The arcus tendineus levator ani (ATLA) is a thickened band of the obturator internus fascia running from the posterior surface of the pubic body anteriorly to the ischial spine posteriorly. It provides the primary origin of the levator ani muscle (specifically the pubococcygeus and iliococcygeus). It also supports the lateral vaginal wall as the arcus tendineus fasciae pelvis runs alongside it.
Forms the lateral attachment and origin of the levator ani muscle, providing the lateral pelvic floor foundation. Supports the lateral vaginal walls through its fascial condensation and anchors the pelvic floor to the lateral pelvic wall.
The ATLA is the landmark for paravaginal defect repair in pelvic reconstructive surgery. Lateral defect cystocele results from detachment of the vaginal wall from the ATLA, allowing the lateral bladder to prolapse medially — the opposite of central defect cystocele where the midline vaginal fascia attenuates. Paravaginal repair reattaches the vaginal wall to the ATLA either abdominally or laparoscopically. In sacrocolpopexy, sutures are placed at the level of the ATLA for lateral mesh attachment.
Lateral detachment of the pubocervical fascia from the arcus tendineus levator ani produces a paravaginal cystocele with anterior vaginal wall descent on the affected side, identified by seeing the lateral vaginal sulcus flatten when the examiner elevates it with a finger at the ATLA level, repaired by paravaginal repair reattaching the fascia to the arcus.
