Presentation
Work up for low back pain.
Patient Data
Age: 20 years
Gender: Female
From the case:
Collar sign in spondylolysis
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There is a break in the left pars interarticularis of the L4 vertebra on the oblique radiograph that resembles a collar around the Scotty dog's neck.
A suspected break is also noted in the left pars interarticularis of the L5 vertebra.
Case Discussion
The Collar sign in spondylolysis refers to a break in the pars interarticularis of the vertebra on oblique radiographs that could be seen as unilateral or bilateral.
About 90% of spondylolysis were seen at the L5 level, and less than10% were noted at the L4 level if bilateral 65% of patients may progress to spondylolisthesis.