Exam 3: Gleno-humeral Joint

Question 1

How is the glen-humeral joint formed?

Answer 1

By the head of the humerus with the glenoid cavity of the scapula

Question 2

True of False: The gleno-humeral joint has sacrificed stability for mobility.

Answer 2

True

Question 3

The glen-humeral joints lack of stability is demonstrated by what 4 factors.

Answer 3

• Lack of osseous support.
• Lack of ligamentous support.
• Lack of surrounding muscle support.
• Structure of joint capsule.

Question 4

Explain the glen-humeral joints lack of osseous support.

Answer 4

• Large head of humerus does not fit into small glenoid fossa
• Impossible for bones to be congruent with each other

Question 5

Explain the gleno-humeral joints lack of ligamentous support.

Answer 5

• only two main ligaments act on this joint
• the are positioned anterior and superior

Question 6

Explain the glen-humeral joints lack of surrounding muscle support.

Answer 6

• muscles are positioned anterior, superior, and posterior to joint

Question 7

Explain the glen-humeral structure of the joint capsule.

Answer 7

• superior capsule is taut
• inferior capsule is loose

Question 8

Explain and visualize the glenoid labrum.

Answer 8

• it is a fibrocartilage structure that rims the glenoid fossa
• it deepens the curvature of the fossa
• it is synovium lined
  *

Question 9

Explain and visualize the glenohumeral Bursae.

Answer 9

• consist of subacromial and subdeltoid
• functions to allow smooth gliding of lower structures from upper structures
  
  • g-h head to deltoid
• impingement and inflammation causes pain and swelling
  
  • this limits g-h motion

Question 10

Explain and visualize the G-H Joint capsule.

Answer 10

• Surrounds the entire joint
• larger than humeral head to allow movement of g-h head away from glenoid fossa
• taut superiorly
• loose inferiorly

Question 11

Explain and visualize the coracoacromial arch.

Answer 11

• formed by acromion process, coracoacromial ligament and coracoid process
• serves to protect head of humerus, muscles, tendons, and bursae from direct trauma
• helps prevent superior dislocation

Question 12

Visualize and explain glenohumeral ligament.

Answer 12

• three bands that form “Z” on anterior capsule
• bands tighten and provide “check” to certain humeral motions
• all bands taut on lateral rotaion
• middle and inferior bands taut during abduction

Question 13

Know and visualize coracohumeral ligament

Answer 13

• consist of anterior and posterior bands
• provides passive support of upper extremity when arm is in dependent position
• checks lateral rotation
• anterior band tight during humeral extension
• posterior band tight during humeral flexion

Question 14

Know the rule of 1/3 in joint ROM of glenohumeral joint

Answer 14

• 1/3 degrees from scapulothoracic joint
• i.e. flexion 180: 1/3 of 180 is 60 degrees from scapulothoracic.

Question 15

glenohumeral flexion

Answer 15

hand beings at side, moves to shoulder, to overhead

Question 16

glenohumeral extension

Answer 16

backward movement of arm taking hand posterior to body

Question 17

glenohumeral adduction

Answer 17

arms at side

Question 18

glenohumeral abduction

Answer 18

arms moves up from side

Question 19

glenohumeral internal rotation

Answer 19

head of humerus turns anteriorly

Question 20

gleno humeral external rotation

Answer 20

head of humerus turns posteriorly

Question 21

glenohumeral horizontal adduction

Answer 21

arm at shoulder level, moving towards midline

Question 22

glenohumeral horizontal abduction

Answer 22

arm at shoulder, moves posteriorly

Question 23

glenohumeral diagonal adduction

Answer 23

from full flexion, arm brought down across body

Question 24

glenohumeral diagonal abduction

Answer 24

from diagonal adduction, arm brought to full flexion

Question 25

Pectoralis major muslce Action

Answer 25

Humeral Flexion Humeral Adduction Humeral horizontal adduction humeral internal rotation humeral extension diagonal adduction i.e. putting on earrings, pulling up sleeves, Saturday night fever disco dance

Question 26

Anterior Deltoid muscle Action

Answer 26

humeral flexion humeral horizontal adduction humeral internal rotation fusiform muscles styling hair, brushing teeth, hands behind head, addressing front of body

Question 27

Coracobrachialis muscle action

Answer 27

humeral horizontal adduction humeral flexion humeral adduction humeral internal rotation shunt muscle pulls humerus up; lifting up suitcase

Question 28

subscapularis muscle action

Question 29

biceps brachii

Answer 29

muscle of elbow and forearm shunt muscle for stability humeral flexion horizontal adduction

Question 30

Middle Deltoid muscle

Question 31

supraspinatus muscle

Answer 31

humeral abduction

Question 32

posterior deltoid muscle

Question 33

latissimus dorsi muscle

Question 34

teres major muscle

Answer 34

"little helper" of latissimus dorsi humeral adduction humeral extension and hyperextension humeral internal rotation "mini" latts, does everything latts do but not as strong

Question 35

infraspinatus and teres minor muscle

Question 36

long head of the triceps muscle

Question 37

Guardians of the shoulder- rotator cuff muscles

Answer 37

SSIT Subscapularis supraspinatus infraspinatus teres minor

Question 38

SSIT muscles

Answer 38

act as dynamic ligaments for shoulder joint attaches at humeral head contract to keep head congruent with glenoid cavity

Question 39

axiohumeral muscles

Answer 39

orginate on axial skeleton, insert on humerus draws humerus close to body pectoralis major latissimus dorsi

Question 40

scapulohumeral muscles

Question 41

axioscapula muscles

Question 42

disorders of shoulder complex

Answer 42

bursitis rotator cuff tear shoulder dislocation/seperation frozen shoulder

Question 43

frozen shoulder

Answer 43

joint capsuler becomes thick and tight stiffness and pain in shoulder symptoms being gradually and worsen can occur with no cause

Question 44

progression of frozen shoulder (adhesive capsulitis)

Answer 44

painful/freezing stage : motion restricted; omst painful frozen stage: less pain, more stiffness thawing: motion returns; can last more than one year