Causes and Risk Factors of Anal Fissure Anal fissures are most often caused by trauma to the anal canal, particularly during a hard or strained bowel movement. The tear usually forms in the posterior (back) midline of the anus, where blood flow is relatively lower — making it slower to heal. Below you can read more about the causes and risk factors of anal fissure. Common Causes: Risk Factors: In some cases, no obvious cause is found — these are called idiopathic fissures. Identifying and addressing the underlying cause, such as constipation or poor bowel habits, is essential to preventing recurrence. Let’s now look at how anal fissures are diagnosed and differentiated from other conditions. 👉 [Next: Diagnosis of Anal Fissure] Complications and Recovery from Constipation Treatment for Anal Fissure Anal Fissure Complications of Anal Fissure