Contralateral osteotomy of the pedicle and posterolateral elements for en bloc resection: a technique for oncological resection of posterolateral spinal tumors.

En bloc resection of tumors involving the spinal column is technically challenging and is associated with high morbidity to the patient due to the proximity of critical neurological and vascular structures and the destabilizing nature of this surgery. Nevertheless, evidence has shown improved progression-free survival with en bloc resection for certain low-grade malignant and aggressive benign musculoskeletal tumors. To avoid the morbidity of en bloc spondylectomy in patients with tumors localized to the lateral and posterolateral spinal column, the authors have found that the goals of surgery can be accomplished through a contralateral osteotomy of the pedicle and posterolateral elements for en bloc resection (COPPER). They reviewed their series of 5 patients who underwent successful tumor removal through a COPPER approach. These patients were all found to harbor spinal column tumors involving the posterolateral elements that, based on pathology, would benefit from en bloc resection. Tumor pathology included chondrosarcoma, leiomyosarcoma, osteoblastoma, and liposarcoma. Resections were performed by completing ipsilateral facetectomies above and below the lesion and ipsilateral pedicle osteotomies from a contralateral approach following hemilaminectomy. By disarticulating the posterolateral elements while carefully protecting the thecal sac, the tumors were removed en bloc along with the affected lamina, pedicles, pars interarticularis, and spinous processes, allowing tumor-free margins. This technical report suggests that the COPPER approach is safe and effective for en bloc resection of tumors involving the posterolateral aspect of the spinal column with tumor-free margins and that it eliminates the need for anterior column reconstruction.