[The lumbar spine in profile after Harrington's operation. Apropos of 100 cases].

After Harrington's procedure, the authors analyse anatomical modifications observed on the 3 last grafted vertebrae and on the underlying healthy lumbar segment. At the level of the grafted vertebrae it was observed a quite constant discal piching and a change in morphological aspect of the vertebra which become higher than large. The ratio between width and length physiologically at 1,20 was at 0,96. At the level of mobile underlying segment to the graft, lordosis remains at physiological value, although distributed on a shorter lumbar segment and that without change in discal angle. This fact was induced by an increase of the lordosis percentage incumbent to the vertebral body. This percentage physiologically at 10 passed 30 after Harrington's procedure because of an increased wedge-shaped of the 4th and 5th lumbar vertebra. This phenomenon was as much marked as the graft was precociously performed and as they descended lower. This might explain the good long term tolerance for the increased work of the free underlying rachis to a Harrington's procedure.