Shoulder Region

Question 1

The Pectoral Girdle

Answer 1

Clavicle, Scapula and Humerus

An interface, support base and shock absorber

Protection for axilary artery and vein, and brachial plexus

Question 2

The Clavicle

Answer 2

6 Muscle attachements

Strut

Mobile

Weight Transer

Question 3

Clavicular Joints

Answer 3

Firmly attached at each ends

Coracoclavicular Ligament and Costoclavicular Ligament

Question 4

Scapula

Answer 4

1. Provides a surface for muscle attachment (17)
2. Firmly attached to the clavicle

Question 5

The Shoulder Joint Complex

Answer 5

4 joints that work in concert

1. Acromioclavicular
2. Sternoclavicular - only bone to bone joint between upper limb and trunk
3. Glenohumeral
4. Scapulothoracic

Question 6

Sternoclavicular Joint

Answer 6

Attaches clavicle to sternum

Only bony joint

Has an articular disc - when fit between bones isnt a good you have a fibrous disc to help them fit together

Question 7

Acromioclavicular Joint

Answer 7

Attaches clavicle to the acromion

The acromion is a continuation of the scapular spine, and hooks over anteriorly. It articulates with the clavicle (collar bone) to form the acromioclavicular joint.

Helps to suspend upper limb

Question 8

Glenohumeral Joint

Answer 8

Connects the Glenoid Fossa and Humerus

The humeral head is held into the glenoid fossa by a group of muscles called the Musculotendenous Rotator Cuff which includes the subscapularis, supraspinatus, infraspinatus, and teres minor

Muscular cuff allows brain greater control

3 attach dorsal, 1 attaches ventral

Question 9

Scapulothoracic Articulation

Answer 9

Allows gliding of scapula across the back between ribs 2 and 7 on thorax

Can rotate so glenoid fossa is point superiourly or inferiorly

Question 10

Muscles of the shoulder area

Answer 10

Act on the pectoral girdle and the upper limb

• Many are on the dorsal side of the trunk
• Almost all are innervated by branches of ventral primary rami
• They act to position the upper limp and fix the pectoral girlde on the trunk

Question 11

Posterior Axioappendicular Muscles

Answer 11

Trapezius

Levator Scapula

Rhomboids

Lattisimus Dorsi

Question 12

Anterior Axioappendicular Muscles

and Innervation

Answer 12

1. Pectoralis Major
2. Pectoralis Minor
3. Serratus Anterior

The Long Thoracic Nerve is superficial with respect to the serratus muscle

Question 13

If the serratus anterior muscle was paralized, how would it affect the scapula?

Answer 13

The medial border of the scapula moves laterally and posterior creating a condition known as Winged Scapula - usally caused by injury to the Long Thoracic Nerve

Injury to the Trapezius mucle can also cause scapular winging

Question 14

Scapulohumeral Muscles

Answer 14

• Deltoid (anterior and posterior)
• Supraspinatus (posterior)
• Infraspinatus (posterior)
• Teres Minor (posterior)
• Teres Major (posterior)
• Subscapularis (anterior)

Question 15

Surface Anatomy

Answer 15

Question 16

Scapular Anatomosis

Answer 16

Two tubes come together so if one is blocked some of the other vessels could enlarge and serve as a pathway to circulate blood - Collaeral Circulation