A herniated disc can be retracted after proper treatment. When a disc is herniated, it is inevitably accompanied by a rupture of the annulus fibrosus and a backward extrusion force that causes the disc to protrude backward. Similarly, when treating a herniated disc, traction is used to create a state of negative pressure in the intervertebral space, which causes the herniated disc to retract and retract due to suction. In addition, the posterior longitudinal ligament acts as an auxiliary retraction and retraction while traction is applied. When traction is applied, the posterior longitudinal ligament is very tightly tensed, and when it is tensed, the herniated disc is subjected to forward pressure, which then causes the disc to retract and retract.