V. Relationship with lower extremity force lines Some researchers have suggested that growing pain is caused by improper force lines in the lower extremity due to poor posture. evans AM et al. found that many children presenting with complaints of lower extremity pain had a foot rotation front, and that this poor posture could be corrected with insoles or orthotics to reduce the occurrence of pain. It is suggested that growing pain may be closely related to poor posture of the foot, or unstable gait during rapid development, uneven force on the joint surface, and incorrect line of force for weight-bearing leading to instability of the knee joint and causing pain. Sixth, the relationship with pain Min value Some people believe that the reason why children with growing pain have pain is because the pain threshold is reduced. The sensitivity of pain perception is higher, which leads to pain more easily than normal children under the same conditions. The reason why the lower extremity pain discussed in this paper is called “growing pains”. The main reason is that it always occurs during childhood development, when bones are growing rapidly. At night, when the bones grow rapidly, the surrounding nerve muscles are strained, causing pain, and since the day the bones grow slowly, the pain is relieved. The relationship with mental factors Foreign research found that children with growing pains are accompanied by recurrent abdominal pain, negative emotions, inattention and behavioral problems in addition to lower limb pain, and can often be characterized as aggressive, agitated and active. This suggests that psychosocial factors are a contributing factor to the development of growing pains. In conclusion, the occurrence of growing pain may be related to calcium and phosphorus metabolism, bone density, bone age development, lower limb microcirculation, limb overuse, lower limb force line misalignment, reduced pain threshold, skeletal growth, and psychological factors. The exact mechanism of its occurrence needs to be further investigated.