Clinically speaking, the pectoralis minor muscle is the little brother of the pectoralis major muscle. Like all little brothers, the pectoralis minor wants to do everything that big brother does, so it’s no surprise that trigger points in these two muscles have almost identical referred pain patterns.
These pain patterns start in the front of shoulder and can extend down the inside of the arm, elbow, forearm, palm of the hand, and into the pinky, ring, and middle fingers.
Not to be outdone by big brother, a tense pectoralis minor muscle can also entrap nerves in the armpit region that cause pain, numbness, and tingling to travel down the arm and into the hand.
