Background: Atlanto-Axial Rotatory Subluxation is an acquired condition, usually occurring in pediatric patients, because of either trauma or pharyngitis or ear-nose-throat ( ENT) surgery or upper respiratory tract infection. Post-traumatic C1-C2 rotational subluxation in pediatric age is a very frequent event. It mimics benign torticollis but may result in permanent disability. The atlanto-axial rotatory displacement, as defined initially by Fielding and Hawkins in 1977, is classified into four types: Type 1 is the most common form in children. It is a simple rotatory displacement without an anterior shift. Type 2 is potentially more dangerous. It is a rotatory displacement with an anterior shift of 5 mm or less. Type 3 is rotatory displacement with an anterior shift greater than 5 mm. Finally, type 4 is rotatory displacement with a posterior shift. Type 3 and 4 deformities are rare, but neurological involvement or even instant death may follow [Fig. 4] (18). The condition requires prompt diagnosis by thorough examination to avoid any treatment delays. The difficulties for a timely and correct diagnosis and then the correct treatment are described. Case presentation: A 5 year old girl comes to the emergency room with cervical pain and stiffness.This painful state, as mum reports, has been lasted for about ten days, after a mild trauma. The radiographic picture demonstrates a rotary subluxation C1-C2, type 1 according to Fielding and Hawkins classificationThe treatment is head-halter traction with 2kg, and nonsteroidal anti-inflammatory drugs (NSAIDs) . After 2 days the x-ray picture improves, but the painful symptoms persist. An in-depth diagnostic MRI of the cervical spine and brain revealed a medulloblastoma which made an immediate and effective neurosurgical intervention necessary. Conclusions: the C1-C2 rotatory dislocation must always be evaluated with extreme care, without neglecting any clinical and anamnestic information for a correct and timely differential diagnosis. Remember that children show very clearly what they feel, always .