Buckling collapse of the spine in childhood spinal tuberculosis.

We prospectively followed 61 children under 15 years of age at the time of diagnosis to identify the risk factors for deformity progression. The children had 63 lesions and a minimum of 15 years followup. All exhibited an increase in deformity during the active disease phase, but 26 of 63 (41%) continued to progress during the quiescent phase until the growth was complete. In 21 of those 26, there was an increase in angular kyphosis with a final deformity < 90 degrees. In the other five, the deformity resembled a buckling collapse analogous to failure of an axially loaded slender column; the deformity was more than 100 degrees and associated with facet dislocation at multiple levels. These patients' vertebral segments above the level of destruction underwent severe sagittal rotation resulting in horizontal vertebrae with vertical growth plates, which resulted in longitudinal overgrowth of the vertebral segments. Risk factors for buckling collapse included an age of less than 7 years at the time of the disease, thoracolumbar involvement, loss of more than two vertebral bodies, and presence of radiographic spine-at-risk signs. Children at risk for buckling collapse must be carefully watched and the spine stabilized to avoid a massive increase in deformity.