Surgical treatment of split cord malformation

Objective To study the surgical treatment of split cord malformation （SCM）. Methods Twenty-one cases of SCM （9 males and 12 females） admitted to our department in January 2005-January 2009 were retrospectively analyzed. Twelve cases were diagnosed with type I SCM and 9 with type II SCM, respectively, following Pang classification. Longitutinal fissure was located in thoracic, thoracolumbar, lumbar, and lumbosacral segments of 6, 6, 7, and 2 cases, respectively. Excision of bony crest and filum terminale, reshaping of dura mater cyst were performed in 12 cases of type I SCM, while release of fiber bundles and excision of filum terminale were performed in 1 and 4 cases of type II SCM, respectively. Results Of the 17 cases undergone surgery, 15 were followed up for 3-48 months （averaged 15 months）. Significant, partial, and no improvement in symptoms was found in 5, 6, and 4 cases, respectively, with no exacerbation of symptoms observed in any case. Conclusion Early surgery should be considered for all cases of type I SCM, even for the asymptomatic cases. The indication for type II SCM patients is progressive neurological dysfunction, and release of fiber bundles or excision of filum terminale should be selected according to the different causes for tethered spinal cord.