Morphometric analysis of the bony structures associated with the transcondylar approach (915.15)

Varying approaches to the foramen magnum are essential for access to the area, therefore understanding the bony anatomy of this region is important for the surgery. The aim of this study is to conduct a morphometric analysis of the jugular tubercle, occipital condyle, and lateral mass of C‐1, since these bony landmarks are the main obstacles hindering visualization of the clivus. Thus we have conducted a morphometric analysis in 35 adult dry skulls and C1 vertebrae. The distances on left (L) and right (R) sides were measured in millimeters. The distances were; between the anterior part of the occipital condyle to the jugular tubercle (L: 14.54± 0.36, R: 14.88 ± 0.37); from the mid part of the occipital condyle to the jugular tubercle (L: 14.43±0.33, R: 14.92±0.34), from the posterior part of the occipital condyle to the jugular tubercle (L: 9.81±0.35), R: 11.39±0.3), from the anterior part of the occipital condyle to the basion (L: 24.26±0.36, R: 24.04±0.33), from the posterior part of the occipital condyle to the basion (L: 11.36±0.25, R: 10.81±0.31) and from the jugular tubercle to the basion (L: 18.21± 0.24, R:17.56 ±0. 57). We also documented the width of lateral mass horizontally (L: 11.42±0.37, R: 11.08±0.35) and vertically (L: 19.65±0.41, R: 18.9±0.42) and the thickness of the anterior part of the occipital condyle (L: 8.82±0.18, R: 10.82±0.23), the thickness of the mid part of the occipital condyle (L: 10.42±0.28, R: 9.23 ±0.18) and the thickness of the posterior part of the occipital condyle (L: 8.42±0.16, R: 8.59±0.20). This study provides morphometric measurements of the bony landmarks for the transcondylar and its modified approaches to the foramen magnum and related structures.