Cervical Stent Failure Analysis

摘要

Harrington rods failed after a short period in service. Metallurgical analysis showed (1) notches were present on the rods, (2) small cracks present in the bent regions of the rod, and (3) the fractures occurred at clamped locations. All of these conditions can shorten the fatigue life by eliminating the crack initiation stage of fatigue and allowing corrosion fatigue to occur.