Characterization of Occipital Condyle and Comparison of its Dimensions with Head and Foramen Magnum Circumferences in Dry Skulls of Iran

Abstract

SUMMARY:The occipital condyle (OC) is an important area in craniovertebral surgery, but its anatomical features and the procedures concerning the OC have not been studied in detail yet. The aim of this study was to revisit the anatomy of the occipital condyle region and assess variations of the surrounding structures. Observations, on fifty dry skulls (dried specimens, 100 sides) and determined of condyle measurements. The mean length, width and height of occipital condyle were found to be 19.43±3.27 (right), 19.28±3.57 (left), 9.21±1.97 (right) 9.40±1.87 (left), 7.21±1.9 (right) and 7.33±2.74 mm (left), respectively. There were significant differences between right and left occipital condyles. The mean anterior intercondylar distance and posterior intercondylar distance were measured as 15.39±7 and 35.60±8.4 mm, respectively. Variations of occipital condyle shapes were kidney like (34.4%), S-like (25.6), triangular (13.3%) oval (10.0%), ring like (7.8%), eight like (6.7%) and deformed (2.2%) respectively. The condylar fossa presented in 60% of dry skull, 24% in right side and 36% in left side and also the condylar foramen was found in 60% of the specimens studied. There was no relation between the circumference of the head and the length of OC but we found relation between the circumference of the head and the width of OC (0.527) and foramen magnum circumference (0.433). The OC and FM are the main bony structures obstructing the surround of the brainstem. The differences in the size and the shape of occipital condyle have some differences and also similarities among racial subgroups. The posterior condylar vein may act asymmetrically. The correlation of the size of foramen magnum with the width of occipital condyles shows the importance of occipital condyle for lateral movements besides antero-posterior movements.

Morphometry of Occipital Condyles in Craniovertebral Surgeries

“…In a study by Bayat et al [1], the mean length of left occipital condyle was 19.28 mm and right occipital condyle was 19.43 mm. These findings were observed lesser than our present study findings.…”

“…near the foramen magnum will be the dorsal approach [1]. Different procedures are adapted by the neurosurgeons to minimise the morbidity like lateral, transcondylar approach [1,2].…”

“…Different procedures are adapted by the neurosurgeons to minimise the morbidity like lateral, transcondylar approach [1,2]. During this procedure the occipital condyle is resected fully or partially.…”

Morphometry of the Occipital Condyle and Basilar Process of Nigerian Skulls

“…This study observed that for both males and females, the left and right OC length and MxOC width were significantly different; with the left being greater than the right, However the MnOC width was bilateral. Asymmetry in OC dimensions has been reported by Agnihotriet al (2014), [20] and Bazyatet al (2014), [18] in which they stated that the right OC parameters had mean values significantly greater than the left; however, Lang (1995), [33] Cicekcibasiet al (2004), [8] and Tale et al's (2016), [34] reported no significant bilateral differences in the condyle parameters. The hypothesis of difference in data acquisition (radiologic, osteometric and photogrammetric) report by Lang and Hornung (1993), [23] inconsistencies in collection methods (Bozbugaet al, 1999), [15] and genetic endowment (Le et al, 2011;Yu et al, 2015); [13,14] as well as racial/ethnic differences (Lang and Hornung, 1993;Lang, 1995;Bozbugaet al, 1999;Cicekcibasiet al, 2004), [8,15,23] are undoubtedly factors which could impact on the range differences in the value obtained in morphometric studies.…”

“…[5][6][7][8] The occipital condyle (OC) and basilar process (BP) are structures located at the skull base which forms part of the floor of the cranial cavity which by location, differentiates the brain from facial structures and suprahyoid neck (Rautet al, 2012). [9] Name & Address of Corresponding Author Aigbogun (Jr) [8,13,14] with higher values reported for the Asians (Bozbugaet al, 1999; Yu et al, 2015; Salujaet al, 2016), [14][15][16] and lower values for the Caucasians and Australians (Wen et al 1997;Bazyatet al, 2014), [17,18] while for Africans the values fall between values of Asians and Caucasians (Salihet al, 2014; Agnihotriet al, 2014). [19,20] Only a few studies have reported morphometric values for the basilar process (clivus), with dimensions ranging from 24mm to 27mm (Oliviera, 1975; Wescott and Moore-Jansen, 2001), [21,22] and higher values for whites when compared to blacks (Wescott and Moore-Jansen, 2001).…”