Cervical subaxial spine uni-facet dislocation occurring in an infant

While pediatric spinal injuries account for between 1 and 10% of all spinal injuries <1% occur in the infant population. In this age group the mechanism of injury described is specific with by far the majority occurring in motor vehicle accidents and in the context of non-accidental injury syndrome. A further characteristic of infant cervical spine injuries is that over five times as many involve the cranio-cervical junction compared to the sub-axial cervical spine. As such this case report gives an account of a very rare occurrence namely an infant whom after an innocuous fall incurred a right cervical C6/C7 uni-facet dislocation. A six month old male infant presented to our unit with the history that the child had fallen down two stairs whilst in his walker. The child's mother reported that since the event the child was irritable and had pain in his neck that seemed to be getting worse. Examination of the infant's neck revealed a 10 degree rotational deformity to the left and lower cervical posterior midline tenderness. There was no obvious step palpable. The rest of his neurological examination was normal. A computed tomographic scan of his cervical spine confirmed a left C6/C7 unifacet dislocation. The unifacet dislocation was successfully reduced under conscious sedation, using a halter, with serial imaging being performed. A post-reduction MRI confirmed the successful reduction and excluded cord compression. The infant was placed in a rigid cervical collar for 3 weeks and re-imaged with flexion/extension views. Fortunately the infants imaging excluded instability and he made a full recovery. In conclusion this case report gives an account of a sub-axial cervical spine injury pattern commonly seen in adults and very rarely encountered in infants. Closed reduction and a cervical brace were used to successfully manage this very rare injury.