[Grisel's syndrome : about two cases of a atlantoaxial (C1-C2) subluxation].

Grisel's syndrome is a non-traumatic atlantoaxial (C1-C2) subluxation and one of the causes of torticollis in children. The subluxation occurs in the context of an infection in the ENT ("Ear Nose and Throat") region or following surgery. Diagnosis is based on clinical examination and radiological assessment. Treatment is typically medical and conservative, with surgical interventions reserved for recurrences and late presentations. We discuss here two cases of C1-C2 subluxation. The first case involves a 10-year-old child with subluxation following a rhinopharyngitis. This presentation is the classical manifestation of Grisel's syndrome. Prompt management led to correction of the subluxation using medical treatment and a soft Philadelphia collar. The second case involves a 34-year-old adult who developed posterior headaches after sphenoidotomy surgery. Grisel's syndrome is less common in adults, leading to clinical challenges and delayed diagnosis (> 1 month). Reduction combined with a halo vest treatment failed, and the patient required cervical arthrodesis.