1. What is the Shoulder girdle?

2. What is the importance of Shoulder Girdle
Increase the ROM for Upper limb (up to 180°)
Provide More space to reach for upper limb
Provide an stable base for upper limb function

3. What are the Joints of the Shoulder girdle?
Four interdependent linkages for Shoulder Complex
Functional Articulation: Scapulothorasic Joint (STJ)
Anatomical Articulation: Sternoclavicular Joint (SCJ)
Anatomical Articulation: Acromioclavicular Joint (ACJ
Anatomical Articulation: Glenohumeral Joint (GHJ)

4. Sternoclavicular Joint

5. What is the role of Sternoclavicular Joint within shoulder girdle?
Functional base for scapula
Movement in Clavicle and SCJ
Movement in Scapula Thoracic

6. Sternoclavicular Joint
Can You Describe the Sternoclavicular Joint?
Sternoclavicular Joint
Consists of two saddle-shaped surfaces but
A plane Synovial Joint
3 degree of freedom
Joint Capsule
3 Major Ligaments
A Joint Disc
4 joint’s area contact
Clavicle
Movement in SCJ is due to the change in contact area between
Sternocalvicular
Disc
Manuberium

7. Can you describe the function of Sternoclavicular Disc Joint?
A fibrocartilage joint disk, or meniscus, that increases congruence between joint surfaces
Acts like a hinge or pivot point during clavicle motion.
Act like axis in the SCJ
In Elevation/Depression
Clavicle move against Manuberium and Disc
Upper part of Disc act like axis)
In Protraction/Retraction
Disc and Clavicle Move against Manuberium
Lower part of Disc act like axis

8. the mechanical axis for these two movements located not at the SC joint itself but at the more laterally located costoclavicular ligament

9. How the disc Joint does provide stability for SCJ?
Disc has an Important Role in Joint Stability
By Creation congruent between Joint surface
By absorption coming stresses to the lateral end of clavicle

10. Three-Compartment SC Joint
Anatomic examination of the SC articulation has led to the proposal that there are three functional units
a lateral compartment between the disk and clavicle for elevation and depression;
a medial compartment between the disk and manubrium for protraction and retraction;
a costoclavicular joint for anterior and posterior long axis rotation.

11. Sternoclavicular Joint Capsule and Ligaments
The SC joint is surrounded by a fairly strong fibrous capsule but must depend on three ligaments for the majority of its support. These are the sternoclavicular ligaments,

12. Can you name the Sternoclavicular Ligaments?
Sternoclavicular Lig (Ant & Post)
Costoclavicular Lig (Ant & Post)
Inter Clavicular Lig

13. What is the function of Sternoclavicular Ligaments?
Sternoclavicular (Ant & Post) Lig
Strengthening of Ant and Post part of Joint
Prevent of Ant and Post Movements of Clavicle
Costoclavicular (Ant & Post parts) Lig
Very strong Lig
Both parts resist against the 1) superior force from SCM and 2) against elevation of the lateral end of clavicle
At the limit reach, they are responsible for inferior gliding of clavicle
Post part prevent of inward movement of clavicle (absorb of forces acts on the Disc from arm)
Inter Clavicular Lig
Control 1) Depression of clavicle, 2) superior gliding of clavicle and protect subclavian artery and Brachial plexus and
Weight bearing of upper arm by help of upper capsule

14. Three Major functions for SCJ
Integrity of These elements
Clavicle
SCJ Disc
Manuberium
Ligaments
Capsule
PROVIDS
Three Major functions for SCJ
Resist against Applied stress from Upper arm
Provide Mobility for Upper arm
Provide a Strength Base for Upper arm

15. What are the Sternoclavicular Movements?
Motions of any joint are typically described by identifying the direction of movement of the portion of the lever that is farthest from the joint.
Elevation/Depression
Protraction/Retraction
Anterior/Posterior Rotation

16. Can you describe Elevation/Depression movements?
Occur around the Ant-Post Axis which located in Costoclavicula Lig
In the plan that convex surface of clavicle glide against concave surface of manubrium and Disk
Opposite Movement of medial part of clavicle
Up to 48 degree Elevation and 15 degree Depression
Elevation of clavicle accompanied by elevation of scapula and its upward rotation
Small magnitudes of medial-lateral translation and superior/inferior translation in the medial aspect of clavicle

17. Elevation and Depression

18. Can you describe the Protraction/Retraction movements?
Occur vertical axis locate in costoclavicula Lig
In the plan that concave surface of clavicle glide against convex surface of manubrium
In protraction, lateral end rotate anteriorly, and medial end slide anteriorly
degree Protraction and degree Retraction
Pro/Ret of clavicle is accompanied by Pro/Ret of scapula

19. Protraction and Retraction

20. Can you describe the Anterior/Posterior Rotation?
Occur around the longitudinal axis of clavicle intersecting AC and SC Joint
An Spin movement saddle surface of medial part of clavicle and manuberium/first costal cartilage
Movement start from neutral position only toward posterior rotation
35-55 ° Post Rot and 10 ° available Ant Rot
It serve the last 30 degree of upward rotation of scapula.

21. Posterior And Anterior Rotation

22. ■ Sternoclavicular Stress Tolerance
The Complex of bony segments, Capsuloligamentous structure, and the SC disk produce a joint with dual functions of mobility and stability.
The SC joint contribute to upper limb mobility, and withstanding imposed stresses.
Although the SC joint is considered incongruent, the joint does not undergo the degree of degenerative change common to the other joints of the shoulder complex.
Dislocations of the SC joint represent only 1% of joint dislocations in the body.

23. Acromioclavicular Joint

24. Acromioclavicular Joints
Characteristics
Plan Synovial Joint
3 rotational and 3 transitional degrees of Freedom
Weak capsular joint
Joint Disc
Two Major Ligaments
Superior & Inferior Acromioclavicular ligaments
Integration of joint surface
Provide horizontal stability
Coracoclavicular Lig.
Its primary function included:

25. Primary function of ACJ
Allow the scapula additional range of rotation on the thorax
Allow for adjustments of the scapula (tipping and internal/external rotation) in order to follow the changing shape of the thorax as arm movement occurs.
Allows transmission of forces from the upper extremity to the clavicle.

26. Articular Surface and Joint Disc of ACJ
The articular facets, considered to be incongruent, vary in configuration
Intra-articular movements for this joint are not predictable.
A Joint disk with variable in size between individuals exist in AC joint
It plays as a “meniscoid” fibrocartilage remnant within the joint to develop each articulating surface during upper extremitymovement

27. The Acromioclavicular Joint

28. Acromioclavicular Capsule and Ligaments
Capsule is weak and cannot maintain integrity of the joint without reinforcement by ligaments
The superior acromioclavicular Lig are reinforced by aponeurotic fibers of the trapezius and deltoid muscles and assists capsule by
Apposing articular surfaces
Controlling A-P joint stability. The fibers of the superior AC ligament are
the superior joint support stronger than the inferior

30. Acromioclavicular Capsule and Ligaments
Coracoclavicular Ligaments which divided into:
Lateral portion, the trapezoid ligament,
provides the primary restraint for the AC joint in the superior and inferior directions
Medial portion, the conoid ligament.
Provides the majority of resistance to posterior translatory forces applied to the distal clavicle.
They are separated by adipose tissue and a large bursa
Both portions of the coracoclavicular ligament limit upward rotation of the scapula at the AC joint
Transfer Medially directed forces on humerus to the SCJ
Transfer the rotational force of scapula to the clavicle and then cause Posterior Rotation at SCJ

31. When a person bears weight on the arm, a medially directed force up the humerus (1) is transferred to the scapula (2) through the glenoid fossa and then to the clavicle (3) through the coracoclavicular ligament

32. Acromioclavicular Motions
The primary rotatory motions of AC joint are
Internal/external rotation,
Anterior/ posterior tipping or tilting,
Upward/downward rotation
These motions occur around axes that are oriented to the plane of the scapula rather than to the cardinal planes.
Small translatory motions of AC joint included:
Anterior/Posterior,
Medial/Lateral,
Superior/Inferior.

33. Plane of AC joint Movements

34. What movement does occur in the Acromioclavicular joint?
1- Internal and External Rotation

35. Internal and External Rotation
Occurs around an approximately vertical axis through the AC joint
To Maintain contact of the scapula to horizontal curvature of the thorax during Protraction and Retraction
To orient the glenoid fossa toward the plan of humeral elevation
30 degree the total ROM
An Anterior/Posterior translatory movement

36. Internal and External Rotation at AC joint
Glenoid Fossa is the reference for naming the movement
Because of the thorax curvature, Internal/External Rotation is a necessary movement for protraction and Retraction

37. Anterior and Posterior Tipping
Occurs around an oblique “coronal” axis of joint
Ant. tipping will result in the acromion tipping forward and the inferior angle tipping backward during downward rotation and also Elevation of scapula
Posterior tipping will rotate the acromion backward and the inferior angle forward. during upward rotation and also Depression of scapula
To Maintain contact of the scapula with the contour of the rib cage and orient the glenoid fossa during arm flexion and abduction
30-40 degree the total ROM
A Superior/posterior translatory movement

38. Anterior and Posterior Tipping
The superior aspect of scapula is the reference of naming the movement
The acromion has slightly translatory anteriorly/posteriorly movement

39. Upward and Down Ward Rotation at AC Joint
Around an A-P axis (perpendicular to scapula)
Direction of Glenoid Fossa is the reference for the naming the movement
Acromion has a small medial/lateral Translatory movement

40. 3-Scapula Upward and Downward Rotation
Help to orient the glenoid fossa upward or downward
Coraco-Clavicular Ligament limit this movement
Posterior rotation of clavicle lax the lig
So upward rotation can be done in the AC Joint
30 degree Upward Rot
17 degree Downward Rot

41. Acromioclavicular Stress Tolerance
AC joint is extremely susceptible to both trauma and degenerative change due to the
its small and incongruent surfaces
Degenerative change is common from the second decade with narrowed joint space by the sixth decade.
Treatment of sprains, subluxations, and dislocations of this joint occupies a large amount of the literature on the shoulder complex

42. Acromioclavicular Stress Tolerance
Various classification of injury commonly
Type I injuries consist of a sprain to the AC ligaments,
Type II injuries typically have ruptured AC ligaments and sprained coracoclavicular ligaments
Type III injuries result in rupture of both sets of ligaments,
Types I, II, and III AC separations all involve inferior displacement of the acromion in relation to the clavicle caused by the loss of support from the coracoclavicular ligaments

43. Acromioclavicular Stress Tolerance
Various classification of injury commonly
Type IV injuries have a posteriorly displaced lateral clavicle, often pressing into the trapezius posteriorly, with complete rupture of both the AC and coracoclavicular ligaments
Type V injuries also involve an inferior displacement of the acromion and complete rupture of both sets of ligaments and are distinguished from type III by a severity of between three and five times greater coracoclavicular space than normal.
Type VI injuries have an inferiorly displaced clavicle in relation to the acromion, with complete ligament rupture and displacement of the distal clavicle into a subacromial or subcoracoid position.

44. Scapulothorasic Joint

45. Rotation at AC Joint
SCJ Elev/Dep and ACJ Rotation are necessary movements for Scapula Elevation and Depression

46. ACJ Rotation and SCJ Elev and Post Rotation are the necessary movements for Scapular upward Rot

47. Resting Position of scapula
Position of Scapula on the Thorax
2 inches from the midline
Between 2nd and 7th ribs
30-45 degree internally rotated from the coronal plane
10-20 degree anteriorly tipping from vertical
10-20 degree upward rotation, it is different among the individuals

49. What is the Movement of Scapula?
Elevation/Depression
Protraction/Retraction
Upward Rotation/Downward Rotation

50. Scapula Upward and downward Rotation
Upward rotation of the scapula plays a significant role in increasing the range of elevation of the arm
Approximately 60º of upward rotation is available.
Considering the closed-chain relationship between the SC, AC, and ST joints, they contribute to scapula upward/downward rotation by:
SC joint elevation/depression,
SC joint posterior/anterior rotation
AC joint upward/downward rotation
Most often, scapular upward/downward rotation results from a combination of the SC and AC motions.

51. Scapula Upward and downward Rotation

52. Scapula Elevation/Depression
Scapular elevation and depression can be isolated by shrugging the shoulder up and depressing the shoulder downward.
It is described as translatory motions
Scapular elevation, occurs by elevation of the clavicle at the SC joint and requires Scapula adjustments in
anterior/posterior tipping
internal/external rotation at the AC joint
to maintain the scapula in contact with the thorax

53. Scapula Elevation/Depression

54. Scapula Protraction/Retraction
Scapula Protraction and retraction are described as translatory motions of the scapula away from or toward the vertebral column, respectively.
However, if protraction occurred as a pure translatory movement, only the vertebral border of the scapula would remain in contact with the rib cage.
In reality during protraction, scapula follows the contour of the ribs by
rotating internally and externally at the AC joint and
clavicular protraction and retraction at the SC joint
So, glenoid fossa facing anteriorly with the full contact of scapula with the rib cage

55. Scapula Protraction/Retraction

56. Scapula Internal/External rotation
Scapular internal and external rotation are
normally not overtly identifiable on physical observation
but are critical to its movement along the curved rib cage.
The Movement normally accompany protraction/ retraction of the clavicle at the SC joint
Isolated Scapula Int rotation at the AC joint, cause
Prominence of the vertebral border of scapula
Loss of contact of scapula with the thorax.
Which is referred to clinically as scapular “winging”
Excessive Int rotation may be indicative of pathology or poor neuromuscular control of the ST muscles.

57. Pathologic Scapula Internal Rotation

58. Scapula Anterior/Posterior Tipping
Anterior/Posterior tipping is
normally not obvious on clinical observation and
yet is critical to maintaining contact of the scapula against the curvature of the rib cage
Movement occurs at the AC joint
normally will accompany anterior/posterior rotation of the clavicle at the SC joint
Isolated excessively Ant/Post Tipping at the AC joint will result
in prominence of the inferior angle of the scapula
Ant. tipped scapula may occur in pathologic situations (poor neuromuscular control) or in abnormal posture.

59. Pathologic Scapula Anterior Tipping

60. What are the Scapulathorasic Functions?
Final function of this Joint
Adjustment of gelenoid direction
To Increased ROM for upper arm
To Provide an Strong Base to control Rolling and gliding Movements for Humorous Surface

61. Scapulothorasic Stability
Scapula Stability on the thorax is provided by
The structures that maintain integrity of the linked AC and SC joints such as ligaments, capsule and joint disc.
The muscles that attach to both the thorax and scapula maintain contact between these surfaces
These muscles also provide stabilization by pulling or compressing the scapula to the thorax.
The scapula, with its associated muscles and linkages, performs mobility and stability functions so well that it serves as a premier example of dynamic stabilization in the human body