Split cord malformation - A study of 300 cases at AIIMS 1990-2006

Abstract

Background: Split cord malformation (SCM) is a rare condition. With decreasing incidence of neural tube defect (NTD) in the West, the reports of SCM are getting lesser and lesser. However, in India, spinal dysraphism is still a major problem encountered by the neurosurgeons.

Objective: Our aim was to analyze 300 patients of SCM for their clinical features, radiological findings and outcome of surgery, which can throw light on the subject to others, who have less scope of finding these cases frequently.

Materials and methods: Over a 16-year period, we encountered 300 cases of SCM at AIIMS. Over the same period, more than 1500 cases of NTD were managed. SCM was noticed in 20% of cases with NTD. Skin stigmata were noted in two-third of the cases, and scoliosis and foot deformity were observed in 50% and 48% cases, respectively. Motor and sensory deficits were observed in 80% and 70% cases, respectively. Commonest site affected was lumbar or dorsolumbar (55% and 23%, respectively). In 3% cases, it was cervical in location. Magnetic resonance imaging (MRI) scan revealed a large number of anomalies like lipoma, neuroenteric cyst, thick filum and dermoid or epidermoid cysts. All the patients were surgically treated. In type I, bony spurs were excised, and in type II, bands tethering the cord were released. Associated anomalies were managed in the same sitting. Patients were followed up from 3 months to 3 years.

Results: Overall improvement was noticed in 50% and stabilization in 44% cases and deterioration of neurological status was recorded in 6% cases. However, 50% of those who deteriorated improved to preop status prior to discharge, 7-10 days following surgery.

Conclusions: SCM is rare and not many large series are available. We operated 300 cases and noticed a large number of associated anomalies and also multilevel and multisite splits. Improvement or stabilization was noted in 94% and deterioration in 6% cases. We recommended prophylactic surgery for our asymptomatic patients.

Keywords: Good outcome; prophylactic surgery; role of magnetic resonance imaging; split cord malformation; surgery.

Figure 1

(a) 1½ year old child shows hypertrichosis. (b) Clinical photograph of a 6-year-old girl shows trophic ulcer right foot. (c) Clinical photograph of a 12-year-old boy with type I SCM and scoliosis. (d) Clinical photo of a 2-year-old girl with cervical SCM

Figure 2

(a) CT scan of a patient with SCM type I with posterior spur arising from lamina. (b) Axial MRI of spine showing type I SCM with two hemicords in two separate sheaths. One hemicord has syringomyelia. (c) Coronal MRI shows type I a spur at the center with large space above and below the spur

Figure 3

A case of caudal regression syndrome. (a) Sagittal MRI; (b) coronal MRI; (c) axial MRI slice shows type I spur

Figure 4

A 3-year-old male. (a) Coronal MRI; (b) coronal CT spine; (c) diagram shows SCM type IC