Inca bones are accessory bones found in neurocranium of human skulls. Occurrence of Inca bones is rare as compared to other inter sutural bones such as wormian bones. These Inca ossicles are regarded as variants of the normal. The reporting of such occurrences is inadequate from Central India.Objectives:To find the incidence of Inca variants in Central India.Materials and Methods:In the present study, 380 dried adult human skulls were examined. All specimen samples were procured from various Medical colleges of Central India. They were analyzed for gross incidence, sexual dimorphism and number of fragments of Inca bones.Results:Gross incidence of Inca bones was found to be 1.315 %. Incidence rate was higher in male skulls than female skulls (male: 1.428%; female: 1.176%). The Inca bones frequently occurred signally. Out of the five observed Inca ossicles, two were fragmented.Conclusions:This data gives idea regarding gross incidence, sexual dimorphism and number of fragments of Inca bones in neurocranium of human skulls from Central India. The knowledge of this variable is useful for neurosurgeons, anthropologists and radiologists.

The musculocutaneous nerve usually branches out from the lateral cord of brachial plexus. It innervates the corcobrachialis, biceps brachii and brachialis muscles and continues as the lateral cutaneous nerve of forearm without exhibiting any communication with the median nerve or any other nerve. We report unilateral variation in motor innervations of the left arm in a 58-year-old male cadaver. The musculocutaneous nerve was found to be absent. A muscular branch of the median nerve was supplying the coracobrachialis muscle. In the middle of arm, the median nerve was found to be branching out, bifurcating and supplying the long and short head of biceps. The median nerve was found to be giving a separate branch, which supplied the brachialis muscle and continued as the lateral cutaneous nerve of forearm. The right sided structures were found to be normal. Surgeons should keep such variations in mind while performing arm surgeries.

Radial nerve is usually a branch of the posterior cord of the brachial plexus. It innervates triceps, anconeous, brachialis, brachioradialis, extensor carpi radialis longus muscles and gives the posterior cutaneous nerve of the arm, lower lateral cutaneous nerve of arm, posterior cutaneous nerve of forearm; without exhibiting any communication with the medial cutaneous nerve of forearm or any other nerve. We report communication between the radial nerve and medial cutaneous nerve of forearm on the left side in a 58-year-old male cadaver. The right sided structures were found to be normal. Neurosurgeons should keep such variations in mind while performing the surgeries of axilla and upper arm.

Journal of College of Medical Sciences-Nepal, 2011, Vol-7, No-2, 49-54DOI: http://dx.doi.org/10.3126/jcmsn.v7i2.6681