The cause of axial rotation of the scoliotic spine.
To explain the cause of axial rotation in a scoliotic vertebral column, the influence of the gravitation force on a spine with a C-scoliosis has been investigated by means of a mechanical model. In this model the gravitation force takes hold of the three-dimensionally curved vertebral column eccentrically. From these reflections it appears that the axial rotation in the scoliotic spine can be explained by the moment distribution caused by this eccentrical gravitation force. The moment distribution, necessary for correction of the spine, is supposed to be opposite to the moments caused by the gravitation force. The moment distribution caused by the Harrington and the Luque spinal correction systems are compared to the calculated optimum correction moments. It appears that the moment distribution for the Harrington and Luque methods, necessary for the correction of the lateral deviation, are almost the same as the calculated correction moments. But the axial rotation appears to be increasing instead of decreasing in both correction systems.
Treatment of scoliosis. Correction and internal fixation by spine instrumentation.
A new method for the treatment of scoliosis is described in which a metal system of rods and hooks is implanted, and distraction and compression forces applied, to correct the curve and stabilize the treated segments in the corrected position by skeletal fixation. The technique and principles of this method of treatment and a summary of the preliminary results obtained are given.
A slowly rotating coil system for AC field measurements of Fermilab Booster correctors
A method for measurement of rapidly changing magnetic fields has been developed and applied to the testing of new room temperature corrector packages designed for the Fermilab Booster Synchrotron. The method is based on fast digitization of a slowly rotating tangential coil probe, with analysis combining the measured coil voltages across a set of successive magnet current cycles. This paper presents results on the field quality measured for the normal and skew dipole, quadrupole, and sextupole elements in several of these corrector packages.