Spinal Dysraphisms: A New Anatomical–Clinicoradiological Classification

Background Spinal dysraphisms refer to the congenital abnormalities of the spine and spinal cord due to aberrations in the processes of gastrulation, primary neurulation, and secondary neurulation. Embryology of many complex spinal dysraphisms are yet poorly understood and there is no agreeable anatomical–clinicoradiological classification with inclusion of recently documented and complex spinal dysraphisms. Aims and Objectives The main objective of this study was to review the imaging features of spinal dysraphisms with a better understanding of embryological abnormalities and propose a new classification inclusive of all complex and unusual dysraphisms based on anatomical and clinicoradiological correlation. Materials and Methods This was a retrospective single institutional observational study of 391 cases of spinal dysraphism for 10 years in our institution. Of 391 cases included in the study, 204 were males and 187 were females. Also, 123 cases belonged to the 0–6 months age group, 38 cases belonged to the 7–12 months age group, 156 belonged to the 1–5 years age group, 39 cases belonged to the 6–10 years age group, and 35 cases belonged to 10–20 years age group. Results An anatomical–clinicoradiological analysis of cases yielded a high proportion of cases of spinal lipomas, including lipomyeloceles and lipomyelomeningoceles (31.3%) and posterior myelomeningocele (14.2%). Anterior myelocoele (0.2%), sacral chordoma(0.2%), and intrasacral meningocele (0.2%) formed the least proportion of cases. A new classification was proposed based on the analysis of acquired data. Conclusion A structured approach in imaging spinal dysraphism is necessary for imaging evaluation in recent years. The proposed new classification based on clinicoradiological correlation and anatomic location is inclusive of unusual and complex dysraphisms.

Treatment of a sacral fracture associated with an intrasacral meningocele: A case report

We report a case of sacral fracture complicated by an intrasacral meningocele in a 37-year-old male. The patient had a left sacral fracture with bilateral fractures of the superior and inferior pubic rami. The sacrum was fixed with a posterior plate and both superior pubic rami were fixed with an intramedullary screw. However, computed tomography myelogram and magnetic resonance imaging showed the intrasacral meningocele with the leakage of the cerebrospinal fluid into the buttocks and developed delayed union. Reoperation utilizing a strong anterior and posterior internal fixation combined with posterior bone grafting was undertaken and bone union was obtained.

Intrasacral meningocele in the pediatric population

Object Intrasacral meningoceles are rare cystic lesions that can cause focal compression within the bony sacral canal. Their mechanisms are poorly understood, but most intrasacral meningoceles appear to be intrasacral extradural cysts caused by arachnoid herniating through a small dural defect in the caudal end of the thecal sac. As opposed to perineural cysts, they are not associated with an exiting nerve root. When symptomatic, they can cause sacral pain or sacral nerve root dysfunction due to local compression. Methods This is a retrospective series from Boston Children's Hospital. All patients in whom symptomatic intrasacral meningocele that required surgical treatment was diagnosed between May 1994 and March 2011 were included in the study. Spine MRI was the diagnostic modality of choice. All patients underwent sacral exploration, with ligation and obliteration of the cyst. Resected cyst wall was subjected to pathological examination. Results There were 13 patients (11 boys and 2 girls) who underwent operation for intrasacral meningocele. The median age was 8 years (range 5 months–16 years). The most common presenting symptom was back pain (in 5) often described as deep tail bone pain, followed by urinary incontinence (3) and constipation (2). Three patients had evidence of associated tethered cord on MRI studies. Four patients were asymptomatic and their diagnosis was made following imaging for other reasons; they were surgically treated because of the increasing size of the lesion or association with other congenital lesions. Most patients had symptomatic improvement after surgery. Conclusions Intrasacral meningoceles are rare lesions that may result from a congenital dural weakness and a resultant arachnoid diverticulum. They present in childhood either incidentally or with symptoms secondary to nerve root compression. Identification of the point of herniation through the dura mater and ligation of the lesion provides cyst cure and resolution of symptoms in most patients.