Contracture of the sternocleidomastoid muscle on one side can cause a squint, the incidence of which is 0.3~0.5%. Congenital sternocleidomastoid can appear after 10~14 days after birth, first a mass in the muscle, and then gradually fibrosis and contracture. Etiology: 1. Intrauterine developmental disorders. The fetal position is not correct, the head is in posterior extension or anterior flexion position, the fetal head is pressed or the amniotic fluid is too small causing adhesions on one side, or the fetal development is impaired. 2. Birth injury. The sternocleidomastoid muscle is torn, forming hematoma, adhesions, or fibrosis to form scar, in 50-70% of patients with history of breech delivery, obstructed labor, and forceps assisted delivery. Pathological observation shows that the muscle fibers are completely replaced by fibrous tissue. 3. Blockage of blood supply. Extreme distortion and compression of the neck (including intrauterine and during delivery) causes ischemia of the muscles …… In addition, there is a spastic squint, due to reflex stimulation, in which three groups of muscles are involved: (1) the short muscles between the atlantoaxial vertebrae and the skull; (2) the large muscles of the neck, including the sternocleidomastoid, rhomboid, and oblique angle muscles; (3) the hyoid muscles. It may be caused by functional disorders of nerve cells or basal ganglion lesions. Clinical manifestations: 1. The head and neck tend to be on the affected side, the head is tilted and rotated to the opposite side, the cervical vertebrae are convex to the healthy side, and the ear and shoulder distance on the affected side are close. 2. The sternocleidomastoid muscle on the affected side is tense, contracted, and hard, and the sternal head is clearly convex. The mass protrudes significantly when the head is turned to the healthy side. The size of the face is asymmetrical. Treatment methods: 1.Manipulation treatment. Location: sternocleidomastoid muscle, rhomboid muscle, muscle belly of the oblique angle muscle, muscle starting and ending points. Specific operations: kneading, pressing, pointing, plucking, lifting, tendon management, pulling the head and neck to pull the sternocleidomastoid muscle. 2, family members with. Including massage, posture correction (sleep, nursing so that the head turned to the healthy side), etc. 3.Surgical treatment. Sternocleidomastoid muscle release, severance or excision. Pay attention to protect the deep paramedian nerve, common carotid artery, internal jugular vein, etc. Prognosis: The efficacy and prognosis of the disease are related to the severity of the disease, the age of treatment, whether the treatment is correct, and whether the treatment can be adhered to, etc. The efficacy of the disease is obvious in milder cases and younger ones. Therefore, once diagnosed, it should be treated as early as possible.