.
Reference facts
- Location
- Runs from the bladder through prostate and perineal region, then within corpus spongiosum to the glans; total adult length is often around 18–20 cm but varies.
- Parts
- Preprostatic, prostatic, membranous and spongy regions; the spongy segment includes bulbar and penile portions and the distal navicular fossa.
- Blood supply
- Prostatic/vesical branches supply proximal regions, while internal pudendal urethral and bulbar branches supply much of the distal course.
- Innervation
- Pelvic autonomic plexuses serve proximal smooth muscle and glands; pudendal sensory and somatic motor branches contribute distally and to the striated sphincter.
- Venous/Lymphatic drainage
- Veins communicate with pelvic and penile venous channels. Posterior urethral lymph favors pelvic nodes; anterior urethral lymph reaches superficial/deep inguinal and subsequently pelvic groups.
- Relations
- Passes within the prostate, through the sphincter complex and along the ventral erectile body; its curvature and distensibility change along this route.
- Function
- Carries urine during voiding and conveys semen entering through reproductive ducts during ejaculation.
Mnemonic
Trace the route: before prostate, within prostate, across the membrane, then through spongiosum.
Clinical correlation
Blunt perineal straddle trauma particularly threatens the bulbar segment; pelvic-ring disruption more often injures the posterior urethral region. The distribution of blood or urine depends on which fascial layers are torn, rather than following one obligatory pattern.
Frequently asked questions
Where is the male urethra located?
Runs from the bladder through prostate and perineal region, then within corpus spongiosum to the glans; total adult length is often around 18–20 cm but varies.
What does the male urethra do?
Carries urine during voiding and conveys semen entering through reproductive ducts during ejaculation.
What are the parts of the male urethra?
Preprostatic, prostatic, membranous and spongy regions; the spongy segment includes bulbar and penile portions and the distal navicular fossa.
What is the blood supply of the male urethra?
Prostatic/vesical branches supply proximal regions, while internal pudendal urethral and bulbar branches supply much of the distal course.