Evaluating MUTARS®
mega-endoprostheses 

Background

At present, limb-sparing tumor resection is the mainstay of treatment for primary malignant bone tumors. Reconstruction of these commonly large bone defects are associated with frequent complications, including (aseptic) loosening, implant failure, and prosthetic joint infections. Aiming for a durable modular implant system, the Modular Universal Tumor And Revision System (MUTARS®) was introduced in 1991. Since then, the system has been used both in the reconstruction of tumor-related bone defects and increasingly in revision endoprosthesis of all major joints. However, compared with primary endoprosthesis, the total number of implanted modular endoprosthesis and their follow-up are limited. It is therefore particularly unfortunate that tumor or mega prostheses are not included in (international) implant registries. From an international collaborative initiative, we now aim to develop an international multicenter cohort study for these large endoprostheses specifically.

Aims

To perform a qualitative evaluation of MUTARS® endoprostheses survival, to describe failure types and mechanical and non-mechanical complications (according to the Henderson classification), and to describe risk factors for complications. At last, one of the aims is to evaluate the functional outcome of patients after being reconstructed with MUTARS® endoprostheses.

Project Outcomes

• Evenhuis RE, Acem I, Rueten-Budde AJ, Karis DSA, Fiocco M, Dorleijn DMJ, Speetjens FM, Anninga J, Gelderblom H & van de Sande MAJ (2021). Survival Analysis of 3 Different Age Groups and Prognostic Factors among 402 Patients with Skeletal High-Grade Osteosarcoma. Real World Data from a Single Tertiary Sarcoma Center. Cancers, 13(3):486. doi: 10.3390/cancers13030486

Team

• Dr. M.P.A. Bus, Department of Orthopaedic Surgery Leiden University Medical Centre

• Drs. R. Evenhuis, PhD candidate at the Department of Orthopaedic Surgery of Leiden University Medical Centre

• Prof.dr. M. Fiocco, Mathematical Institute Leiden University, Department of Biomedical Data Sciences Leiden University Medical Center & Princess Máxima Center for Pediatric Oncology 

• Prof.dr. M.A.J. van de Sande, Department of Orthopaedic Surgery Leiden University Medical Centre & Princess Máxima Center for Pediatric Oncology