Utility of 3D-Printed Models in the Surgical Planning for Primary Spine Tumors: A Survey of International Spinal Oncology Experts

Abstract

Study DesignSurvey study.ObjectivesThe purpose of this study was to characterize the utility of 3D printed patient specific anatomic models for the planning of complex primary spine tumor surgeries.MethodsA survey of individual members of an international study group of spinal oncology surgeons was performed. Participants were provided a clinical vignette, pathologic diagnosis, and pre-operative imaging for three primary spinal oncology cases. Study participants provided a free text surgical plan for resection and were then presented an associated 3D printed model for each case and asked to re-evaluate their surgical plan.ResultsTen spinal oncology surgeons participated in the study, representing nine institutions across five countries. Four of the surgeons (40%) made significant changes to their surgical plan after reviewing the 3D models, including sacrifice of an additional nerve root to obtain negative margins, sparing an SI joint that was originally planned for inclusion in the en bloc resection, adjusting the location of osteotomy cuts, changes to the number of surgical stages and/or staging order, and preservation of neurology that was originally planned for sacrifice. The overall impression of the 3D models was positive, with 90% of the participants stating they found the 3D model useful in developing a surgical plan.ConclusionsSurgical planning for resection of primary spinal column tumors is challenging and time intensive. 3D printed patient specific surgical models may be an additional tool that can augment surgical planning and execution by improving the chance of accomplishing surgical resection goals and minimizing morbidity.

Keywords: 3D model; 3D printing; primary spine tumor; spinal oncology; spine surgery; survey.

Figure 1.

AP (A) and lateral (B) x-rays of the lumbar spine depicting a left sided spinopelvic chondrosarcoma involving the left sided sacrum, SI joint, pelvis, and extending cephalad to L3 (arrows). T2 fat-saturated MRI demonstrates the T2 hypointense mass with a T2 hyperintense cartilaginous cap on coronal (C) and sagittal (D) images.

Figure 2.

3D model provided to study participants depicting a left sided spinopelvic chondrosarcoma.

Figure 3.

Sagittal CT (A, B), sagittal fat-saturated MRI (C), and axial T2-weighted MRI (D) demonstrate a right sided calcified mass with a cartilaginous cap extending from T4 to T8 with extension through the 6th and 7th ribs into the chest wall (arrows) consistent with a chondrosarcoma.

Figure 4.

3D model provided to study participants depicting a right sided thoracic chondrosarcoma.

Figure 5.

Sagittal (A) and axial (B) CT demonstrate a non-calcified destructive lytic mass from C5 to T4 (arrows) with posterior element involvement and extension into the right sided pedicles and facets. Contrast enhanced sagittal (C) and axial (D) MRI images demonstrate the soft tissue mass (arrows) eccentric to the right side with posterior element involvement. Biopsy was consistent with a malignant peripheral nerve sheath tumor.

Figure 6.

3D model provided to study participants depicting a right sided cervicothoracic malignant peripheral nerve sheath tumor.