Variant Patterns Of Brachial Plexus – A Cadaveric Study In North Indian Population

Background: The brachial plexus is constituted by the ventral rami of C5-T1 spinal nerves. It forms a network ofterminal nerves that innervate the upper limb. Variations of brachial plexus are common and a better awarenessof variations is very crucial to achieve successful results in its surgical procedures. The aim of present studywas to find the variant patterns of brachial plexus and to discuss their developmental and clinical significance.Materials and Method: 50 upper limbs belonging to 25 formalized and well preserved male cadavers obtainedfrom the Department of Anatomy, constituted the material for the study. These were dissected and roots, trunks,cords and terminal branches of brachial plexus were exposed. The variant patterns were noted and photographed.Results: Out of 50 limbs, 5 limbs showed variations of brachial plexus at different levels.All the variations seenwere unilateral. Out of 5 variant patterns seen, different types of communications between musculocutaneousand median nerve were observed in 4 limbs (8%).Out of 4, in 1 limb (2%) medial cord joined with lateral root ofmedian nerve to form mediano-ulnar nerve which after a distance of 1cm bifurcated into median and ulnarnerve. In one limb (2%), there was no distinction between medial and lateral cord. Instead a single anterior cordwas formed by union of anterior divisions of all the three trunks anterior to axillary artery.Conclusion: The variant patterns of brachial plexus are usually more prone to accidental injuries and entrapmentneuropathies. Knowledge of such variations may provide additional anatomical information for the cliniciansduring diagnosis of unusual clinical symptoms and also for surgeons during surgical exploration of axilla andarm to avoid damage to these nerves.

Accessory belly of piriformis, as a cause of superior gluteal neurovascular entrapment.

During routine dissection on 50 years old male cadaver, an accessory belly of piriformis was observed. This accessory belly was superior and parallel to the main piriformis muscle. This was associated with emergence of superior gluteal nerve and superior gluteal artery between the two bellies. Piriformis muscle and its relation to sciatic nerve has been suggested as a cause of piriformis syndrome. But interestingly in the present case, superior gluteal nerve was interposed between two bellies that may help the clinicians to establish a rare yet important cause of piriformis syndrome and a rare cause of undiagnosed chronic pain in gluteal region. As superior gluteal artery was also interposed, so this rare variation holds interest to surgeons especially in isolated buttock claudication despite otherwise normal vascular investigations.

Cranial Anthropometry in 600 North Indian Adults.

The present study was conducted on 600 adults, comprising of equal number of males and females, within the age group of 18 year and above and of North Indian origin. The purpose of study was to access the head length, head width and to find out the relationship of these parameters with each other. Cephalic Index was calculated. The data so obtained was compiled and analysed statistically to observe baseline data and then compared with previous available data. This data can be useful for experts in forensic and allied surgical branches. The average head breadth and head length found in study were 139.51 mm, 186.88 mm respectively in males and 136.19 mm, 177.74 mm respectively in females. On the basis this study it was concluded that North Indian males have dolichocephalic type of head and females have mesocephalic type of head.