Light Microscopic Study of The Lumbar Intervertebral Disc Showing Inherent Difference Between Anterior & Posterior Annulus Fibrosus - A Risk Factor For Posterior Disc Herniation.

The present study is based upon the light microscopic observations made on the foetuses to determine the structural discrepancy in anterior and posterior annulus fibrosus in the development of human foetal lumbar intervertebral disc. A morphological comparison of the structure of anterior and posterior annulus fibrosus was made to consider the arrangement of lamellar bundles. As the foetus advances in age, the anterior annulus fibrosus becomes thicker than the posterior annulus. A very intricate structure was observed in posterior annulus with large number of loose and discontinuous lamellar bundles and more fibre-interlacing angles. Loose connection of the lamellar bundles in posterior annulus of almost all the foetuses indicates an inherent weakness which may lead to posterior rupture of the disc in later life.

Undivided Retromandibular Vein Continuing As External Jugular Vein With Facial Vein Draining Into It : An Anatomical Variation.

Despite the fact that the blueprint of the whole body is unravelled, faultlessly during the growth and development of an animal; but amazingly variations do occur. During routine dissection of head and neck in a middle aged cadaver in the Post Graduate Department of Anatomy of this medical college, we found variation in the formation of external jugular vein on both sides, which was formed by the continuation of undivided trunk of retromandibular vein. The facial vein and posterior auricular vein were the tributaries of external jugular vein. The sound anatomical knowledge of variations of the veins of head and neck is essential to the success of surgical procedures. The embryological evaluation of the above anomaly was done and compared with the available literature which showed that the observed variation was rare.

Higher Bifurcation of Brachial Artery with Superficial Course of Radial Artery in Forearm.

An unusual case of bilaterally symmetrical higher bifurcation of brachial artery into radial and ulnar arteries with superficial course of radial artery in right forearm is reported. Accurate information regarding these variations is important during vascular and re-constructive surgery and also in evaluation of angiographic images.