Your armpit, also known as the axilla, contains a large collection of lymph nodes, hair follicles, and sweat glands. A number of things can cause pain in the hollow created by your chest wall, muscles ...

Medically reviewed by Theresa Marko, PT, DPT, MS Key Takeaways Armpit pain can come from injuries, infections, or swollen lymph nodes.  To diagnose armpit pain, doctors may use lab tests, physical ...