Once a contusion or a violent blow has been received, the local soft tissues become scarred, and the elasticity of the scar tissue is obviously different from that of the normal muscle tissue, once the trauma is more serious and the scope of the scar tissue is larger, there will be a sunken pit on the thigh, which usually has no There is no pain or discomfort, but there may be a slight soreness and swelling or local tension. If there is no previous trauma, it is necessary to consider whether the muscles are dystrophic, if patients with lumbar disc herniation, lumbar disc bulge or even spinal stenosis, long-term stimulation of the sciatic nerve may lead to local muscle dystrophy, resulting in the phenomenon of a depression on the top of the leg.