Diastematomyelia in children: treatment outcome and natural history of associated syringomyelia.

OBJECTIVE: To quantify the long-term outcome of children with diastematomyelia and the implication of syringomyelia in the natural history. MATERIALS: Retrospective study of 17 children (nine girls and eight boys) with diastematomyelia operated during 1989-2004. Mean age at diagnosis was 3.4 years (range 5 days-12 years), mean follow-up was 5 years; 14 had excision of spur and cord untethering, 3 had excision of spur alone.
RESULTS: The bony spur was in the lumbar region in 12 and thoracic in 5 patients. Syringomyelia was present in eight (47%), associated with bony spur between L1 and 4 (p=0.088), spina bifida occulta in ten (58.8%), and spinal lipoma in one (6%). Preoperative Necker Enfants Malades (NEM) scores were 17 in eight patients, 16 in four, 15 in three, 13 in one, and 12 in one patient. Presenting neurological deficits were motor in eight, sensory deficits in three, and anal incontinence in one patient. There was improvement of NEM scores postoperatively in five patients only, but still with residual deficit. Repeat spur excision and cord untethering was performed in three patients for neurological deterioration 1-4 years after first operation. On postoperative MRI scans syringomyelia remained unchanged in all eight patients. There were one skin infection, one transient motor deterioration, and one patient with sensory deficit after surgery.
CONCLUSION: Prophylactic operations were associated with the best clinical outcome. Despite improvement, all patients with established preoperative deficit still had residual neurological deficits at their last follow-up. The associated syringomyelia remained unchanged after surgery, indicating that it does not contribute to the neurological syndrome.