Abstract
Background
A variety of cerclage systems are available for the fixation of periprosthetic fractures. The aim of this study was to compare the forces applied by these systems.
Methods
We designed and manufactured a device to measure the forces applied to a cylindrical structure by a cerclage cable. Five different commonly used systems were evaluated. The forces exerted were measured at four different locations on the cylinder and this was compared to the force indicated by the tensioning device.
Results
Only one of the devices consistently indicated the correct force. Some of the cables became frayed after being used more than twice. There was a pattern of increase in force closer to the point of crossing of the cables.
Conclusion and Clinical Relevance
The true force applied to the bone is not reflected by the value indicated by the tensioning device. Some cables should not be retensioned more than twice. The device connecting the cable should be placed on the strongest part of the bone as this is the area where the maximum force is exerted
NO DISCLOSURES
