Which of the following is the least useful for diagnosis of Spondylolisthesis?
(A) CT (B) MR (C) X-ray lumbar spine- AP view (D) X-ray lumbar spine- Lateral view
(C) Ans. c. X-ray lumbar spine- AP view (Ref Tureks 6/e p503; Maheshwarl 3e/p 237; Wolfgang 7/e p 228-29, 206; Sutton 7/e p/66'Although for imaging of spondylolisthesis usually all are done, AP view appears to be least useful of these choices. On AP view, spondylolisthesis can show a sign called Napolean Hat sign. The lateral view is useful in detecting spondylolisthesis; it may demonstrate the pars defect.Spondylolisthesis is forward slip of one veebrae upon another; so it is best viewed (or seen earliest) in sagittal images of spine i.e. lateral and oblique X-ray of spine and saggital and axial views of CT and MRIQ