Study Of Brachialis Muscle: Additional Slip And Its Clinical Significance

ABSTRACT

Background: Brachialis is a muscle of anterior compartment of arm. It has two heads. Superficial head insertinginto ulnar tuberosity innervated by musculocutaneous nerve, the deep head inserts into coronoid process ofulna and supplied by radial nerve. Neuromuscular compression due to presence of additional slip of brachialisforms the basis of this study.Materials and methods: Study was done in 60 adult human cadaveric upper limbs of both the sides irrespectiveof sex in the Department of Anatomy, Kempegowda institute of medical sciences (KIMS), Bangalore and othermedical colleges nearby. Presence of additional slips of brachialis with important and interesting relations wasfound which were comparable with previous studies. As qualitative method was done, Descriptive statisticswere utilized.Results: Additional slips were present in 21.6%. It was found mainly in the left upper limbs in 69.2% and rest30.7% are present in right side limbs. Among 13 specimens, additional slips originated mainly from theanteromedial aspect in 84.6% and in 15.3% it originated from the anterolateral aspect of main brachialis.Additional slips were innervated mostly by the musculocutaneous nerve in 69.2%, median nerve in 15.3% andradial nerve in 7.6%. No innervation was observed in one specimen.Conclusion: Knowledge of additional slips and its origin and course is very important for identifying the causefor neurovascular symptoms due to compression of neurovascular structures