Pelvic masses refer to abnormal growths or enlargements within the hip area, which can include tumors, cysts, fibroids, or abscesses. These masses can be either benign (non-cancerous) or malignant (cancerous), impacting health by causing symptoms such as pain, reduced mobility, and changes in bladder or bowel function, along with nerve-related issues like leg weakness.
Recently, a patient suffering from persistent pelvic pain and difficulty walking was referred to the 3DQ Lab for advanced imaging of a malignant mass located on the left side of the pelvis. The mass was identified as chondrosarcoma, a type of cancer that affects the cartilage cells of the body, which are the connective tissue found in many areas including joints, ribs, and between bones. Due to the complexity and specific location of the mass, a left internal hemipelvectomy—a surgical procedure aimed at removing the mass while preserving the lower limb—was planned. To aid in the surgical planning, a 3D-printed model of the pelvis and mass was produced, providing a physical reference for the surgical team.
Figure A: Horizontal rotational volume render of the pelvis (brown & white) and the mass (green).
Figure B: Vertical rotational volume render of the pelvis (brown & white) and the mass (green).
CT and MRI scans were obtained to map the tumor’s size, shape, and proximity to surrounding structures, such as the pelvic bone, blood vessels, and soft tissues. Using these images, a technologist segmented the pelvis and tumor under the guidance of a radiologist, ensuring accuracy of the tumor and its anatomical relationships. This segmentation formed the basis for creating a detailed 3D-printed model to aid in surgical planning.
Figure C: Axial MR scan showing the segmentation of the pelvis (magenta) and mass (light blue).
Below are pictures of the fully assembled 3D printed model.
Figure E: Anterior photo of the completed and assembled 3D print.
Figure F: Posterior photo of the completed and assembled 3D print.
Post-operative imaging of the hip was performed to assess its condition following the extensive surgical removal of the pelvic mass. The observed changes in the imaging are consistent with those typically seen after such a surgery. Additionally, a bilateral runoff study was conducted to evaluate the blood flow through the vessels in both lower extremities, which was determined to be satisfactory.
Figure G (Right): Volume rendering of the post-operation imaging.
