Inclusion Criteria:  Major patient Patient managed in the proctology department of Groupe hospitalier Paris Saint-Joseph for single posterior idiopathic fissures (anoplasty possible only in the context of non-infected posterior fissure) between January 1 and December 31, 2019 by fissurectomy alone or fissurectomy with anoplasty  Exclusion Criteria:  anterior or bipolar fissure infected fissure history of proctological surgery Crohn's disease HIV infection tubercular lesion validated by anatomopathology history of pelvic-perineal radiotherapy Tumor cells on histology fissurectomy +/- anoplasty associated with another proctological surgical procedure patient under guardianship or curatorship patient deprived of liberty patient under court protection Patient opposing the use of his data for this research