A typical muscle variation of latissimus dorsi - the axillary arch is represented by the muscular or fibromuscular slip detached from the anteroinferior border of the musculus latissimus dorsi passing over the axilla under the axillary fascia crossing the medial side of the brachial plexus to continue as a septum intermusculare mediale brachii distally to the medial epicondyle of hume... https://www.roneverhart.com/Traditional-Karate-Do-Okinawa-Goju-Ryu-Book-1-The-Fundamental-Techniques-by-Morio-Higaonna-Preowned/