Atlantoaxial rotatory subluxation/fixation and Grisel's syndrome in children: clinical and radiological prognostic factors.

Atlantoaxial rotatory subluxation/fixation (AARS/F) is a rare cause of torticollis in children. The aim of our study is to investigate all possible clinical and radiological prognostic factors in children with AARS/F. We retrospectively reviewed all cervical spine CT scans of children with AARS/F treated in our Hospital over the last 15 years. AARS/F was classified according to Fielding and Hawkins classification and C1-C2 rotation-degree was calculated. Moreover, two orthopedic surgeons reviewed all clinical reports of these children. All patients were conservatively treated (cervical traction/neck collar). An early recovery was considered in patients with complete clinical/radiological healing at 3 months follow-up, while a late recovery was considered in patients with disease persistence or relapse at 3 months follow-up or earlier. Fifty-five patients with diagnosis of AARS/F were included in the study (mean age = 8.5 years old - 25F, 30M). In 9/55 subjects (16.4%), a late recovery was observed. The presence of a concomitant infection or inflammation in the head and neck region (Grisel's syndrome) was significantly associated with a late recovery (p < .001). Also, the type of AARS/F (p = .019), according to the Fielding and Hawkins classification, and C1-C2 rotation-degree (p = .027) were significantly correlated with the recovery time.Conclusion: In patients with AARS/F, the presence of a concomitant infection/inflammation in the head and neck region is the most important prognostic factor and it is associated with a late recovery. The Fielding and Hawkins classification and C1-C2 rotation-degree well correlate with patients' recovery time. What is Known: • Atlantoaxial rotatory subluxation/fixation (AARS/F) is a rare cause of torticollis in children and CT is the most useful imaging tool for diagnosis and classification of AARS/F. • Conservative treatments are effective in the majority of pediatric patients with AARS/F. What is New: • The presence of a concomitant infection/inflammation in the head and neck region associated with AARS/F (Grisel's syndrome) is the most important prognostic factor and it is associated with a late recovery. • C1-C2 rotation-degrees, as well as Fielding and Hawkins classification system, well correlate with patients' recovery time.