Spinal dysraphism is a broad spectrum of congenital anomalies affecting the spine and cord. Lipomyelocele occurs most commonly in the lower lumbar and sacral region as in this case. There is usually a large posterior sacral defect, prominent subcutaneous fatty lesion that extends into the spinal canal, prominent anterior subarachnoid space and extrusion of some of the neural element posteriorly through the defect.
Lipomyelocele is one of the closed forms of spinal dysraphism, which means that the defect is always covered with skin. Low-lying tethered spinal cord is a very common association. It is also important to look for other congenital anomalies such as diastematomyelia, syrinx or other anomalies of the brain.