Beheaded Scottish terrier sign is seen in
High-Yield Explanation
Optimal view for visualizing (spondylolysis) defect is=X-ray spine oblique view: - Scotty dog with "broken collar or neck" = Spondylolysis. - Beheaded Scotty dog = Spondylolisthesis. Oblique radiograph of lumbar spine is best view for radiographic diagnosis of spondylosis. Note the description of Scottish dog appearance as seen on oblique LS spine view and classical spondylolysis: