The objectives of this video include to describe the anatomic relationship of the sacrospinous ligament to its surrounding vasculature, musculature, and nerves, to demonstrate the surgical procedures for extraperitoneal copepexy to the sacrospinous ligament with vaginal mesh, and finally, to review complications which may occur after the surgery. The sacrospinous ligaments are triangular-shaped, dense connective tissues which contribute to the stability of the bony pelvis. The broader base originates from the sacrum and narrows as it attaches to the ischial spine. In cadaveric studies, the average length of the sacrospinous ligament was 53.7 mm. The internal pudendal and inferior gluteal vessels, sciatic and pudendal nerves all pass through the greater sciatic foramen and in close proximity to the ischial spine and sacrospinous ligament. As a result, it is important that surgeons performing sacrospinous ligament suspensions are familiar with the neurovascular structures. Central to or overlying the sacrospinous ligament is the coccygeus muscle. Because it shares the same origin and insertion points as the sacrospinous ligament, some call these two structures as the coccygeus-sacrospinous ligament complex. The closest nerve structure to the sacrospinous ligament is the third sacral nerve, or S3, with a median distance of 3 mm superior to the border of the sacrospinous ligament at the midpoint. The fourth sacral nerve can be found coursing through the medial portion of the coccygeus muscle. The pudendal nerve is formed from the S2, S3, and S4 nerve roots. It courses parallel over the superior border of the coccygeus-sacrospinous ligament complex towards the greater sciatic foramen, then wraps medially around the ischial spine as it exits the lesser sciatic foramen. The pudendal nerve is the closest neurovascular structure to the tip of the ischial spine with a median distance of 0 mm and a range of 0-8 mm. Entrapment of the pudendal nerve typically presents with perineal paresthesia, or pain. The inferior gluteal artery most commonly originates from the anterior division of the internal iliac artery. It travels between the coccygeus muscle and the piriformis muscle as it exits through the greater sciatic foramen. The internal pudendal artery also originates from the anterior division of the internal iliac artery. Close to 90% of the time, it travels directly behind the ischial spine as it exits the greater sciatic foramen. With the relationship of the neurovascular structures around the ischial spine and the coccygeus-sacrospinous ligament complex, we recommend placing the sutures roughly 2-3 cm or 1.5 finger breadth medial to the ischial spine to reduce the risk of injuring the pudendal neurovasculature or the S4 nerve. We recommend placement of sutures 0.5 cm below the superior edge to reduce the risk of injury the inferior gluteal artery or S3 nerve. In the next portion of the video, we demonstrate the surgical technique for the treatment of pelvic organ prolapse using an extraperitoneal approach with sacrospinous ligament apical suspension with graft augmentation. The anterior vaginal wall is inspected and the bladder neck is identified. An Alice clamp is placed at the level of the bladder neck at the midline, with two additional clamps placed more proximally and laterally to form an inverted U-shaped incision. The area is infiltrated with dilute lidocaine with epinephrine, and the incision is made with a scalpel. Additional infiltration with normal saline can assist with the dissection in the vesicovaginal plane. Using male scissors, a full thickness layer of the vaginal epithelium is dissected off of the underlying fibromuscular layer. In patients with a cervix and uterus, the most proximal border for the initial dissection is the cervix. If there is a prominent cyst to seal, an anterior repair should be performed first by placating the vaginal muscularis and aventitia with imbricating sutures. Once vaginal entry is made, a combination of sharp and blunt dissection is performed to open the pararectal space. This is achieved with the use of the index finger with blunt dissection from the lateral to medial direction towards the ischial spine. The suture is loaded onto the CAPIO suture capturing device. Prior to placing the suture, the landmarks for placement, including the location of the ischial spine and the inferior and superior edges of the ligament, is confirmed. The CAPIO device is placed in the middle and inferior portion of the sacrospinous ligament roughly one and a half finger breaths from the ischial spine. After placement of the sutures through the sacrospinous ligament, a rectal exam is performed to ensure that there are no sutures in the rectum. The same procedure is performed bilaterally. To better understand the anatomic relationship of the sutures placed on the sacrospinous ligament, here we demonstrate the placement of the left arm of the mesh with a transabdominal retropubic view of the pelvic anatomy in a fresh frozen cadaver. First, the retropubic space is entered by performing a churning incision by transecting the insertion of the rectus abdominis muscles off of the pubic symphysis. The bladder is then bluntly dissected down to reveal the retropubic space. In this cadaver, the following structures were identified. The pubic tubercle, Cooper's ligament, aberrant obturator vein, obturator neurovascular bundle, ischial spine, arcus tendineus fascia pelvis with obturator internus muscle and iliococcygeus muscle. With concomitant vaginal dissection, one can see the process of the coccygeus sacrospinous ligament being cleared off. Prior to introducing the CAPIO device, the surgeon confirms the location of the ischial spine. It aims to be one and a half finger breaths lateral to the spine and on the lower half of the coccygeus sacrospinous ligament complex. After the suture is deployed, the CAPIO device is removed and tensioning on the suture confirms a strong placement. Next, after both arms have been deployed into the coccygeus sacrospinous ligament, both arms are pulled through until the mesh is flat against the vaginal muscularis. The new apex is defined by suturing the most proximal portion of the mesh through and through the vaginal epithelium of the apex. Next, the mesh is fixed distally at the level of the bladder neck in the midline as well as laterally with interrupted sutures of 2-OPDS. In patients with a cervix, the mesh is attached to the cervical parenchyma and paracervical fascia. Once the mesh is attached, the arms of the mesh are pulled through the sacrospinous ligament. In the cadaver retropubic abdominal view, the mesh arms are pulled through the sacrospinous ligament and the plastic sheets are removed. Finally, the area is copiously irrigated with bacitracin-containing solution. The vaginal submuscularis is first approximated with suture, the excess vaginal epithelium is trimmed, and a second layer of imbricating suture is used to close the vaginal epithelium. A cystoscopy is recommended after this procedure to evaluate for iatrogenic bladder injuries or ureteral kinks. Complications after sacrospinous ligament suspension include hemorrhage and neurologic pain. Hemorrhage requiring blood transfusion has an incidence of 2-8% depending on the type of ligature carrier used. Neurologic pain, defined as acute onset pain involving the buttock, groin, or lower extremity has an incidence of 12-15%. In summary, to reduce complications associated with this procedure, we recommend placing the sutures roughly 2-3 cm or 1.5 finger-breadths medial to the ischial spine and roughly half a centimeter below the superior edge. A thorough understanding of the neurovasculature around the sacrospinous ligament is needed to reduce adverse events.

sacrospinous ligament

anatomic relationship

pelvic stability

ligament suspensions

neurovascular structures