”Spinal cord tethering syndrome” is a general term for a series of symptoms that result when the spinal cord is torn and cannot grow and move properly. So what is the spinal cord supposed to look like? Why is it tethered? The spinal cord is part of the body’s central nervous system and is located in the spinal canal consisting of the cervical, thoracic, lumbar, and sacral vertebrae. The upper end of the spinal cord connects to the medulla oblongata in the brain, and pairs of nerves, called spinal nerves, emanate from the sides, which then continue to the limbs, skin, and internal organs. The lower end of the spinal cord has an enlarged area called the lumbosacral dilation, from which the spinal cord begins to thin and tail off, forming a cone at the end, called the spinal cone. The outer membrane that envelops the spinal cord, the spinal cord membrane, continues below the spinal cone to form a long bundle of terminal filaments, located below the second sacrum and wrapped by the dura mater, which extends to the back of the coccyx. There is no nerve tissue inside the terminal filaments, which provide some anchoring of the spinal cord. The spinal nerves that emanate from the lumbosacral region are essentially vertical downward, forming a cauda equina-like structure around the terminal filaments. （If the cauda equina is damaged, abnormal sensation and burning pain in the perineum and lower extremities will occur, and in severe cases, urinary and fecal disorders may occur. However, not everyone’s spinal cord grows as soon as they are born. The spinal cord grows slowly as the baby is formed in the mother’s womb and grows until birth and adulthood. Normally, when a mother is first pregnant and the baby is forming a human form, the baby’s spinal cord is the same length as the spine. But slowly, the spinal column grows faster than the spinal cord, and the top of the spinal cord is fixed at the bottom of the brain (Figure 3), so the end of the spinal cord is gradually moving upward in the spinal canal. When the baby grows to 20 weeks in the mother’s womb, the spinal cord cone at the end of the spinal cord moves upward between the baby’s 3rd and 4th lumbar vertebrae; at 40 weeks it moves to the position of the 3rd lumbar vertebrae, and at birth it has moved upward between the 1st and 2nd vertebrae. Three months after birth, the spinal cord cone rises to the position of the 1st lumbar vertebra and becomes the same as that of an adult. At this time, the spinal cord cones become thinner and move downward to become the terminal filaments (less than 2 mm in diameter in adults). (Figure 4) The terminal filaments of the spinal cord, cauda equina roots, etc. are attached to the inner wall at the end of the spinal canal, like a bull’s nose tied to a stake with a rope. Under normal conditions, the rope is long and the cow can move around the stake for a certain distance and can graze freely. If the rope is very short, or no rope at all, the cow’s nose is pulled, or even directly tied to the stake, severely limiting the range of activities. This is called “tethering”. If the terminal filament or cauda equina is torn during the growth and rise of the spinal cord, the spinal cord cannot work properly, and this is called spinal cord embolism. This causes degeneration, edema, and necrosis of the spinal cord, resulting in a series of symptoms called “spinal cord embolism syndrome. What are the causes of spinal cord tethering? Depending on the cause, spinal cord tethering syndrome (TCS) can be divided into primary TCS and secondary TCS, which occurs when the spinal cord is tethered to the spinal canal due to incomplete closure of the neural tube, lipoma, spinal cord cone cyst or teratoma, or longitudinal fracture of the spinal cord, and the spinal cord is stretched and the cone cannot rise normally, causing the cauda equina and the terminal filaments at the end of the spinal cord to be Although this spinal cord tethering is formed during the development of the individual, it is not considered to be a genetic disease in the general sense. The vast majority of children and most adult patients presenting to the hospital with primary TCS have spinal cord adhesions due to spina bifida repair surgery in the lumbosacral region, or after intradural surgery in the spinal canal, and the scar tissue at the surgical site adheres to the spinal cord and cauda equina, causing the lower end of the spinal cord to be stretched as the scar contracts. .