Answer:
1- common origin for muscles that move the arm
scapula (except latissimus dorsi and pectoralis major)
2- common insertion for muscles that move the arm
humerus (except latissimus dorsi and pectoralis major)
3- common innervation of muscles that move the arm
cervical nerves
4- coracobrachialis
origin: scapula
insertion: humerus
innervation: cervical nerve
action: adduction and flexion of shoulder
5- deltoid
origin: scapula
insertion: humerus
innervation: cervical nerve
action: abduction of shoulder
-anterior- flexion and medial rotation of shoulder
-posterior- extension and lateral rotation of shoulder
6- supraspinatus muscle
origin: scapula
insertion: humerus
innervation: cervical nerve
action: abduction at shoulder
7- infraspinatus muscle
origin: scapula
insertion: humerus
innervation: cervical nerve
action: lateral rotation of shoulder
8- subscapularis
origin: scapula
insertion: humerus
innervation: cervical nerve
action: medial rotation of the shoulder
9- teres major and minor
origin: scapula
insertion: humerus
innervation: cervical nerve
actions
-major: extension and medial rotation of shoulder
-minor: lateral rotation and adduction of shoulder
10- triceps brachii (long head)
origin: scapula
insertion: humerus
innervation: cervical nerve
action: extension at the elbow
11- latissimus dorsi
origin: spinous process T7-T12
insertion: intertubercular groove of humerus
innervation: cervical nerve
action: abduction and medial rotation of shoulder
12- pectoralis major
origin: clavicle and sternum
insertion: intertubercular groove of humerus
innervation: cervical nerve
action: flexion, extension, adduction, medially rotate arm at shoulder
13- origin of latissimus dorsi
spinous process C7-C12
14- insertion of latissimus dorsi
intertubercular groove of humerus
15- action of latissimus dorsi
abduction and medially rotate shoulder
16- origin of pectoralis major
clavicle and sternum
17- insertion of pectoralis major
intertubercular groove
18- action of pectoralis major
flexion, extension, medial rotation, adduction of shoulder
