title: Posterior arch defects of the cervical spine.
abstract: Spondylolysis and absence of the pedicle are congenital anomalies of the posterior cervical spine. Their roentgenographic changes may be confused with other more serious entities which may necessitate either emergent therapy or require extensive diagnostic testing and treatment. Four cases are present and the literature is reviewed. A hypothesis for the embryologic etiology of these entities is proposed.
mesh_terms: D000293:Adolescent; D000328:Adult; D002574:Cervical Vertebrae / Q000002:abnormalities / Q000000981:diagnostic imaging*; D002648:Child; D006801:Humans; D008297:Male; D011859:Radiography; D016136:Spina Bifida Occulta / Q000000981:diagnostic imaging; D013168:Spondylolisthesis / Q000000981:diagnostic imaging*; D013169:Spondylolysis / Q000151:congenital / Q000000981:diagnostic imaging*