Shoulder region and arm I

Question 1

what constitutes the upper limb

Answer 1

shoulder, arm, forearm, hand

Question 2

what is the pectoral girdle

Answer 2

bit which connects the upper limb to the thorax

Question 3

Which bones make up the pectoral girdle and list its features and be able to label

Answer 3

Clavicle-acromial facet, trapezoid line, conoid tubercle, subclavian groove, sternal facet. Long bone but no medullary (marrow) cavity, trabecular surrounded by compact shell
Manubrium sterni
Scapula-superior, lateral and medial border, superior, inferior and lateral angle, suprascapular notch, glenoid cavity (articulation site humerus), neck, acromion (clavicle articulation), coracoid process, supraspinous fossa, infraspinous fossa, spine

Question 4

Sternoclavicular joint attachment

Answer 4

clavicle connected to manubrium by anterior sterno-clavicular lig. anatomically a saddle joint but functionally a synovial ball and socket joint
Costoclavicular lig. attach clavicle to 1st rib

Question 5

Acromio-clavicular joint attachment

Answer 5

the coracoclavicular ligaments (trapexoid and conoid ligament) attach to clavicle. Conoid lig. attach to conoid tubercle
acromioclavicular lig. attach acromium to clavicle
incomplete articular disc, no muscles connect articulating bone

Question 6

What are the range of movements of the scapulothoracic joint

Answer 6

elevation, depression,retraction, protracction, upward rotation, downward rotation (this is a physiological join, it doesn’t properly articulate

Question 7

What are the deep (state where arise) and superficial back muscles and its function

Answer 7

Deep: levator scapulae C1-4, rhomboid minor C7-T1, rhomboid major T2-T5, These attach to medial border of scapula and elevate, retract and rotate scapula. Serratus anterior attach to lateral border of scapula to 1-9th rib, protracts and rotates scapula (boxer’s muscle).
Superficial: trapezius elevates, retracts and depresses scapula, latissimus dorsi (connects vertebra to upper limb) extends, adducts, medially rotates the humerus (GH joint) e.g. chin ups, pull ups

Question 8

What are the 3 parts of pec major

Answer 8

clavicular head, sternocostal head, abdominal part

Question 9

What does poland’s syndrome involve

Answer 9

very little pec major

Question 10

what are the deep anterior axio-appendicular muscles

Answer 10

subclavius (rib3-5 attachment), pectoralis minor

Question 11

What are the movements of the glenohumeral joint

Answer 11

abduction, adduction, flexion, extension, medial rotation, lateral rotation, circumduction

Question 12

When you raise arm, what needs to rotate and to what extent

Answer 12

Iniially 60 deg scapula rotation followed by 120deg glenohumeral joint

Question 13

Label the gleno-humeral joint and its articulation. List functions of features

Answer 13

ref. notes
subacromial bursa allows smooth movement, prevents ligament and bone grating
acromion=protective structure for shoulder
glenoid labrum=lid of articular cartilage
articular capsule=bulging out for abduction and arm up, otherwise tear

Question 14

Why is the head of humerus bigger than glenoid cavity

Answer 14

decreasing articular surface allows for greater freedom of movement. The stability is sacrificed

Question 15

List and label the lig. supporting the gleno-humeral joint

Answer 15

coracoclavicular, coraco acromial, acromioclavicular, coracohumeral (covered by fibrous capsule), glenohumeral (superior, middle, inferior)

Question 16

What are the muscles at the glenohumeral joint

Answer 16

deltoid, supraspinatus, infraspinatus, teres major, teres minor, subscapularis

Question 17

What are the functions of the deltoid muscle

Answer 17

clavicular (anterior)->flex and medially rotate arm
acromial (middle)->abduct arm
spinal (posterior)->extends and laterally rotate arm
engage all 3 for max abduction

Question 18

What are the functions of the following posterior muscles at the GH joint: supraspinatus, teres minor, teres major, infraspinatus

Answer 18

Supraspinatus-initiates abduction of arm
teres minor-laterally rotates arm
teres major-medially rotates arm
infraspiantus-laterally rotates arm

Question 19

What does the subscapularis do and where is it

Answer 19

On anterior surface and it medially rotates arm

Question 20

What constitutes the rotator cuff muscle

Answer 20

SITS (supraspinatus, infraspinatus, teres minor, subscapularis) coracoacromial arch gives degree of stability