Treatment of spinal deformity with diastematomyelia type I: one-stage, two-stage surgery and new technique (vertebral column resection through wide bony septum)

Abstract

Study design: Case series, literature review, and technical note.

Objectives: To compare two different approaches to treat the spinal deformity with split cord malformation type I (SCM I). To present a new method of one-stage surgical treatment of congenital spinal deformity with wide bony septum (SCM I).

Methods: Analysis of the literature on the different types of combined surgical treatment of spinal deformities with SCM I was performed. We have provided our own data on 27 patients treated for congenital spinal deformity and SCM I, one of which underwent Schwab IV type osteotomy at the apex of the deformity through the bony septum and pedicles. Inclusion criteria were presence of spinal deformity in combination with SCM 1, performed surgery to correct spinal deformity, and follow-up period of at least 2 years.

Results: The result of the literature review was controversial and requires additional research. The average age of patients was 8.8 ± 6.6 years old. One-stage treatment of SCM I and spinal deformity was performed in 10 patients (group I) and two-stage in 14 patients (group II). Three patients with severe myelodysplasia, SCM I, and congenital kyphoscoliosis underwent correction of spinal deformity without SCM I removing (group III). The group I had the longest surgery duration (mean 289 ± 75 min) and largest blood loss (mean 560 ± 386 ml), a high percentage of deformity correction (mean 69.6%), and the highest rate of complications (60%). The most optimal was the two-stage treatment with the mean surgery duration 191 ± 137 min, mean blood loss 339 ± 436 ml, mean correction rate 63%, and frequency of complications 21%. The average follow-up time was 6.0 ± 2.6 years.

Conclusions: One stage surgery associated with a large surgical invasion and a large number of complications. It can be used in some cases, for example when the wide bony septum (SCM I) is localized at the apex of the congenital scoliosis or kyphosis. In all other cases, it is worth adhering to a two-stage treatment. Many new works demonstrate the relative safety and effectiveness of deformity correction without removing the SCM. In our opinion, indications for treatment of spinal deformity without SCM I removing can be the need to perform a shortening ostetomy outside the SCM zone. The remaining cases require a thorough assessment and a balanced decision.

Keywords: Congenital spinal deformity; Diastematomyelia; Split cord malformation I type; Vertebral column resection; Vertebral osteotomy.