The Axillary Arch Inserted to the Coracoid Process Compressing the Brachial Plexus

The axillary arch is a variant slip extending between the latissimus dorsi muscle and the pectoralis major.During educational dissection, a variant muscle was found in left arm of 70-year-old female cadaver.A slip muscle originated from the lateral margin of the latissimus dorsi and crossed the axilla obliquely.Therefore, we defined this muscular variation as axillary arch.It ran anterior (superficial) to the medial and lateral cords of the brachial plexus, and then it inserted to coracoid process.We reported this variant muscle and discussed its clinical significances.