There has been much debate about the causes of primary anal fissures. Historically, the eliciting factor was considered to be the trauma resulting from the passage of hard feces, but less than 25% of the cases of chronic anal fissures are associated with constipation. Furthermore, many anal fissures of traumatic origin heal whereas others do not. For many years an association with internal anal sphincter (IAS) hypertonia has been evident, although in elderly patients  and in postpartum patients cases of anal fissure have been reported that are associated with a normal or hypotonic IAS. The basal tone of the IAS is affected by various substances, including nitric oxide (NO) . In patients with anal fissures, the synthesis of NO in the IAS is reduced in comparison with the controls . Manometry studies have demonstrated an increased IAS tone and a reduction in anodermal vascular blood flow, mainly in the posterior region  and showed that in patients who benefited from sphincterotomy surgery or from anal stretch sphincter hypertonia was reduced and blood flow increased. This pathogenetic mechanism can explain the achievement of a high rate of healing with medical therapies able to improve blood flow and/or to reduce hypertonia. Triamcinolone injection has been used effectively in levator syndrome and in chronic perianal wounds. Chronic fissure patients present with painful defecation and increase in sphincter tone leading to vicious cycle preventing healing of the fissure in ano. Lateral sphincterotomy which is the gold standard treatment for chronic fissure in ano may lead to post operative complications in the form of hematoma, abscess, fistula and complications of anaesthesia eg. urinary retention. Triamcinolone steroid injection will reduce the inflammation and help in wound healing.

This study will focus on the short and/or long term outcomes following LIS and local triamcinolone injection in chronic fissure in ano.