Ectopic ossification: This 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, 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. Osteomyositis refers to the abnormal ossification of the collagenous supporting tissues of tendons, ligamentous tendon membranes and skeletal muscles. There are two types, traumatic ossifying myositis and progressive ossifying myositis. The most common type is traumatic ossifying myositis. 1. Traumatic ossifying myositis: also known as limited ossifying myositis, only a single lesion is visible. It often occurs after trauma, but in a few cases it is complicated by other diseases, such as hemiplegia, gray matter in the anterior horn of the spinal cord, burns or tetanus patients. After trauma, intra-soft tissue hemorrhage may be the cause of ossification. Calcification and ossification in the soft tissues often appear 2-3 weeks after the trauma. Lesions are often found in areas susceptible to trauma, such as the elbow, femur, and hip. It is laminar in nature and may be associated with adjacent bones in one or more places. The lesion rarely extends to the ends of the bones and joints. Osteomyositis occurs in the anterior humerus muscle and is characterized by swelling and pain in the elbow joint area and limited passive and active movement of the elbow joint. After the pain and swelling have subsided, a hard, well-defined mass can be felt in the front of the elbow joint. The elbow joint is limited in extension and flexion due to muscle inelasticity, and flexion is significantly limited due to the blockage of the mass. x-ray features: limited swelling may appear soon after the injury. At 3-4 weeks after the injury, the swelling will show hairy dense images and the adjacent bone will show periosteal reaction. At 6-8 weeks post-injury, the margins of the lesion are clearly surrounded by dense bone and have the appearance of new bone. The core of the soft tissue mass is sometimes cystic and gradually enlarges its internal cavity to show an eggshell-like cyst in advanced stages. The mass shrinks 5-6 months after the injury, thus revealing an x-ray translucent zone between the mass and the adjacent bone cortex and periosteal reaction. 2. Progressive ossifying myositis: a congenital hereditary disorder, sometimes manifested as a familial disorder. It is more common in males and often develops in infants or children. The disease is often detected in the first few years of life. Early symptoms include pain, heat, and swelling in the affected area, followed by a hard mass in the subcutaneous tissue of the back, neck, and shoulders, with severe pain or pressure. At this time, fever may be combined. As the lesion becomes gelatinized, the mass in the subcutaneous tissue gradually shrinks to a hard and fixed mass. At this point, the symptoms of the acute phase disappear temporarily, and x-ray examination can already show that there are calcium salt deposits in the lesion. New lesions may then appear. As a result, a group of muscles, tendons and ligaments may be involved one after another. Minor trauma can aggravate the disease, so biopsies should be avoided. The disease stops progressing after about 30 years of age. The disease has a poor prognosis, mostly due to respiratory impairment or chronic starvation due to chewing and starvation ossification. The earlier the treatment of this disease, the better the results. Treatment of the disease with a combination of herbal medicine and physical factor therapy is highly effective and quick to recover, allowing the calcified muscles to be absorbed and their function restored for the purpose of rehabilitation. Ossifying myositis is a condition in which muscle tissue is mechanized 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 limitation 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 movements may prevent contractures. Progressive movement exercises should be used; inappropriate treatment can worsen ossification. Currently, the drug that is effective in preventing heterotopic ossification is Didronel (Etridronate disodium). This drug has the property of modulating the biological effects of ossification with pyrophosphates, which prevent soft tissue calcification in vivo. The acute phase after ossification is treated with EHDP (ethane hydroxyl-diphosphanate) (10 mg/(kg?d) to stop its progression. The effect on stable lesions is not significant, while it has a significant effect on inhibiting re-ossification at the surgical site. There are reports that internal administration of Chinese herbs that activate blood stasis, reduce swelling, and promote dampness and circulation can subside ossification and promote inflammation absorption and calcification. Excision of ossification that hinders activity must wait until 9-12 months or after the ossification is mature and the ossification is quiescent.