1. When is congenital spina bifida formed? What is the cause? Congenital spina bifida forms early in the mother’s pregnancy, around 40 days of gestation, due to a variety of factors that cause defects in neuraxial and mesodermal development, resulting in incomplete closure of the neural tube and spinal canal. No single causative factor has been identified; the more definitive factor is folic acid deficiency. In my clinical work, I found that the vast majority of children with neural tube anomalies come from rural areas and areas with relatively poor living conditions and nutritional status. Therefore, I personally believe that the improvement of public health environment and the overall nutritional status of the whole population is the key to reduce the occurrence of neural tube abnormalities. 2. What are the categories of congenital spina bifida? Congenital spina bifida is divided into two categories: manifest spina bifida and recessive spina bifida: manifest spina bifida is a condition in which the contents of the spinal canal (e.g., spinal membrane, spinal cord, spinal nerve) bulge out of the spinal canal through a defect in the vertebral plate, resulting in a cystic mass on the back of the child (usually in the midline area of the back). Pathology is broadly divided into the following categories: 1. Spinal membrane bulge: can occur in any segment of the spine. The spinal membrane bulges outward from the vertebral plate defect, and the capsule contains cerebrospinal fluid, not spinal cord or nerve tissue. 2, spinal cord spinal membrane bulge: mostly occurs in the lumbosacral segment of the spine, refers to the spinal membrane through the vertebral plate defect to the dorsal expansion of the capsule, the capsule spinal cord, cauda equina, as well as soft spinal membrane, arachnoid membrane, usually also contains deformed neural tissue. 3, lipoma type spinal cord spinal membrane bulge: mostly occurs in the lumbosacral segment of the spine, refers to the spinal cord spinal membrane bulge at the same time, the subcutaneous fat abnormal growth, through the vertebral plate fissure and bulging bursa wall or bulge close adhesion. The spinal cord is stretched. 4.Lipoma inside and outside the spinal canal: mostly occurs in the lumbosacral segment of the spinal column. It refers to the abnormal growth of subcutaneous fat, which enters the dural sac through the vertebral plate fissure and adheres closely to the dorsal side of the spinal cord and grows with the mixed nerve tissue, with unclear boundaries in the spinal cord, forming compression and tension on the spinal cord. As the name implies, occult spina bifida may have no or only mild manifestations on the surface, such as the presence of sinus openings, local hyperpigmentation, abnormal hair growth, local skin thinning or scarring, and local skin capillary hemangiomas. The pathology is divided into the following categories: 1. Subcutaneous sinus tracts: can appear in any segment of the cranial-spinal dorsum. The sinus tract enters the vertebral canal cavity via the lamina fissure. A small portion terminates on the surface of the dural sac, and most enter the dural sac and travel along the surface of the spinal cord. It is often combined with a dermatomal cyst or an epidermoid cyst. 2. Dermatomal cyst or epidermoid cyst: it can exist alone or be connected with subcutaneous sinus tract. The wall of the cyst is squamous epithelium containing many sebaceous glands and hair follicles with a secretory function, resulting in the accumulation of wax-like material in the cyst, which is the secretion or decomposition product of sweat glands, sebaceous glands and hair follicles. The cyst may be embedded in the spinal cord or located on the surface of the spinal cord, or in the cauda equina nerve, causing compression of the spinal cord and cauda equina nerve. It can also be combined with infection and cause septic meningitis; 3. Longitudinal spinal cord fracture (bony crest type): that is, the spinal cord is divided into two and covered by the respective dura and arachnoid membranes, while the two are separated by fibers, cartilage or bony crests, and the spinal cord is thus stretched. This produces clinical symptoms. It also includes other spinal cord lipomas and spinal cord cavities. Congenital spina bifida may be combined with other central nervous system malformations such as Chiari’s malformation and spinal cord hypoplasia, as well as spinal deformities such as scoliosis, hemivertebrae, and vertebral fusion.