CH 5 Shoulder Joint
The general ratio between the glenohumeral motion and scapula motion is what
2:1
Due to the wide range of motion of the shoulder joint this requires what?
A lot of laxity
What are the agonists of glenohumeral flexion?
Anterior deltoid pectoralis major
In upper crossed syndrome what muscles are weak and inhibited?
Deep cervical flexors Serratus Anterior Rhomboids Middle/lower trap External rotators Arm extensors
What are the agonists of glenohumeral abduction?
Deltoid Supraspinatus
The difference in internal rotation range of motion between an individuals throwing and nonthrowing shoulders is what
GIRD
GIRD stands for what?
Glenohumeral internal rotation deficit
Which rotator cuff muscles perform external rotation?
Infraspinatus Teres Minor
What are the agonists of glenohumeral external rotation?
Infraspinatus teres major
The glenoid labrum enhances what by doing what?
It enhances stability by deepening the concavity of the fossa
What are the agonists of glenohumeral adduction?
Latissimus dorsi pectoralis major coracobrachialis
What are the agonists of glenohumeral internal rotation?
Latissimus dorsi theres major subscapularis pectoralis major
What are the agonists of glenohumeral extension?
Posterior deltoid latissimus dorsi
The synergistic relationship between the glenohumeral joint and shoulder girdle is called what
Scapulohumeral rhythm
What can cause injury because of the anatomical design of the glenohumeral joint?
Shallowness of the glenoid fossa Laxity of ligamentous structures Lack of strength and endurance in muscles
Repeating overhead activities can cause what kind of rotator cuff problems?
Tendinitis Rotator Cuff Impingement Failure to stabilize the humeral head
The rotator cuff is vital in maintaining what?
The humeral head in correct approximation within the glenoid fossa
In upper crossed syndrome what muscles are tight and overly faciliated?
Upper trap Levator scapula Suboccipitals Pectorals Internal rotators Arm flexors
The glenohumeral ligaments provide stability primarily in what directions?
anterior and inferior
The glenohumeral joint is what kind of joint?
ball and socket
The shoulder joint action: extension is paired with what shoulder girdle action?
depression/downward rotation
The shoulder joint action: adduction is paired with what shoulder girdle action?
downward rotation
The shoulder joint action: flexion is paired with what shoulder girdle action?
elevation/upward rotation
The shoulder joint action: horizontal adduction is paired with what shoulder girdle action?
protraction
The shoulder joint action: internal rotation is paired with what shoulder girdle action?
protraction
The shoulder joint action: external rotation is paired with what shoulder girdle action?
retraction
The shoulder joint action: horizontal abduction is paired with what shoulder girdle action?
retraction
The more mobile a joint is, the less _____________ it is
stable
Which rotator cuff muscle performs internal rotation
subscapularis
Which rotator cuff muscle initiates abduction?
supraspinatus
What does the rotator cuff consist of?
supraspinatus infraspinatus teres minor subscapularis
The rotator cuff muscles all attach where?
the front, top, and rear of the humeral head
The shoulder joint action: abduction is paired with what shoulder girdle action?
upward rotation
