Abstract:
The suboccipital triangle (ST) is a clinically relevant landmark in the posterior aspect of the neck and is
used to locate and mobilize the horizontal segment of the third part of the vertebral artery before it enters the cranium.
Unfortunately, this space is not always a viable option for vertebral artery exposition, and consequently a novel triangle,
the inferior suboccipital triangle (IST) has been defined. This alternative triangle will allow surgeons to locate the artery
more proximally, where its course is more predictable. The purpose of this study was to better define the anatomy of both
triangles by measuring their borders and calculating their areas. Ethical clearance was obtained from the University of
Pretoria (reference number: 222/2021) and both triangles were subsequently dissected out on both the left and right sides of
33 formalin-fixed human adult cadavers. The borders of each triangle were measured using a digital calliper and the areas
were calculated using Herons Formula. The average area of the ST is 969.82±153.15 mm2
, while the average area of the IST
is 307.48±41.31 mm2
. No statistically significant differences in the findings were observed between the sides of the body,
ancestry, or sex of the cadavers. Measurement and analysis of these triangles provided important anatomical information
and speak to their clinical relevance as surgical landmarks with which to locate the vertebral artery. Of particular importance
here is the IST, which allows for mobilisation of this artery more proximally, should the ST be occluded.
