EP746 - Sacrococcygeal Hernia Following Tailgut Cyst Resection Requiring Mesh and Bilateral Gluteal Flap Reconstruction: A Case Report

Purpose/Background: Posterior approaches (Kraske) provide excellent exposure for low presacral lesions but are associated with a spectrum of risks. A sacrococcygeal hernia following presacral tumor resection with coccygectomy is exceedingly rare but described in isolated case reports. We describe a patient with a sacrococcygeal hernia following presacral mass resection and partial coccygectomy who was managed with mesh reconstruction and local vascularized tissue coverage to repair the posterior pelvic defect and weakness.

Methods/Interventions: A 74-year-old woman with hypertension and hypothyroidism presented with bloating, diarrhea, and urgency. Digital rectal exam demonstrated an extrinsic smooth fullness posteriorly, with the ability to palpate the proximal extent of a presacral lesion. Colonoscopy was without mucosal abnormalities. An MRI of the pelvis confirmed a cystic presacral mass, separate from the muscular rectal wall. It is located below the S4 level, effacing the levators without discrete invasion, and contains no solid components. There is no suspicious regional adenopathy. This was presumed to represent a tailgut or duplication cyst, for which biopsy was deferred and resection recommended through a posterior Kraske approach with partial coccygectomy due to the proximal extent of the lesion extending to the level of the coccyx.

The patient underwent a posterior Kraske approach resection with en bloc coccygectomy through a midline sacral incision. To provide exposure for resection, the coccyx and S5 were transected using intraoperative X-ray guidance. The lesion was multi-cystic and broadly effacing the rectal wall once exposed. The soft tissue was closed in multiple layers. The patient initially recovered uneventfully, and a complete excision of a 2.5 cm benign tailgut cyst was confirmed pathologically.

Approximately 2 years following resection, the patient presented with progressive severe tailbone pain. CT and MRI imaging at this time showed sigmoid colon prolapse into the sacrococcygeal defect. Physical examination was consistent with a reducible midline posterior hernia without skin changes. The patient was maintaining baseline bowel and urinary function.

Results/Outcomes: The patient underwent an open sacrococcygeal hernia reduction, repair with a Ventralight ST Mesh, and a bilateral gluteal fasciocutaneous rotational flap reconstruction. The Ventralight ST Mesh was secured over the 5-cm hernia defect to the surrounding tissue and periosteum. Recovery was uneventful except for a superficial wound dehiscence managed conservatively. At the 6-month follow-up, she remained pain-free with preserved bowel and urinary function as well as no radiographic recurrence of the mass.

Conclusion/Discussion: Tailgut cyst excision via posterior Kraske approach with coccygectomy can rarely result in a sacrococcygeal hernia through a posterior pelvic floor defect and weakened meso-rectal barrier. We describe hernia repair with mesh and rotational flap soft tissue reconstruction to address this delayed symptomatic complication.

Sacrococcygeal Hernia Following Tailgut Cyst Resection
A sacrococcygeal hernia that was reducible, midline posterior, without skin changes.
Sagittal CT of Pelvis of a Sacrococcygeal Hernia
Sagittal CT scan of pelvis 20 months after the initial surgery, showing sacrococcygeal hernia just under S4 pushing into subcutaneous tissue with the patient lying flat.