Clinical Anatomy Of The Shoulder & Arm

Question 1

What is the shoulder joint complex?

Answer 1

Region where the upper limb attaching to the trunk

Question 2

What are the bonds if the shoulder joint complex ?

Answer 2

Humerus, scapula, clavicle, thoracic cage

Question 3

What are the 3 synovial joints of the shoulder joint complex?

Answer 3

• Shoulder girdle (scapula and clavicle)
  
  • 1. sternoclavicular
  • 2. Acromioclavicular

Shoulder joint proper
3. Glenohumeral

-Scapulothoracic

• Subacromial space
  
  • common site of impingement

Question 4

Why is the sternoclavicular joint significant?

Answer 4

Only articulation of upper limb to axial skeleton

Stable joint

Question 5

What ligaments comprise the sternoclavicular joint?

Answer 5

1. Anterior sternoclavicular ligament
2. Interclavicular ligament
3. Costoclavicular ligament

Question 6

What is the acromioclavicular joint reinfirced by?

Answer 6

1. Acromioclavicular ligament: strengthens AC capsule superiorly
2. Coracoclavicular ligament: anchors the clavicle to the coracoid process

Question 7

What is the clinical correlate of a fractured clavicle?

Answer 7

Midshaft fracture of clavicle-

Shoulder depressed with arm medially rotated and adducted

Associated intra thoracic injuries:

• Pneumothorax
• Damage to Subclavian vein and artery

Question 8

What anatomy, contributes to a fractured clavicle?

Answer 8

SCM pulls medial fragment of clavicle upwards

Pectoralis major pulls lateral fragment medically

Latissimus dorsi and gravity pulls lateral fragment downwards

Question 9

Describe shoulder separation

Answer 9

• Varying degrees of severity
• tearing of the acromioclavicular joint and ligament with or without the coracoclavicular ligament
• Restricted range of shoulder movement

Question 10

Describe the glenohumoral capsule of the glenohumoral joint

Answer 10

Attaches to the anatomical neck of humerus and neck of scapular

-Reinfirced by glenohumeral ligaments and tendons of SITS muscles

Question 11

Why is the glenohumeral joint significant?

Answer 11

Inverse relationship between range of motion and stability

Question 12

Describe the glenohumeral joint

Answer 12

• Deepened by the fibrocartilaginous collar (glenoid labrum )
• Subdeltoid(subacromial) bursa allows for easy movement of the supraspinatus tendon under the coracoacromial arch and of the deltoid over the greater tubercle

Question 13

What are the main muscles acting on the shoulder?

Answer 13

Deltoid

Pectoralis major

Serratus anterior

Trapezius

Latssiumus dorsi

Teres major

Question 14

What are the functions of the rotator cuff muscles?

Answer 14

Play a major role in reinforcement of the joint capsule.

Question 15

What is the function of the deltoid?

Answer 15

Abducts arm 15 to 90 degrees

Question 16

What is the innervation of the deltoid?

Answer 16

Axillary nerve

Question 17

What is the function of the pectoralis major?

Answer 17

Flexion, adduction and medial rotation of the arm

Question 18

What is the innervation of the pectoralis major?

Answer 18

Medial and lateral pectoral nerves

Question 19

What is the function of the serratus anterior?

Answer 19

Rotates scapula upward for abduction of arm above 90 degrees

-protects the scapula

Question 20

How is the serratus anterior innervated?

Answer 20

Long thoracic nerve (C5,6,7)

Question 21

What is the function of the trapezius?

Answer 21

Assists in rotating the scapula upwards during abduction of arm above 90 degrees

Elevation of the scapula

Question 22

What is the innervation of the trapezius ?

Answer 22

Spinal accessory nerve

Question 23

What is the function of the latissimus dorsi?

Answer 23

Extends, adducts and medially rotates arm

Question 24

What is the innervation of the latissimus dorsi?

Answer 24

Thoracodorsal nerve

Question 25

What is the function of the teres major?

Answer 25

Extension, adduction, medial rotation of the arm

Question 26

What is the innervation of the teres major?

Answer 26

Lower subscapular nerve