Clinically, patients with bone or muscle lesions can be immobilized in a plaster cast, which is used differently for different parts of the disease. Patients with complete rupture of the Achilles tendon are treated surgically and can be immobilized with a unilateral plaster cast after surgery. Tibiofibular fracture is treated by manipulation, and can be immobilized with upper and lower plaster casts. If a child or infant has a congenital dislocation of the hip, a hip herringbone cast can be used for immobilization. If the patient has an ankle fracture combined with a talus dislocation, the ankle can be fixed in an ankle inversion position with a U-shaped plaster cast after manipulative reduction. Therefore, different parts of the body are immobilized with different methods of plaster fixation, and the specific method of fixation should be fixed under the guidance of the doctor.