There are five primary modes of endoprosthetic failure, and their relative incidences are significantly different and dependent on anatomic location. Mode of failure and time to failure also show a significant dependence. Because of these relationships, cumulative reporting of segmental failures should be avoided because anatomy-specific trends will be missed. Endoprosthetic design improvements should address failure modes specific to the anatomic location.

Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Central conventional CS with low/intermediate grade has a good prognosis, while high-grade tumors have poor outcome. Tumor relapses are strictly related with histologic grade.