Male Urethra
Definition
o A canal extending from the neck of the bladder to the exterior at the external urethral orifice
o In the male the urethra is associated with the urinary and the reproductive systems
The male urethra
o A common pathway for the flow of urine and semen, the combined secretions of the
male reproductive organs
o 20 cm
Parts
o Prostatic urethra - the part within the prostate
o Membranous urethra - the part within the urogenital diaphragm the part between the prostate and the bulb of urethra -
o Bulbar urethra - the part within the bulb of the penis
o Penile urethra - the part in the shaft of penis
o Glandular urethra - the part within the glans penis
Sphincters
o Internal sphincters - smooth muscle - at the neck of the bladder
o External sphincter - striated muscle - surrounding the membranous part
Structure
o Muscle layer
o Continuous with that of the bladder
o At the origin - internal urethral sphincter
o In the middle third there is striated muscle surrounding the urethra - external
urethral sphincter
o Submucous spongy layer - blood vessels and nerves
o Mucous membrane lining - continues from bladder - lower part stratified squamous epithelium
Applied Anatomy
- Benign Prostatic Hypertrophy - narrowing of the prostatic urethra - obstruction to the flow of urine - urinary retention - residual urine
- Penile urethra - gonorrhoea - stricture of the urethra
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