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Anal and Bulbocavernous reflex

Anal reflex
Elicited by scratching the perianal skin and contraction of external anal sphincter is checked.The contraction can be felt with the finger inserted into the anal canal.

Root value of anal reflex
S3, S4. S5
Bulbocavernosus Reflex

This reflex is elicited by pinching the glans penis or pulling the catheter with the other hand placed over the perineum at the root of penis. This will produce reflex contraction of bulbospongiosus muscle.

Significance of bulbocavernous reflex
This reflex is useful  to differentiate between UMN and LMN bladder:
In UMN bladder reflex is  preserved
In LMN bladder reflex is lost.