Radiological sign of spondylolysis?: (A) Napoleon's hat sign, (B) 'Scottish dog with collar' sign, (C) Winking owl sign, (D) 'Cap' sign
Answer is B. Ans BIn spondylolysis on oblique view scotty dog with collar is seen while in spondylolisthesis inverted napoleon hat sign (AP view L5 over S1) and scotty dog with broken neck sign (oblique view) are seen.