The anococcygeal ligament is a fibromuscular band connecting the posterior external anal sphincter and the posterior perineal body to the coccyx and the distal sacrum. It forms part of the posterior wall of the ischiorectal fossa and provides posterior anchorage for the external anal sphincter complex. The posterior fibres of the levator ani (iliococcygeus) also contribute to this structure.
Anchors the posterior external anal sphincter to the coccyx, providing posterior pelvic floor fixity, and contributes to anal canal structural support during defaecation and pressure elevation.
The anococcygeal ligament is relevant in coccygodyne (coccyx pain) surgery, where it may be disrupted or fibrotic. In abdominoperineal resection for rectal cancer, the perineal dissection divides the anococcygeal ligament to complete posterior perineal dissection. Persistent coccygodyne after coccyx fracture or bruising from falls may involve the anococcygeal ligament insertion, treated by local injection or rarely by coccygectomy. The posterior perineal triangle dissection for perineal hernia repair uses the ligament as a posterior boundary reference.
Coccyx fracture or dislocation strains the anococcygeal ligament at its coccygeal insertion, producing chronic coccydynia reproduced by direct coccyx palpation and sitting on hard surfaces; local corticosteroid injection at the ligament insertion provides relief in the majority, with coccygectomy reserved for refractory cases.
