The true pathogenesis of crista longitudinalis is still unclear. At present, most scholars agree with the “unified theory” proposed by Pang et al. in 1992, which suggests that crista medullaris is caused by abnormal development during the closure of the embryonic neural tube, i.e., during the closure of the neural tube, a paraneural tube surrounded by the mesoderm forms between the yolk sac and the amniotic membrane, and an endodermal canal is formed to crack open the crista and neural plate, resulting in the appearance of two neural tubes. The Pang subtype is similar to other subtypes. Pang staging has the advantage of being less confusing on imaging than other staging methods and is a better guide for surgical planning. There are two main types: Type I, in which the two halves of the crura have their own separate dural canal with a bony or cartilaginous septum; and Type II, in which both halves are located within a common dural crura with a fibrous septum. The symptoms are classified as asymptomatic, mild, moderate and severe with reference to Hoffman et al. Mild degree: basically smooth urination with occasional dribbling, occasional dry stool, no foot deformity, no decrease in muscle strength of lower limbs. Moderate: poor urination, dribbling, dry stool, foot deformity, no or mild lower limb muscle atrophy, able to walk. Severe: poor urination, incomplete dripping, and urinary retention. Dry stools and difficulty in defecation. Significant inversion deformity of the foot, significant muscle atrophy of the lower limbs, difficulty in walking. The bony partition is seen intraoperatively and is completely removed intraoperatively. As the body grows taller, the crestal medulla, especially the crestal end, is constantly stretched and cut, causing damage to the crestal medulla, while the blood vessels supplying the crestal medulla become thin and blood flow is impaired, further aggravating the damage to the crestal medulla. With the growth of age and the unequal development of the crestal medulla and the crestal column, the strain on the crestal medulla at intervals will increase, and the dysfunction will become more serious. In addition, children with deformed bone tissue are small and have mostly cartilage components, so the surgery is easy to operate. The principles of surgery are as follows: ① microscopic operation; ② use high-speed grinding drill and nerve stripper to protect the cremaster; ③ prohibit excessive pulling and vibration of the cremaster; ④ remove the bony separation as much as possible, but if the bony separation is wide, only the caudal separation can be removed when total excision is difficult, and it is enough to release the division of the cremaster by the separation. ⑤ Protect the vessels supplying the crestal pulp.