Incidence, morphology and clinical relevance of bony canals and vascular grooves in the paracondylar region of adult human skulls

Most features of the skull are well described in standard anatomy textbooks. There may, however, be variations in the form of minor grooves, canals and foramina that merit documentation. In the present study, morphological diversity in the form of osseous tunnels was seen adjacent to the occipital condyles. These canals were present in the paracondylar region (lateral to the occipital condyle) and are therefore termed paracondylar canals. A total of 304 dry adult human skulls (608 sides) of Indian origin were examined and paracondylar canals were found in 59 of these. Thirty-six (11.8%) were bilateral and 23 (7.6%) unilateral. Vascular grooves were found leading to the canals in 52 sides (15.8%). This may result from normal developmental processes and could be a peculiarity confined to the Indian population, as it has not been reported previously. This variant may serve as a valuable anthropological marker. The results of surgical procedures in this area, such as the paracondylar approach (which is directed through the area lateral to the occipital condyles) and the far lateral supracondylar approach, could be impacted upon by this variation.