Asked by Napoli
In children younger than 8 years, the C2-C3 space or occasionally C3-C4 space can have a normal physiological displacement in lateral flexion and extension views radiographs of cervical spine. It can occur in upto 40%.
To distinguish pseudosubluxation from traumatic subluxation:
1. Draw a posterior cervical line between the spino-laminar lines of C1 and C3.
2. This line should pass through or be less than 2mm anterior to the C2 spino-laminar line to be considered physiological.
3. If the distance is >/= 2 mm, the subluxation must be considered traumatic.
4. Pseudosubluxation is exaggerated with the neck flexed and reduced with neck extension.
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Swischuk's line |