Accessory Transversarium Foramen of Cervical Vertebrae: A Case Study

Abstract

The anatomical variations of the cervical vertebrae as reported in most classical anatomical textbooks mainly include: cervical ribs, non fusion of the halves of the posterior arch of the atlas, presence of articular facets on the superior margin of the anterior arch of the atlas incase of presence of a third occipital condyle. A male cadaver preserved by means of the routine embalming techniques following the completion of dissection was used for bone maceration. The soft tissues were removed and the cervical vertebrae were studied for variations. The variations recorded in this study include the presence of accessory transverse foramina in the atlas, C5 and C6, The presence of an accessory foramen transversarium in the cervical vertebra is a rare variation. It narrowed the size of the real transverse process and this may result in pressure on the vertebral artery and the sympathetic plexus embedding it. Similarly the narrowing of the transverse foramen may result in formation of atheromatose plaque which may also result to thrombosis emboli or just reflex spasm. The implications of these variations in the anatomy of this region should be noted by neurologist and by those who advocate instrumentation of the cervical vertebrae.

Key words: Cervical vertebra, Atlas, Accessory transverse foramina, Foramen transversarium