title: Radiography of the hyperextended lumbar spine: an effective technique for the demonstration of discal vacuum phenomena.
abstract: A prospective evaluation of dynamic lateral lumbar spine radiographs in the erect position in 52 symptomatic patients over the age of 50 years revealed vacuum phenomena in intervertebral discs in 46%. Their frequency was greatest at the L5-S1 spinal level and decreased progressively at higher lumbar levels. Analysis of the dependency of discal vacuum phenomena on spinal position during radiography revealed that hyperextension detected all such phenomena; radiography in the neutral position detected 73% of vacuum phenomena, whereas that obtained with the spine flexed revealed 20% of vacuum phenomena. Our results indicate that lateral radiographs of the hyperextended lumbar spine are useful in the differential diagnosis of intervertebral osteochondrosis (degenerative disease of the nucleus pulposus) and infection.
mesh_terms: D000368:Aged; D003937:Diagnosis, Differential; D005260:Female; D005740:Gases; D006801:Humans; D007403:Intervertebral Disc / Q000000981:diagnostic imaging*; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D010007:Osteochondritis / Q000000981:diagnostic imaging*; D011187:Posture; D011446:Prospective Studies; D011859:Radiography; D013122:Spinal Diseases / Q000000981:diagnostic imaging*
chemical_list: D005740:Gases