Partial regressive occipital vertebra.
Craniocervical developmental anomalies can be quite varied and many involve the proatlas and its remnants. A previously undescribed variant consisting of a remnant of the proatlas and its transverse processes is reported and the developmental anatomy of this region is summarized.
D000328:Adult; D002574:Cervical Vertebrae / Q000002:abnormalities* / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D009777:Occipital Bone / Q000196:embryology*; D011859:Radiography; D012886:Skull / Q000000981:diagnostic imaging