Morphological Analysis on the Occipital Condyles and Review of the Literature

Abstract

SUMMARY:Most anatomical and biomechanical studies on the craniovertebral junction have involved morphological or morphometric analysis on the occipital condyles. Some of these studies have provided important findings based on different surgical procedures. The shape, size and angle of the occipital condyles and the locations of the intracranial and extracranial orifices of the hypoglossal canal are highly important because they may affect the lateral approaches to the craniovertebral junction. To determine the frequency of occurrence of different morphological types of occipital condyle. 214 occipital condyles in 107 dry human skulls were analyzed and the classification of their morphological types was determined through assessing digitized photographic images. Among the 107 skulls analyzed, 59.8 % were male and 40.2 % were female. Their ages ranged from 11 to 91 years, with a mean of 57.56 years. Of the total of 10 morphological types of occipital condyle that were found, more than 50 % were of the "8", "S" and ring types. Condyles of "8" and "S" shape were the main types found in male skulls: the "8" shape prevailed on the left side and the "S" shape on the right side. However, in female skulls, these two types had equal bilateral distribution.

Morphological analysis and morphometry of the occipital condyle and its relationship to the foramen magnum, jugular foramen, and hypoglossal canal: implications for craniovertebral junction surgery

“…The most prevalent shape of OC in this study was oval-like condyle or type I, which agreed with previous findings in Indians [ 14 , 19 , 26 ], and Turks [ 20 , 27 ]. In contrast, Aragão et al [ 13 ] and Bayat et al [ 28 ], reported that the most common shape in Brazilians was S-like condyle or type III and kidney-like condyle or type II in Iranians. The prevalence of OC shape may be related to ethnicity.…”

“…This process increases the angle of exposure, greater visualization, and enhances access to the ventrolateral and ventral aspects of CVJ [ 5 , 11 , 12 ]. The morphological or morphometric analysis of OC has been described in a majority of CVJ anatomical and biomechanical studies [ 1 , 13 - 15 ]. The stability of CVJ depends mainly on the length of OC.…”

Bioanthropological analysis of human occipital condyles using geometric morphometric method

“…They analyzed 10 types of occipital condyles where three types (type 8, type S and ring type) were present in 50% of the examined occipital condyles. In male skulls, type 8 dominated on the left occipital condyles and type S on the right occipital condyles, while on female skulls these two types (type 8 and type S) were equally represented on both side ( Aragao et al, 2017 ).…”