Joint dislocation is also known as joint dislocation. When trauma acts on the joints, the articular surfaces of the bones of the joints lose their normal relationship, i.e., the bones of the joints leave their normal position under the action of external forces, so that the joints lose their functions, which is called joint dislocation. The causes of joint dislocation are: 1, traumatic dislocation Due to trauma, violence and other reasons for joint dislocation, joint dislocation in joint dislocation accounted for the vast majority, but also the main cause of joint dislocation. These traumas and violence include car accidents, crush injuries, fall injuries and so on. 2.Congenital dislocation is mainly caused by congenital developmental abnormality of bones, and the most common one is hip dislocation caused by congenital hip dysplasia in children. Congenital dislocation is mostly seen in adolescent patients. Pathological dislocation is mainly caused by diseases that damage the joints or the bones that make up the joints, resulting in dislocation of the joints. Common causes of pathological dislocation include tumor, tuberculosis, rheumatoid arthritis and other causes of joint destruction, resulting in dislocation. 4.Habitual dislocation The cause of habitual dislocation is often the first time the joint dislocation is not timely treatment or reset without proper fixation, resulting in joint capsule or ligament laxity. When the joint is again subjected to slight external force, it will cause joint dislocation. Habitual dislocations of the shoulder and jaw joints are common. Joint dislocations are generally categorized into two types: complete and incomplete dislocations. Complete dislocation refers to the complete loss of normal alignment of adjacent joint surfaces. Incomplete dislocation, also known as subluxation, is a partial loss of alignment of the adjacent joint surfaces after dislocation. These two types of dislocations can be differentiated by taking x-rays and observing the changes in the shape of the joint. If the dislocation occurs within 2 weeks, it is called a fresh dislocation. Most trauma-induced dislocations are fresh dislocations. If the joint is dislocated for more than 2 weeks, it is called an old dislocation.