Heterotopic ossification is the appearance of osteoblasts in the soft tissue and the formation of bone tissue. It mostly occurs around large joints, such as the hip and elbow joints. It is commonly seen in patients with neurological paralysis. The pathogenesis is not clear. The predisposing factors may be neurological and bioelectrical factors. In the early stage, there is significant localized swelling and pain, and joint movement is limited. In the late stage, joint movement is limited due to bone tissue formation. The basic pathological changes are active proliferation of primitive cells in fibrous connective tissue with abundant capillary network, calcium salt deposition, and bone formation. Mature heterotopic ossification has a bone structure with an outer layer of fibrous connective tissue, an inner layer of osteoblasts with trabecular nodes and osteoid tissue, and an active primitive cell center. It is thought that heterotopic ossification is somewhat different from ossifying myositis, which is the mechanization of muscle tissue due to injury or bleeding, resulting in the formation of hard knots and contractures. There is usually a clear history of local injury. Local pain is not always evident, but there is some degree of restriction of movement. Ossifying myositis may not be around the joint, but is more concentrated within the muscle. The etiology of heterotopic ossification is not well understood, making prevention difficult. Its development may be related to over-activity of the limb early in the injury. Once heterotopic ossification has occurred, early heat therapy, ultrasound, and massage of the affected area should be avoided in principle. Slow. Gentle exercise may prevent contractures. Progressive movement exercises should be used; inappropriate treatment can worsen ossification. Currently, the drugs effective in preventing heterotopic ossification are this drug has the properties of pyrophosphates that modulate the biological effects of ossification and prevent soft tissue calcification in vivo. It has been reported that internal administration of herbs that activate blood stasis, reduce swelling, and promote dampness and circulation can cause ossification to subside and promote inflammatory resorption and calcification. Excision of ossification that hinders activity must wait until 9-12 months or until the ossification is mature and the ossification is quiescent. Didronel is still available for about one year after surgery.