A rare case of Ewing's sarcoma in a 4-year-old child treated by tumor endoprosthetics using 3D printing

Abstract

Orthopedic oncology surgery often requires, by its very nature, precise and often extensive resections of bone and soft tissue involved in or near the tumor mass.
 One of the most recent and promising innovations is represented by 3D printing technology, whose main advantage in this field of application is patient specificity, which is essential in an operation that requires high precision and maximum respect for the individuality of his bones and soft tissues.
 Material and methods: In the present report, we present a 4-year-old boy diagnosed with Ewing's sarcoma involving ¾ of the right tibia. In another medical facility, he was offered amputation. Our team decided to use the "3D printed tumor megaendoprosthesis, double growing, from the Czech company Prospon. For reinsertion of the muscle groups to the endoprosthesis, we used a LARS textile tube that was attached to the femoral and tibial components of the endoprosthesis. A vascular surgeon also participated in the team. The patellar ligament was reinserted to the tibial component, and myoplasty was additionally performed with the medial head of the m. gastrocnemius. Intraoperatively, we lengthened the lower limb by 1.5 cm to delay the upcoming staged lengthening.
 Results: The postoperative period was uneventful, with sutures removed on the 12th postoperative day. For 3 weeks, a tutor orthosis was placed. Active physiotherapy was started after removal of the orthosis 21 days after surgery.
 Conclusion: Our goal is to perform a total revision at the end of skeletal growth if possible and replace the current implant with a non-growing tumor megaendoprosthesis in the absence of near or distant metastases and long-term patient survival.
 Future expectations are that non-invasive lengthening mechanisms or a biological approach will be able to meet the special needs of this population.