Study of Sacral Hiatus in Dry Human Sacra in Nepal, Parsa Region.

Introduction: The sacrum is a large triangular bone, formed by the fusion of five sacral vertebrae. The opening at the caudal end of sacral canal is known as sacral hiatus. It is formed due to the failure of fusion of laminae of the fifth (occasionally fourth) sacral vertebra. Sacrum is one of the bones which exhibit variations and the variation of sacral hiatus is of great clinical significance because it may also leads tomechanical low back pain. Previousworks on themorphometrical study on the sacral hiatus is limited, especially in Nepal, Parsa population. The present study was undertaken to help in filling this gap at least to a certain extent and also made an attempt to find out the variations of sacrum. Materials: One hundred dry human sacra were collected from the Department of Anatomy of National medical college & Teaching Hospital, Nepal. Methods& Observations: Themorphometrical studieswere done, and the parameters (Shape, length, Transverse width & Antero-posterior width of sacral hiatus and level of apex & base of sacral hiatus) were measured with the help of divider, the observations were recorded, tabulated & analyzed. Result: The study showed a significant co-relation between anatomical variations of sacral hiatus with the previous studies.

Bilateral Supernumerary Heads of Biceps Brachii.

The Biceps brachii is a muscle of flexor compartment of the arm. The biceps brachii muscle shows variation in the number of heads, with an estimated 9–22% of all people having a supernumerary head. Themost common variation is third head, but four, five, or even seven heads have been reported. Although supernumerary heads of the biceps brachii muscle have been frequently reported, bilateral asymmetric occurrence of supernumerary heads is relatively rare. During a routine cadaveric dissection at the Department of Anatomy, National Medical College, Birgunj, Nepal, we encountered bilateral supernumerary heads of the biceps brachii muscle; Three heads on the right arm and four heads on the left arm in a 68 year old male cadaver. These additional heads were supplied by branches from the musculocutaneous nerve. No additional anomalies were found on the remainder of both upper limbs of the same cadaver. It may cause compression of surrounding neurovascular structures or itmay lead to variation of normalmechanical actions and also can cause erroneous interpretation during routine surgeries.