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A case of familial paediatric atlantoaxial subluxation.

INTRODUCTION
Fixed atlantoaxial rotary subluxation (FAARS) is a rare cause of torticollis in children. Familial FAARS has not been described in the literature previously. We present case reports of two siblings who both developed spontaneous atlantoaxial rotary subluxation and discuss the possible causes. Both patients were treated conservatively and made a successful recovery.


METHODS
The notes and images of two siblings were reviewed following permission from their parents. A literature search was also performed to look at what is currently known about atlantoaxial subluxation.


RESULTS
Both siblings were successfully treated with halter traction and subsequent collar treatment. Os terminale was iden- tified on the CT images of both children.


CONCLUSIONS
Atlantoaxial rotary subluxation should be considered as a cause of torticollis in children and can occasionally occur spontaneously. Both siblings had os terminale and it raises the possibility that this may predispose children to develop- ing FAARS. There may also be an underlying previously unidentified familial cause. Appropriate imaging followed by prompt treatment in halter traction is usually successful. If a diagnosis of FAARS is confirmed in a paediatric patient, the clinician should have a high index of suspicion when a sibling presents with torticollis or associated neck pain subsequently.