Diagnosis and Examination of Anal Fissures

Diagnostic Approach

Anal fissures are best visualized by effacing the anal canal with opposing traction on the buttocks, not through digital rectal examination, as recommended by the American Gastroenterological Association 1
Digital rectal examination may actually be contraindicated in suspected anal fissures due to the severe pain it can cause, according to the World Journal of Emergency Surgery 2, 1
Fissures are splits in the squamous epithelium at or just inside the anal verge, making them visible on external examination, as noted by the American Gastroenterological Association 1
Most fissures (90%) are located posteriorly in the midline, with anterior fissures occurring in 10% of women versus 1% of men, as reported by the World Journal of Emergency Surgery 3

Chronic fissures may have associated findings that can be visualized, including a sentinel skin tag just distal to the fissure, hypertrophied anal papilla at the proximal margin, and fibrosis and visualization of bare internal sphincter muscle at the fissure base, as described by the American Gastroenterological Association 1

In cases of severe pain, instrumentation of the anal canal is inappropriate and traumatic, as stated by the American Gastroenterological Association 1
When significant anal pain prevents proper examination, examination under anesthesia may be warranted, according to the American Gastroenterological Association and the World Journal of Emergency Surgery 1, 2
Anal pain is often mistakenly attributed to hemorrhoids when it may actually be due to anal fissure, perianal abscess, or anal fistula, as noted by the American Gastroenterological Association and the World Journal of Emergency Surgery 4, 5

Imaging is not typically needed for diagnosis of typical anal fissures, but may be warranted in atypical presentations to rule out occult perianal sepsis, complex anal fistula, underlying inflammatory bowel disease, or anal or colorectal cancer, as recommended by the World Journal of Emergency Surgery 3, 2

The diagnosis of anal fissure should be suspected based on history alone, including anal pain during and after defecation, and scanty bright red bleeding, as suggested by the American Gastroenterological Association 1
Approximately 20% of patients with hemorrhoids have concomitant anal fissures, highlighting the importance of thorough visual examination, as reported by the American Gastroenterological Association 4