03-04: The Shoulder Girdle

Question 1

Shoulder Complex

Answer 1

Scapula, Clavicle, Sternum, Humerus, Rib Cage, Sternoclavicular Joint, Acromioclavicular Joint, Glenohumeral Joint, Scapulothoracic articulation

Question 2

Shoulder Girdle

Answer 2

Scapula, Clavicle, Sternum

Question 3

Motions of Shoulder Girdle

Answer 3

Elevation and Depression, Protraction (ABD) and Retraction (ADD), Upward and Downward Rotation, Anterior Tilt (Sagittal Plane Adjustment), Internal and External Rotation (Horizontal Plane Adjustment)

Question 4

Upward and downward rotation

Answer 4

Upward rotation - Inferior angle away from spine

Downward rotation - Inferior angle towards spine

Question 5

Anterior tilt (sagittal plane adjustment)

Answer 5

Inferior angle moves away from thoracic wall

Question 6

Internal and external rotation - “winging”

Answer 6

Vertebral border moves away from thoracic wall

Question 7

Resting position of scapula

Answer 7

Superior angle - T2
Spine of the scapula - T3
Inferior Angle - T7-T8

Between T2 and T7/T8, 2”-3” lateral from spinous processes of the verterbrae, Spine of the scapula is level with spinous process of T3/T4

Question 8

Three major ligaments of sternoclavicular joint

Answer 8

Sternoclavicular ligament, Interclavicular Ligament, Costoclavicular Ligament, Articular disk (inside SC ligament)

Question 9

Sternoclavicular ligament

Answer 9

• Connects clavicle to sternum

- Provides reinforcement to the joint capsule

Question 10

Interclavicular ligament

Answer 10

• Top of the manubrium, connecting superior sternal ends of the clavicles
• Limits the amount of clavicular depression

Question 11

Costoclavicular ligament

Answer 11

• Connects the inferior surface of the clavicle to the superior surface of the costal cartilage of the 1st rib; Short, flat, rhomboid-shaped
• Limits the amount of clavicular elevation

Question 12

Coracoclavicular ligament

Answer 12

• Not directly on joint, but provided stability to joint
• Limits elevation of scapula laterally
• Trapezium - lateral, Conoid - medial

Question 13

Coracoacromial ligament

Answer 13

• Does not cross joint, but forms arch over the head of the humerus; Protects subacromion elements
• Starts and ends on scapula (coracoid to acromion)

Question 14

Acromioclavicular joint

Answer 14

• Connects scapula to axial skeleton; Triaxial joint

- Two ligaments: acromioclavicular ligament, Coracoacromial ligament

Question 15

Separated shoulder

Answer 15

Injury where coracoclavicular ligament tears upon force

Question 16

Scapulothoracic joint (ST)

Answer 16

• Not a true joint
• Wide ROM of shoulder complex
• ST Motion = AC Motion + SC Motion (creates scapular movement

Question 17

Sternoclavicular joint

Answer 17

• Convex and Concave ends

- Glide changes dependent on which way the scapula moves

Question 18

Primary movements of scapulothoracic joint (ST)

Answer 18

Elevation and Depression, Retraction and Protraction, Downward and Upward Rotation

Question 19

ST Elevation

Answer 19

• SC joint elevation + downward rotation at AC joint
• Convex on Concave at SC joint
• Occurs in frontal plane, sagittal axis @ SC joint

Question 20

ST Upward Rotation

Answer 20

• SC joint elevation + upward rotation at AC joint

Question 21

ST Protraction and Retraction

Answer 21

• Rotation around vertical axis @ SC joint
• Occurs in horizontal plane
• Concave (clavicle) on Convex (sternum)
• Anterior Glide (Protraction), Posterior Glide (Retraction)

Question 22

ST Anterior Tilt

Answer 22

• Posterior Rotation of Clavicle
• Posterior Glide
• Occurs in sagittal plane, frontal axis @ SC joint

Question 23

Three planes of motion for AC joint

Answer 23

IR/ER - Horizontal Plane Adjustment “winging” - vertical axis
Upward/Downward Rotation - Sagittal axis
Anterior Tipping - Sagittal Plane Adjustment - Frontal Axis

Question 24

AC & CL movements

Answer 24

• Both convex ends = unstable

- Cartilagenous disk between ends provides stability (convex on concave)

Question 25

Muscles of the Shoulder Girdle

Answer 25

Trapezius (3), Levator Scapula, Rhomboids (2), Serratus Anterior, Pectoralis Minor

Question 26

Upper Trapezius

Answer 26

O: Occiput, Nuchal Ligament, SPs of C1-C6 I: Lateral 1/3 of clavicle, acromion (anterior aspect) A: Scapular elevation (prime mover), upward rotation, assist with retraction N: Cranial Nerve XI (Accessory) - Upward Line of Pull

Question 27

Middle Trapezius

Answer 27

O: SPs of C7-T3 I: Spine of Scapula A: Scapular retraction (prime mover), upward rotation N: Cranial Nerve XI (Accessory) - Middle Line of Pull

Question 28

Lower Trapezius

Answer 28

O: SPs of T4-T12 I: Base of spine of scapula A: Scapular depression (prime mover), upward rotation, assist with retraction P: Cranial Nerve XI (Accessory) - Downward (Vertical) Line of Pull

Question 29

Rotational Movement of Scapula (Upward/Downward)

Answer 29

Force Couple - Lower and Upper trap work opposite directions of each other; assisted by serratus anterior

Question 30

Levator Scapula

Answer 30

O: TPs of C1-C4 I: Superior angle of scapula down to spine of scapula A: Assist with scapular elevation, downward rotation N: Dorsal Scapular (C5 Root) - Ribbon shaped; very thin, so susceptible to injury; deep to trapezius

Question 31

Rhomboids

Answer 31

O: Minor - SPs of C7-T1, Major - SPs of T2-T5 I: Vertebral border of scapula from base of spine to inferior angle (Minor - Base of Spine, Major - Bottom of Base) A: Retraction (with downward rotation component, lifts scapula slightly - elevation) N: Dorsal Scapular (C5 Root)

Question 32

Serratus Anterior

Answer 32

O: Lateral aspect of ribs 1-8 I: Anterior aspect of vertebral border of scapula A: Scapular protraction (prime mover), upward rotation N: Long Thoracic (C5, C6, C7 Roots) - Reaches under costals to reach vertebral border - Deepest muscle of shoulder girdle - Holds scapula against thoracic wall - If weak or gone, scapula will "wing"

Question 33

Pectoralis Minor

Answer 33

O: Anterior aspect of ribs 3-4 I: Coracoid process of scapula A: Scapular depression, Anterior tilt (sagittal plane adjustment), downward rotation N: Medial pectoral - Deep to pectoralis major - Neurovascular bundle runs under pec major (compress and symptoms over upper extremities = TOS)

Question 34

Reverse Action - Upper Trapezius

Answer 34

Extends head and neck, ipsilateral lateral head bend, contralateral head rotation

Question 35

Reverse Action - Lower Trapezius

Answer 35

Assist in elevating trunk

Question 36

Reverse Scapula - Levator Scapula

Answer 36

Rotate and laterally bend neck