Introduction A physiologic (normal) pseudosubluxation of cervical vertebrae of up to 40% (or 4 mm) seen in young children. Epidemiology incidence around 20% of children admitted for polytrauma will demonstrate this incidental finding no associations with gender, trauma, intubation status or injury severity have been demonstrated demographics seen in children less than 8 years location C2 on C3 is most common C3 on C4 is second most common Pathophysiology caused by the horizontal nature of the facet joints at younger ages facet joints become more vertical with age Imaging Radiographs recommended views lateral radiograph with flexion and extension findings reduction of subluxation with extension xrays absence of anterior soft-tissue swelling (usually seen with traumatic cause) measurements Swischuk's line spinolaminar line drawn from spinolaminar point on C1 to C3 spinolaminar point on C2 should be within 1.5 mm of spinolaminar line helpful to differentiate pseudosubluxation from true injury Differential True traumatic subluxation factor that support pseudosubluxation as opposed to true traumatic subluxation include reduction of subluxation with neck extension spinolaminar line within 1.5mm of C2 no history or physical findings of significant trauma absence of anterior soft-tissue swelling true traumatic subluxation may be caused by Hangman's fx Treatment Nonoperative observation indications psuedosubluxation outcomes no association with increased morbidity or mortality has been associated with this condition
QUESTIONS 1 of 1 1 Previous Next (OBQ08.169) A lateral radiograph of a 5 year-old child with no history of trauma is shown. The deformity reduces on extension radiographs. What is the most likely diagnosis. Review Topic QID: 555 FIGURES: A 1 Traumatic spondylolisthesis of axis 1% (23/3055) 2 Pseudosubluxation of the cervical spine 93% (2854/3055) 3 Atlantoaxial instability (AP) 3% (77/3055) 4 Rotatory atlantoaxial instability 1% (23/3055) 5 Klippel-Feil Syndrome 2% (56/3055) ML 1 Select Answer to see Preferred Response PREFERRED RESPONSE 2