It is common to see children with no obvious reason for head tilt and limited neck movement, which is often overlooked by parents, but in fact many of these children are suffering from subluxation or dislocation of the circumflex spine. The clinical characteristics: ① No obvious cause or minor head trauma, neck infection. ②A characteristic head and neck deviation is observed. ③The circumferential subluxation, dislocation or rotational displacement of the circumferential spine can be detected by X-ray examination and CT. Pay attention to differentiate it from diseases such as myelomeningocele, congenital cervical hemivertebrae, and acute tonsillitis. According to Fielding X-ray, there are four types: Type 1: rotational displacement of the crico-axial joint (fixed) with radiographic annular tooth distance (ADI) less than 3 mm; Type II: rotational displacement of the crico-axial spine (fixed) with ADI 3-5 mm; Type III: rotational displacement of the crico-axial spine (fixed) with ADI greater than 5 mm; Type IV: rotational displacement of the crico-axial joint (fixed) with posterior dislocation of the crico-axial spine; ④ Age of prevalence: 3 -6 years old (75%), with type 1 and 2 predominating. Causes: 1. Local or neighboring site infection causes joint ligament laxity. 2. Injury to the joint ligaments due to trauma. 3. Inflammation or entrapment of the synovial folds of the joint. 4. Asymmetric development of the circumflex joint. 5.Other unknown causes. Treatment of this disease: Once diagnosed, the earlier the treatment, the better, by bed pillow chin traction, swelling and other symptomatic treatment 1-2 weeks, more can be cured. Very few conservative ineffective, need surgery. If misdiagnosed and mistreated, long-term annular pivot joint dislocation or subluxation can lead to annular vertebral joint rotation (fixation) and secondary compensatory annular occipital joint rotational dislocation, resulting in instability of the occipital annular pivot complex and even fatal spinal cord compression with serious consequences. Long-term rotational deformity of the crico-occipital joint can also produce facial asymmetry, strabismus and vertigo, which can cause irreversible damage to the child. Therefore, sudden “tilted head” in children should be highly valued by parents and clinicians to avoid missing the best time for treatment.