Study Design Case report and literature review. Objective To describe a case of nontraumatic atlantoaxial rotatory subluxation (Grisel syndrome) and to review clinical and radiologic aspects, physiopathology, and treatment of this lesion. There is no well-established protocol in the management of patients without spontaneous reduction. The authors discuss the available strategies to achieve reduction and when to operate on these patients. Methods Case presentation of a 7-year-old patient who presented with torticollis ∼1 week after the onset of an upper airway infection. There was no history of head or neck trauma. Computed tomography demonstrated atlantoaxial rotatory subluxation and a normal atlantodental interval. Results The patient was treated with nonsteroidal anti-inflammatory drugs and antibiotics and by progressively increasing the soft cervical collar height. Clinical reduction of the subluxation occurred after 48 hours. He wore the rigid collar for 6 weeks. At that moment, the patient was completely asymptomatic and follow-up cervical spine radiograph demonstrated an anatomical C1-C2 relation. The patient was instructed to return to daily life activities in a gradual manner. Conclusions Grisel syndrome should be considered in the differential diagnosis of torticollis, especially in children. The management can be planned according to the classification of Fielding and Hawkins. The initial treatment involves medicines, injury reduction, and cervical spine immobilization. Surgical treatment is indicated only in cases of failure of conservative treatment, recurrences of subluxation, and irreducible subluxations.