CD INSTRUMENTATION - A PROSPECTIVE-STUDY ON THE DEROTATIONAL EFFECT

Purpose of the study CD instrumentation has been presented as a system which is able to achieve a 3-dimensional correction of idiopathic sco liose, We performed a prospective study about the apex derotation foll owing CD instrumentation. Materials and methods 24 consecutive patient s with idiopathic scoliosis were included in this study, On pre- and p ostoperative CT scans the rotation angle relative to the sagittal plan e according to Aaro and Dahiborn (RA sag) were measured the pre- and p ostoperative changes were evaluated with paired T-tests together with the significance, Kruskal Wallis tests were performed to correlate the mean values of those calculated changes with the number of instrument ed levels and with the different King types of scoliosis. Results Ther e was no statistical significant increase or decrease of the rotation if we consider the sag without laking into account the type of curve. Discussion The different ways to measure rotation in scoliosis are pre sented, The limits of the method we used (RA sag) are also discussed. We reviewed the literature concerning derotation with CD instrumentati on to compare it with our results. Conclusion The evaluation of rotati on in scoliosis is not easy, The CT scan seems to be the best method. Nevertheless, the postoperative changes of the morphology of the patie nt can be a factor of error in rotational measurement.