The pectoralis quartus and chondro-epitrochlearis combined muscle variation: description and surgical relevance

The authors describe a rare unilateral muscle variation in the thoracic wall combining the and muscles. A routine dissection was performed in the upper right limb of a male adult cadaver with approximately 35-50 years of age, embalmed in formalin 10%. An accessory muscle, the was identified and was associated with a tendon that was inserted in the medial humeral epicondyle, characteristic of the muscle tendon. Such variations have significant clinical relevance to orthopedics, mastology, neural and vascular surgery, and other specialties, for surgical approaches in both the axillary and brachial regions.