Bony Tubercle on the Posterior Border of Foramen Magnum - A Case Study

Presence of tubercles in the foramina of the cranium has aroused the curiosity of anatomists. The foramen magnum is the large opening situated in the occipital bone, and transmits important neurovascular structures. During routine study of skull in the department of Anatomy at DM Wayanad Institute of Medical Sciences, Meppadi, Kerala, a triangular projection was found at the posterior margin of foramen magnum, with the apex directed forwards towards the anterior margin of foramen magnum. The tubercle measured 1.5mm antero-posteriorly and 1.5mm transversely.