muscles acting on the shoulder

pectoralis minor

• protraction of shoulder, as in reaching out for a door handle

• rotation of scapula and depression of apex of shoulder, as in reaching down to pick up a suitcase

serratus anterior

• rotation of scapula as in lifting a suitcase or raising arm above head

• fixation of scapula when carrying weights in front of body

• protraction of scapula

• prime mover of all forward-reaching and pushing actions

• holds scapulae against rib cage

• “boxer’s muscle”

traspezius

• lateral rotation of scapula, elevating apex of shoulder as in picking up a suitcase

• elevation of scapula as in shrugging shoulders

• retraction of scapula as in pulling on a rope

• fast, forcible depression of scapula as in hammering and swimming

• fixation of scapula and shoulder during other arm movements

levator scapulae

• elevation of scapula

• medial rotation of scapula, depressing apex of shoulder

• retraction of scapula and bracing of shoulder

• lateral flexion of neck

rhomboid minor & major

• retraction of scapula and bracing of shoulder

• fixation of scapula during other arm movements