Unusual fibrous band in the brachium - a probable remnant from the rare chondroepitrochlearis muscle

Abstract

An unusual fibrous band in the medial brachial region was found during routine anatomical dissection of the left upper limb of a 67-y-old female cadaver. This interesting structure started from the posterior layer of the pectoral major fascia. The fibrous band emerged from the lower border of the pectoralis major close to its humeral attachment, it then crossed obliquely downwards and posteriorly the medial brachial region and finally it was attached to the medial epicondyle of the humerus. Most probably, this fibrous structure represents a remnant from the chondroepitrochlearis - a variant muscle that is rarely observed in man. Because this fibrous band has very close relations to the brachial vessels and the median and ulnar nerves in the arm, in certain circumstances it may probably cause neurovascular compression.