Medically reviewed by Stuart Hershman, MDFact checked by Maddy SimpsonThe shoulder joint is the articulation between the thorax and the arm. This joint is one of the most complex and mobile joints of ...

Deltoid Abduction of the shoulder (moving the arm outwards and away from the body) Outward arm action in a jumping jack Rotator cuffs A group of stabilising muscles of the shoulder which helps to ...