DIASTEMATOMYELIA (CONGENITAL CLEFTS OF THE SPINAL CORD)

Abstract

Diastematomyelia associated with the presence of a bony spicule arising from the posterior aspect of a vertebral body and transfixing the spinal cord or cauda equina has been encountered in 11 operative cases. In the last nine of these the diagnosis was made previous to operation. It seems apparent that progressive neurologic impairment of the lower extremities and of the rectal and vesical sphincters may result from increasing distortion of the neural axis as a result of fixation produced by these bony spicules during the growth period. The diagnosis is suspected in the presence of cutaneous midline defects, muscular imbalance in the lower extremities, gait disturbances, deformities of the feet, urinary or fecal incontinence or increasing enuresis. The diagnosis is confirmed on roentgen examination by the presence of a midline opacity usually in the region of a spina bifida or other vertebral anomaly or by visualization of two separate subarachnoid channels on myelography. Operative treatment consists in laminectomy with extradural removal of the bony spicule insofar as possible, followed by opening the dura with excision of its reflections adjacent to the spicule, excision of the remaining bony prominence down to the anterior dura, and division of all adhesions to the bifid cord or cauda equina until the latter is freely movable within a single dural canal. In all these cases there appeared to be complete division of the cord or cauda equina into separate parts rather than reduplication of the cord. Each half of the neural axis was invested with its own meninges. The operative findings in the 11 cases reported here, together with the brief follow-up observations noted to date, have convinced the authors that it constitutes good preventive medicine to carry out surgical treatment of diastematomyelia associated with spina bifida occulta at any time the diagnosis is made during infancy and early childhood.