The force exerted by the halo pin. A study comparing different halo systems.
Seven different halo systems were evaluated biomechanically to compare the force exerted by the halo pin in each system. In three different experiments torque values of 2, 4, 6, 7, and 8 in lb were applied to the halo pin, and the force at the skull end of the halo pin was measured using a load cell. In the first experiment, the threads on the halo pin were dry, in the second experiment saline was applied to the threads on the pin, and in the third experiment cadaveric bone from the skull was interposed between the pin and the load cell. The results showed that for a given value of applied torque to the pin, the force exerted by the pin end varied widely according to the halo system and whether or not the pin was "lubricated."
Whitesides
T E
TE
Department of Orthopaedics, Emory University School of Medicine, Decatur, Georgia.
Mehserle
W L
WL
Hutton
W C
WC
D000328:Adult; D001858:Bone Nails; D002102:Cadaver; D002574:Cervical Vertebrae; D016267:External Fixators; D006801:Humans; D008153:Lubrication; D008297:Male; D008875:Middle Aged; D012886:Skull; D012965:Sodium Chloride; D013314:Stress, Mechanical; D014143:Traction / Q000295:instrumentation*
D012965:Sodium Chloride