The document reviews the major muscles of the shoulder and their actions, providing examples of exercises to target specific muscles. It also discusses common shoulder injuries like impingement syndrome, rotator cuff tears, shoulder dislocations, and labral tears, explaining the causes and symptoms of each condition. Practice questions are included to test knowledge of shoulder muscle identification and their movements.

1. A Review of the Shoulder
Muscles and Their Actions

2. Questions
• What muscle works closely with the anterior deltoid?
• Pectoralis major
• What muscle is involved in any lifting movements?
• Deltoid
• What is the major (strongest) extensor muscle?
• Latissimus Dorsi
• Name the four rotator cuff muscles.
• Subscapularis, Supraspinatus, Infraspinatus, and Teres
minor.
• What muscle works closely with the infraspinatus?
• Teres minor

3. Practice
• Name the muscles • Name the muscles
for Horizontal for Horizontal
Adduction Abduction
• Pect Major (both) • Deltoid (post)
• Corachobrachialis • Infraspinatus
• Deltoid (anterior) • Teres minor
• Lats

4. Practice
• List the muscles that • List the muscles that
do flexion of the do extension of the
shoulder shoulder
• Coracobrachialis • Latissimus dorsi
• Pectoralis major • Teres major
(upper to 60°) • Posterior deltoid
• Anterior Deltoid • Pectoralis major
(lower fibers to
neutral)

5. Practice
• List the muscles that List the muscles that do
do adduction of the abduction of the
shoulder shoulder
• Pectoralis major • Deltoid (all sections)
(lower and upper • Supraspinatus
below 90°) • Pectoralis major
• Coracobrachialis (upper past 90°)
• Latissimus dorsi
• Teres major

6. Practice
• List the muscles that • List the muscles that
do internal rotation do external rotation
of the shoulder of the shoulder
• Subscapularis • Infraspinatus
• Latissimus dorsi • Teres minor
• Teres major • Posterior deltoid
• Anterior deltoid
• Pect. major

7. Name the muscle.
Coracobrachialis
Name the action
Adduction of
the shoulder
Also, flexion
and hor. add.

8. Name the muscle.
Pectoralis Major

9. Name the muscle.
Subscapularis
Name the action
Internal
rotation of the
shoulder

10. Name the muscle.
Deltoid
Name the action
Abduction of
shoulder

11. Name the muscle.
Infraspinatus
Name the action
External
rotation

12. Name the muscle. Name the action
Teres Major Adduction of
scapula

13. Name the muscle.
Teres Minor
Name the action if the humerus move directly to the posterior
Extension of the shoulder

14. Name the muscle.
Supraspinatus
Name the action
Abduction of the shoulder

15. Coracobrachialis Pect. Major
Subscapularis
Deltoid

16. Supraspinatus Teres Major
Infraspinatus
Teres Minor

17. What position are her shoulders in?
Flexion

18. What position is his right shoulder in?
Horizontal Abduction and
External Rotation

19. What rotation action is his shoulder performing as he
continues to through the ball?
Internal Rotation

20. What position are her shoulders in?
Flexion

21. What position are his shoulders in?
Horizontal abduction or Extension

22. Position of their shoulders? 2.
1.
Extension
Flexion

23. What is the position of shoulders?
Extension

24. Shoulder Muscle Exercises

25. Major Muscles of the Shoulder
• Pectoralis major • Latissimus dorsi
– Push-ups – Chinning
– Pull-ups – Robe climb
– Bench press – Dips on parallel bars
– Throwing – Pullover exercises
– Tennis serve – Pulldown exercises
– Rowing

26. Shoulder action = ? Deltoid
Abduction
Shoulder muscle(s) = ? Supraspinatus

27. Shoulder action = ?
Shoulder muscle(s) = ?
Flexion
Ant Deltoid
Upper Pect Major
Coracobrach.

28. Shoulder action = ? Ant. Deltoid
Shoulder muscle(s) = ? Horizontal Add. Pect. Major (both)
Coracobrachialis

29. Shoulder action = ?
Horizontal Abduction
Shoulder muscle(s) = ?
Latissimus Dorsi
Post. Deltoid
Teres Minor
Infraspinatus

30. Shoulder action = ?
Shoulder muscle(s) = ?
Adduction
Pect. Major (both)
Coracobrachialis
Latissimus Dorsi
Teres Major

31. Shoulder action = ? Horizontal Add
Shoulder muscle(s) = ?
Ant. Deltoid
Pect. Major (both)
Coracobrachialis

32. Shoulder action = ?
Shoulder muscle(s) = ?
Extension Lats Teres Major
Post. Deltoid Pectoralis Major (lower)
Infraspinatus Teres minor

33. Shoulder action = ? External Rotation
Shoulder muscle(s) = ? Infrspinatus
Teres Minor
Post. Deltoid

34. Name a shoulder muscle isolated
with the following exercises.
• Side arm dumbbell raises
• Deltoid
• Push-ups
• Pectoralis major
• Rowing and pull-overs
• Latissimus dorsi

35. What is the action to the left? What
muscles perform that action?
External Rotation
Internal Rotation
Internal Rotation
Subscapularis, Ant. Deltoid, Pect, Major, Lats. And Teres Major

36. Rotator Cuff Exercises
External Rotation
Internal Rotation
External Rotation
Abduction (to work the supraspinatus)

37. Shoulder Related Injuries
• The shoulder is built
for motion, not stability
• Injury rate depends
on…
– Shallowness of glenoid
fossa
– Laxity of ligaments
– Strength of muscles

38. • Shoulder subluxation
– Incomplete or partial dislocation
• Shoulder dislocation
– Complete dislocation of the GH joint
– Most common anteriorly and inferiorly
• Shoulder separation
– Complete dislocation of the AC joint

39. Shoulder Dislocation

40. Impingement Syndrome

41. Impingement Syndrome
• A condition that decreases
the subacromial space
– Acromion process
– Coracoacromial ligament
• Causes
– Swelling
– Bone spurs
– Anatomical structure

42. Impingement Syndrome

43. Rotator Cuff Tears

44. Rotator cuff
• Subscapularis
• Supraspinatus
• Infraspinatus
• Teres minor

45. Movement of RC Muscles
• Subscapularis is an
internal rotator of the arm.
• Supraspinatus assists the
deltoid in abducting the
arm, with its greatest
contribution being the
initiation of abduction.
• Infraspinatus and teres
minor muscles both
externally rotate the arm.

46. Rotator Cuff Injury
• The throwing motion has been divided
into five phases: wind-up, cocking,
acceleration, and follow-through.
• Cocking phase
– Subscapularis fires in late cocking phase
to decelerate the shoulder's external
rotation. Also, it is stretched during the
cocking phase.

47. Rotator Cuff Injury
• Follow-through (muscles fire most
intensely)
– Subscapularis internally rotates the shoulder,
– The infraspinatus and teres minor contract
eccentrically to decelerate the arm and are
stretched.
• During this repetitive eccentric loading, the
rotator cuff is prone to overload, fatigue,
tendinitis, and even a partial undersurface
tear.

49. Note: Surgery needs
to be performed
within 3 months or
the supraspinatus
muscle will atrophy
and be too short to
reattach

50. Glenoid Labrum

51. Labral Tear
• The glenoid cavity makes up the “socket” of the shoulder
joint.
• The labrum acts sort of like a gasket, turning the flat
surface of the glenoid into a deeper socket that molds to
the head of the humerus for a better fit.
• A tear of labrum can cause pain and a catching
sensation with movement of the shoulder.

52. Labral Tear
• Most labral tears are probably the result of an injury to the
shoulder, such as falling on an outstretched hand.
• There is reason to believe that the excess motion of the
humerus moving around on the glenoid may cause
damage to the labrum over time.
• An unstable shoulder may also cause injury to the labrum,
if it repeatedly dislocates out of the glenoid.