Unilateral existence of Chondro-epitrochlearis: Its embryological perspectives and clinical implications

Chondroepitrochlearis (CET) is an anomalous muscular slip that originates from the pectoralis major muscle and inserting into epicondyle of the humerus. The morphology of this variant form of pectoralis major can vary from slender to strong musculo-tendinous. In its course, it usually crosses the neurovascular structures of arm; their compression is a major complication that could be manifested by its persistence. In the present case, potentially anomalous CET muscle with the slender slip of origin, but strong tendinous insertion to the medial epicondyle of the humerus was found unilaterally. This musculo-tendinous structure was found to be compressing the brachial artery and median nerve in the arm. Detailed embryological and clinical perspective of such variant muscular slip helps the physiotherapists, orthopaedicians in their treatment strategy in complain of restricted shoulder movement. It may also help the neurologists, radiologists in their diagnostic approach of ulnar neuropathy.