Investigation of How Different Halos Influence Pin Forces

摘要

Study DesignThis study investigated the effect of the size and material of halo rings on the pin force produced at the halo pin-calvarium complex.Summary of Background DataLoosening of halo pins has been a problem with using the halo-vest apparatus to stabilize cervical spine fractures.MethodsOne standard halo pin and seven different halo rings were used to test the anterior pin hole of each ring at a constant torque of 8 inch-pounds (0.9 Nm).ResultsPin force fluctuated from halo to halo, and decreased as the nut was tightened.ConclusionsIdentical torques applied to different halos will not guarantee the same magnitude of pin force for halo fixation.