The normal appearance of the spine is straight from behind. After a person suffers from lumbar disc herniation, the body often unconsciously adopts a series of self-protective positions in order to reduce the stimulation of the herniated nerve roots and relieve pain. The direction of scoliosis of the spine can be either convex to the healthy side or to the affected side, depending on the corresponding position of the herniated object in relation to the compressed nerve root. If the herniated disc is on the lateral side of the nerve root (suprascapular), the patient’s spine bends to the healthy side, the herniation reduces the irritation of the nerve, and the pain is significantly reduced. If the herniated disc is on the medial side of the nerve root (axillary type), when the patient bends to the healthy side, the irritation to the nerve root is increased and the pain is relieved; if the herniated disc tops the nerve root or there is adhesion between the two, there is pain whether the patient bends to the affected side or to the healthy side. It is worth noting that the above rule is more typical in patients with lumbar 4/5 disc herniation, while in patients with lumbar 5/sacral 1 disc herniation, scoliosis is not obvious, mainly because the lumbar 4 vertebrae are more flexible than the lumbar 5 vertebrae in terms of lateral movement.