Five-year-old Daria loves dancing, but that was imperiled when she was diagnosed with Ewing’s Sarcoma, a rare malignant bone tumor, in her right leg. The tumor was large, extending almost to her distal femur, so removing it while still allowing her to walk – and dance – normally was a special challenge. Careful planning was required, but thankfully, Daria’s doctors had the tools to do just that.
“With all the soft tissues and skin in the way, what surgeons experience in surgery can be completely different to what they see on a 2D scan,” said Mieke Motmans, Clinical Engineer at Materialise. “Using 3D digital and physical models gives an extra level of information and to work out exactly how best to proceed – it’s like the difference between outlining a journey on a paper map, and using a GPS that tells you exactly where you are going and when you will get there.”
Dr. A.H. Krieg and colleagues at the University Children’s Hospital in Basel, Switzerland had to remove the tumor and reconstruct Daria’s femur using a combination of her own live fibula and a donor bone.
“Endoprostheses (artificial bones) are the usual limb-salvage treatment if the tumor is close to the knee joint or extends to the epiphysis, but this is rarely possible for children as young as Daria – there are high complication rates,” said Dr. Krieg. “Making the reconstruction a success meant using 3D printing to its full potential and working with the right experts.”
Materialise has worked with surgeons to plan for more than 2,000 osteotomy cases, or corrective surgery where a bone is cut to allow realignment. The company has also designed and 3D printed more than 700 custom implants or endoprostheses.
“I’d actually worked with Mieke and her team before, so I knew they could help,” said Dr. Krieg. “The first step was uploading our MRI and CT scans of Daria’s leg to Materialise’s online portal for evaluation.”
Motmans specializes in oncology cases. Her team began by aligning meshes from Daria’s CT and MR scans, checking them in the Materialise Mimics medical imaging processing software and verifying the tumor’s position.
Image Credit: Materialise