Colorectal Surgery

Anal Fissure

An anal fissure is a painful anoderm tear, usually posterior midline; relieve constipation and sphincter spasm, and investigate atypical or refractory disease for secondary causes.

Definition

An anal fissure is a linear tear in the anoderm, usually in the posterior midline, causing marked pain during or after defecation and bright-red bleeding.

First principles

Pain and sphincter spasm perpetuate the tear

A tear causes pain, reflex internal-sphincter spasm and reduced anodermal perfusion. Hard stool and repeated trauma prevent healing; stool-softening and sphincter relaxation break the cycle.

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