Description/Scope. This document addresses proposed indications for sacroiliac joint fusion, a surgical procedure which fuses the iliac bone (pelvis) to the spine (sacrum). It is performed for a variety of orthopedic conditions including trauma (with fracture), infection, cancer, and spinal instability.escription/Scope. This document addresses proposed indications for sacroiliac joint fusion, a surgical procedure which fuses the iliac bone (pelvis) to the spine (sacrum). It is performed for a variety of orthopedic conditions including trauma (with fracture), infection, cancer, and spinal instability.