Anatomical evaluation of the posterior condylar canal: a study on dry adult Thai skulls.

Abstract

Background: The posterior condylar canal (PCC) is a crucial structure facilitating venous drainage from the intracranial venous sinuses to the extracranial system. This study aimed to provide anatomical insights into the PCC's prevalence, location of the extracranial and intracranial orifice and diameter, aiding surgical procedures involving the posterior skull base, foramen magnum, and jugular foramen.

Materials and methods: Two hundred dry skulls (100 male and 100 female) were examined. The PCC was traced using a flexible wire through its extracranial orifice. Its location was categorized relative to the posterior edge of the occipital condyle (PEOC) into lateral, middle, or medial thirds. The intracranial orifice was classified as intrajugular, intrasinus, or retrosinus. The maximum diameter of the extracranial orifice was measured.

Results: The PCC was present in 79.5% of skulls, with bilateral occurrence in 39.5%, right unilateral in 22%, and left unilateral in 18%. In 20.5% of cases, the PCC was absent. A double PCC was observed in a single skull. No statistically significant difference in PCC prevalence was found between sexes. The extracranial orifice was most commonly located in the lateral third of the PEOC (41.4%). The most prevalent intracranial orifice type was intrajugular (46.6%). The average PCC diameter was 3.77 ± 1.0 mm. No statistically significant difference was observed between sides in either extracranial location or intracranial orifice type.

Conclusion: Understanding the anatomical variations of the PCC is clinically important for radiologists in interpreting pathological conditions and for neurosurgeons in planning surgeries involving the occipital condyle region.