The embryological failure of the neural tube to fuse or close completely thereby resulting in the vertebrae overlying the open portion of the spinal cord not to fuse and remain open leaving the spinal cord exposed
Rachischisis is a developemental birth defect. The posterior neuropore of the neural tube of the developing embryo in the uterus failed to close completely. Rachischisis may affect anywhere along the vertebral axis; it may also affect the entire spine.1
Rachischisis is found to occur commonly with cranial neural tube defects such as anencephaly, acrania, iniencephaly, and myelomeningocele.
Rachischisis is a form of spina bifida, which is a defect during embryological development characterized by an incomplete closing of the backbone and membranes surrounding the spinal cord. Two major types of spina bifida include the spina bifida occulta and the spina bifida cystica. Rachischisis is a subtype of spina bifida cystica together with the other subtypes such as meningocele and myelomeningocele. Rachischisis is described to be the most severe form among the three subtypes.2
Word origin: Greek rachis (spine) + schizein (to split)
- spinal dysraphism
- cleft spine
1 Özek, M., Cinalli, G. & Maixner, W. (2008). Spina bifida management and outcome. Milan New York: Springer.
2 Kavanagh, S. and Tidy, C. (2014). Spina Bifida. Retrieved from http://www.patient.co.uk/doctor/spina-bifida-pro