The patient a Kurdish citizen came to the clinic 12-August-2021 complaining of LBP and right hip pain the last 45 days after performing proton beam therapy in Germany 06-January-2021 by 18-March-2021. The histology was of chordoma and positive to malignant cells, AE1/APC positive, S100 positive, EMA positive. MRI of the pelvis showing a huge chordoma destroying completely S2 and down fulfilling the pelvic cavity and destroying the sacrum.

On examination, the patient in agonizing pain, limping with exaggerated scoliotic stance. SLRS was 80 degrees right side with pain. There is only analgesia in right side of the perianal region. The patient when lying have no pain, but when standing suffer from this agonizing pain at the right hip area.

The patient sent for investigations, which done the same day showing the huge the huge chordoma with further enlargement of diameter and fulfilling the right sacral alia with fracture of this location, explain why in standing position he suffer this agonizing pain. There redness of the skin with hard consistency at the sacral area. This is due to proton beam therapy and the fear for no healing of the wound in case of attacking the tumor directly. The last tumor dimensions is 100X91X106 mm, which is larger from the previous studies. The dysplasia of the left femoral head is from childhood and the patient is living with it without complains. It could be that the pathologic fracture of the right sacral wing is either from further expansion of the rumor or osteonecrosis from proton beam therapy. It was decided not to attack the whole tumor in such situation because of the fear of dehiscence of the wound and it was decide to limit manipulation for partial resection of the tumor at the right sacral wing and proper fixation of the right sacroiliac joint with preservation of the right S1 and S2 roots.

The aim of surgery at this stage is to alleviate the severe pain when standing. Skeletonization of L5 lamina upper sacrum and the entire posterior upper iliac spine and the right wing of the sacrum. down to the exit of the right S1 root. This segment was mobile and inside the foramen of the right S1 root the tumor was seen.  Using the C-arm 2 Zimmer cannulated screws with washers to aid proper fixation and compression were applied one 6.5 mm  115 mm length and the other 80 mm length.  Check of the previously mobile area became fixed and compressed, Bone cement HVR was applied to the screws and directly to the right lateral wing of the sacrum. All steps were performed with the C-arm.

Routine closure of the wound. Smooth postoperative recovery. The power of the feet not affected. He was sent to the ward.

Too early now.

The chordoma must be operated first, then radiotherapy or proton beam therapy applied. It seems that the radiotherapy did not provide the expected positive result, instead the tumor continued to grow further and the right sacral wing was fractured either from continued growth or radionecrosis.

Here was the aim of surgery was to fuse the mobile segment to make the patient able to walk.