Reconstruction after Subtotal Sacrectomy for Sacral Ewing's Sarcoma Using Tibial Allograft Strut Grafting: A Case Report

Abstract

We present the case of a 15-year-old girl. Two months after becoming aware of pain, she was diagnosed with a sacral tumor and referred to our department. She was diagnosed with a sacral Ewing's sarcoma; after chemotherapy, it was determined that the tumor could be resected, so surgical treatment was performed. The sacrum and ilium were partially resected at the lower end of S1, and the lumbar vertebrae and pelvis were fixed with a pedicle screw and two iliac screws on each side of L3, and the sacral resection was reconstructed with a tibial strut allograft. No tumor recurrence or metastasis has been observed 1 year postoperatively. She developed bladder and rectal dysfunction, but she remained independent in activities of daily living and her daily life was not limited. The bone fusion in the reconstructed area confirmed the lack of instrumentation looseness. Surgical treatment for sacral Ewing's sarcoma was performed to cure the patient. We believe that the tibial allograft contributed to the patient's ability to walk on her own due to its high mechanical stability. Postoperative bone healing was observed with the same material, suggesting that the tibial allograft is useful for similar procedures.

Keywords: Ewing's sarcoma; Reconstruction; Subtotal sacrectomy; Tibial allograft.

Fig. 1

Radiograph of the pelvis (A), computed tomography in the coronal plane (B), and magnetic resonance imaging in the coronal plane (C) and in the axial plane (D). A destructive lesion on the right side of the S2 sacrum with no calcification was observed (yellow arrows).

Fig. 2

Histopathological examination (A) and immunohistochemical analysis (B). Fluorescence in situ hybridization (C, D) showed an ESWR1 split signal in 54% and an FLI1 split signal in 56%.

Fig. 3

Computed tomography (A) and magnetic resonance imaging of the pelvis (B) after neoadjuvant chemotherapy. Neoadjuvant chemotherapy caused 73% tumor shrinkage. We performed extensive pelvic resection and reconstruction using tibial allograft strut grafting with double posterior rod instrumentation (C–E).

Fig. 4

Postoperative radiographs (A, B) and computed tomography images (C–E) of the pelvis. There was no osteolysis of the reconstructed area and no implant failure.