Block vertebra – A commonly seen uncommon anomaly on lateral cephalogram

Abstract

Lateral cephalogram as a diagnostic aid in orthodontics many a times showcases asymptomatic undiagnosed anomalous findings that may or may not be associated with syndromes. Orthodontist may be the first one to detect anomalous cervical vertebrae (CV) as being visible in lateral headfilm. Block vertebrae (BV) is one of those uncommon anomalies with the incidence ranging from 0.25% to 6.25% among various populations with CV being most commonly involved that may radiographically depict “wasp waist sign.” The condition occurs due to defective segmentation of sclerotomes during postsomite period of embryonic development. BV usually remains asymptomatic but in some instances may be associated with early degenerative changes. Therefore, the role of orthodontist in early detection of the condition may be beneficial for patients in the long run.