Micturition

Question 1

What prevents reflux of urine during micturition?

Answer 1

Vesicoureteral valve

Question 2

What structures support the bladder?

Answer 2

Pubovesical ligament (female)
Puboprostatic ligament (male)
Levator Ani

Question 3

What kind of activity is micturition?

Answer 3

A reflex activity that we learn to suppress via the CNS

Question 4

What is the sensory innervation of the bladder?

Answer 4

T12-L2 with Sympathetic (upper bladder with peritoneum)

S2-4 with Parasympathetic (lower bladder without peritoneum)

Question 5

Describe the nervous pathway of sense of needing to urinate

Answer 5

1. Autonomic fibres travel to pelvic organ via inferior hypogastric plexus
2. Sensation of fullness (around 400mls) conveyed via visceral afferents (mainly with parasympathetic) to micturition centres (sacral spinal cord)