[Evaluation and treatment of congenital scoliosis with split cord malformation]

To discuss the diagnosis and surgical treatment of congenital scoliosis (CS) with split cord malformation (SCM).

From May 1999 to June 2004, 353 cases of CS were admitted, and 58 cases were diagnosed CS combined with SCM via myelography and (or) CTM. According to Pang's classification for SCM, patients were divided into type I SCM and type II SCM. Two cases gave up operation, and surgeries were performed in 56 patients. Except that one case with arachnoid cyst underwent intraspinal exploration, all other 55 cases underwent spinal correction without dealing with the intraspinal abnormalities. Clinical manifestation, radiological findings, operative methods and results were retrospectively analyzed in this paper.

There were 11 patients (19%) with type I SCM and 47 patients (81%) with type II SCM. In the 56 cases who had surgical treatment, the Cobb angle in the patients with type I SCM (11 cases) was (60 +/- 25) degrees, and in type II SCM (45 cases) was (67 +/- 21) degrees pre-operation. The Cobb angle in type I SCM was (29 +/- 13) degrees and in type II SCM was (39 +/- 19) degrees post-operation, with the correction rate (51 +/- 17)% and (41 +/- 24)% respectively. No statistic differences were found between both types. And there were no new neurological deficits in both groups after the spinal correction operation. After average 17.3 months (4-59 months) follow-up, the correction loss was (6 +/- 10) degrees, (5 +/- 8) degrees in 7 patients with type I SCM and (6 +/- 10) degrees in 19 patients with type II SCM. There was no statistic difference in correction loss between both types. In the follow-up, the neurological symptoms and signs of the patients were stable.

Considering the incidence of intraspinal anomalies in patients with congenital scoliosis, intraspinal examination via myelography, CTM or MRI should be performed prior to spinal correction surgery. For congenital scoliosis with type I SCM, the bone spur need not be excised before spinal correction if there is no signs of spinal cord tethered and the bone spur locate in the middle of the split cord where there are much space to accommodate it. For congenital scoliosis with type II SCM, if there are no progressive neurological manifestations, the split cord in the single tubular can tolerate the manipulation of spinal correction as the normal spinal cord.