title: Spondylolysis of the lumbar spine: demonstration of defects and laminal fragmentation.
abstract: Fifty-six cases of spondylolysis were encountered in 1500 lumbar spine reports reviewed. The frequency of detecting isthmus defects on anteroposterior (AP), lateral, 45-degree right and left oblique, 30-degree up-angled AP, and collimated lateral views was determined. The collimated lateral view showed the largest number of pars defects, 84% of cases. The 30-degree up-angled AP view was more sensitive than the AP view, showing 55% versus 32% of cases. A previously unreported sign of spondylolysis, fragmentation of lamina demonstrated on the AP or AP up-angled view, was found in 14.2% of cases of spondylolysis.
mesh_terms: D005260:Female; D006801:Humans; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging*; D008297:Male; D008722:Methods; D011859:Radiography; D013168:Spondylolisthesis / Q000000981:diagnostic imaging*; D013169:Spondylolysis / Q000000981:diagnostic imaging*