Ponticulus posticus on the Posterior Arch of Atlas, Prevalence Analysis in Asymptomatic Patients

Abstract

The Ponticulus posticus is a bony bridge located in the posterior arch of the atlas in relation to the passage of the vertebral artery. Its presence has been associated with development of cervical pain and cerebrovascular disorders. The purpose of this study was to assess its prevalence in asymptomatic patients. We examined 436 digital teleradiographs of patients aged from 5 to 70 years (mean of 18.44 years, SD. 9.59) of both sexes (173 men, 263 women). In 80.7% (n = 352) of cases, no radiographic evidence of ossification was found; 19.3% showed some degree of ossification, of which 10.1% had partial ossification and 9.2% complete ossification. The prevalence of complete ossification was slightly higher in women than in men and occurs in all the age groups analyzed. Our results suggest that the Ponticulus posticus is an anatomic condition with a protective function.

Prevalence and Morphologic Characteristics of Ponticulus Posticus: Analysis Using Cone-Beam Computed Tomography

“…The PP, which seems to be the consequence of the complete or incomplete ossification of the posterior atlantooccipital membrane over the vertebral artery groove, 21 has become a significant abnormality of the atlas in the management of atlantoaxial instability, which has gained popularity. 10,48 Therefore, developmental anomalies of the atlas are of interest not only to anatomists but also to clinicians, radiologists, surgeons, and chiropractors, who should be aware of their distinct morphological manifestations as well as correlated clinical expressions. [49][50][51] The PP is generally regarded as a simple anatomical variant.…”

Ponticulus Posticus: Is It Important for a Dentist as an Radiological Finding?

“…10 PP has been documented in children as young as two years old and thus some authors 23,24 have commented that this structure is simply a regressive and disappearing morphological phenomenon. According to Schilling et al 3 presence of the PP is a condition independent of age, and therefore should not be considered a calcification or an ossification of the lateral segment of the posterior atlantooccipital ligament, but rather an ossification with functional significance, developed in other primates 19 in order to protect the passage of the vertebral artery in a region which, by its sinuosity, is susceptible to being damaged or compressed as a result of craniocervical dynamics (Figure 4). 3 On the other hand, PP has been described in classical literature as an anatomical variation that originates in the ossification of the lateral segment of the posterior atlantooccipital ligament or the capsule of this joint.…”

“…The PP means "little posterior bridge" in Latin 3,6,[8][9][10][11][12][13][14][15][16][17][18] which describes an anomalous malformed bony bridge between the posterior portion of the superior articular process and the posterolateral portion of the superior margin of the posterior arch of the atlas. 9 The normal atlas ( Figure 1) is a ring-like structure consisting of two lateral masses connected by a short anterior arch and a longer posterior arch.…”

“…5,6 (Table 1), however, its most accepted name is PP. 3,4 Its origin, embryology, prevalence, clinical significance, and implications are all without definitive answers. Records of its descriptions have been found dating back to the 1800's.…”

“…2 The ponticulus posticus (PP), foramen arcuale or "Kimmerle's anomaly" is a poorly understood anomaly of the atlas vertebrae. 3,4 The PP, which seems to be the consequence of the complete or incomplete ossification of the posterior atlantooccipital membrane over the vertebral artery groove, has become a significant abnor-7tepeklinik mality of the atlas in the management of atlantoaxial instability, which has gained popularity. Therefore, developmental anomalies of the atlas are of interest not only to anatomists but also to clinicians, radiologists, surgeons, and chiropractors, who should be aware of their distinct morphological manifestations as well as correlated clinical expressions.…”