Revue de chirurgie orthopédique et réparatrice de l'appareil moteur vol:81 issue:5 pages:428-32
PURPOSE OF THE STUDY: CD instrumentation has been presented as a system which is able to achieve a 3-dimensional correction of idiopathic scoliose. We performed a prospective study about the apex derotation following CD instrumentation. MATERIALS AND METHODS: 24 consecutive patients with idiopathic scoliosis were included in this study. On pre- and postoperative CT scans the rotation angle relative to the sagittal plane according to Aaro and Dahiborn (RA sag) were measured the pre- and postoperative 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 instrumented levels and with the different King types of scoliosis. RESULTS: There was no statistical significant increase or decrease of the rotation if we consider the sag without taking into account the type of curve. DISCUSSION: The different ways to measure rotation in scoliosis are presented. The limits of the method we used (RA sag) are also discussed. We reviewed the literature concerning derotation with CD instrumentation to compare it with our results. CONCLUSION: The evaluation of rotation in scoliosis is not easy. The CT scan seems to be the best method. Nevertheless, the postoperative changes of the morphology of the patient can be a factor of error in rotational measurement.