Your latissimus dorsi (your "lats") is a broad, flat, triangle-shaped muscle that spans your middle and lower back and extends to the front of your humerus (upper arm bone). It plays a role in many ...

Armpit pain is a common complaint that can have many causes, from mild muscle injuries to swollen lymph nodes and severe skin infections. In most cases, armpit pain isn't a reason to worry, but it can ...