Nerve Entrapment In The Osseoaponeurotic Tunnel Mimicking Struther’s Ligament Associated With Superficial Brachial Artery: An Embryological Error

ABSTRACT

Introduction: Coracobrachialis muscle is well known for its morphological variations. Anatomical variation ofcoracobrachialis near its insertion can cause compression of median nerve and brachial artery by mimickingstruther’s ligament. Our aim of the study was to examine and record the variations in origin and insertion ofcoracobrachialis muscle and to see their relationship with the median nerve and brachial artery.Methodology: During routine dissection for undergraduate students in KFMSR, 64 upper limbs were dissectedand observed for any variations in origin and insertion of Coracobrachialis muscle.Results: Of the 64 upper limbs dissected, we noted that in one cadaver, there were two heads of origin forcoracobrachialis muscle and there was also a variation in the insertion as abnormal slips, which were attachedto antebrachial fascia. The blood supply to this muscle was from the muscular branches of superficial brachialartery.Conclusion: The knowledge of this type of variations is important for surgeons, radiologists, neurologists andphysiotherapists for proper decision making during surgical considerations and injuries around elbow joint.Neurovascular structures like median nerve and superficial brachial artery may be compressed by the abnormalslips of coracobrachialis close to insertion.