The global burden of ASD was huge compared with other self-reported chronic conditions in the general population of eight industrialized countries. The impact of ASD on HRQL warrants the same research and health policy attention as other important chronic diseases.

This study demonstrated that, if measures are to be used across cultures, the items must not only be translated well linguistically but also must be culturally adapted to maintain the content validity of the instrument at a conceptual level across different cultures. This may necessitate several validation studies to ensure and improve consistency in the content and face validity between source and target versions of a questionnaire due to difficulty in detecting subtle differences in the living habits of different cultures.

Short-segment transpedicular instrumentation of thoracolumbar burst fractures is associated with a high rate of failure that cannot be decreased by additional transpedicular intracorporeal grafting.

Pelvic fixation is still associated with a very high rate of mechanical failure. Major risk factors appear to be age and type of fixation. Although could not be shown to be statistically significant, failure to restore the optimal sagittal balance may be a contributing factor as well. So in conclusion, in cases with suboptimal sagittal plane correction, S2AI with polyaxial screws seem to have higher risk of short-term acute failure compared to IwL.

The results clearly indicate the potential of the intralaminar screw technique to provide stability that is equivalent to methods currently used. Given the serious complications that can follow vertebral artery injury and the decreased likelihood of injury by avoiding placement of C2 pedicle screw(s) and C1-C2 transarticular screw(s), strong consideration should be given to using a construct that incorporates C2 intralaminar screw(s).

Sagittal spinal alignment is found to be changing as a child grows. There is a statistically significant difference among different age groups, especially at cervicothoracic, thoracolumbar, and lumbosacral junctions. The position of the sacrum (inclination and translation), and spatial orientation, as well as the global magnitude of thoracic kyphosis, and lumbar lordosis changes with growth. These findings should be taken into consideration for the young patients who require spinal instrumentation. The question "whether sagittal alignment should be restored according to the normative data for the child's age or to the normative data for the adulthood" remains to be answered.

Based on our findings, posterior fixation with a pedicle screw-rod construct is suggested for 1-level PLIF and TLIF, and is necessary to achieve stability after interbody fusion across 2 levels using either technique.

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