Scapular Region Flashcards
What muscle attaches to the strenal end of the clavicle?
Pectoralis major
What muscles attach to the lateral end of the clavicle?
Trapezius
Deltoid
What is the only bone connecting the shoulder with the axial skeleton
Clavicle
What joint is the center of movement for the shoulder?
Sternoclavicular joint
Components of the sternoclavicular joint?
Articular disc
Interclavicular ligament
Anterior sternoclavicular ligament
Costoclavicular ligament
Shoulder separation
Acromioclavicular joint
When you have a fracture in the midshaft of the humerus, what nerve are you concerned about?
Radial nerve
When you have a fracture in the surgical neck of the humerus, what nerve are you concerned about?
Axillary nerve
A bursa is lined by
Synovial membrane
5 principle joints of the shoulder region
Subacromial joint
Acromioclavicular joint
Glenohumoral joint
Sternoclavicular joint
Scapulothoracic joint
Scapulothoracic joint lies between
Subscapularis and rib cage
Movements of the scapula include
Elevation and depression
Abduction and adduction
Lateral rotation of the inferior angle
Movements in the sternoclavicular joint
Elevation and depression of the shoulder
Protraction and retraction of the shoulder
The motion of the scapula is dependent on the motion of the
Clavicle
For every __ degrees of humeral motion, there is __ degree of ___ rotation
2 degrees of humeral motion
1 degree of scapular rotation
Movements of the shoulder joint
Flexion and extension
Abduction and adduction
Internal and external rotation
What happens when your shoulder dislocates?
The head of the humerus goes below the coracoid
Primary abductor of deltoid
Middle part
Function of anterior part of deltoid
Flexes and medially rotates arm
Function of posterior part of deltoid
Extends and laterally rotates arm
Rotator Cuff Muscles
Supraspinatus
Infraspinatus
Teres minor
Subscapularis
Functions of rotator cuff muscles
Primary function: holds glenohumeral joint tightly in place with continual traction
Which rotator cuff muscles insert on the greater tubercle?
Supraspinatus
Infraspinatus
Teres minor
Triangular space (boundaries)
Teres major
Teres minor
Long head of triceps
What goes through the triangular space?
Circumflex scapular artery
Quadrangular space (boundaries)
Teres major
Teres minor
Shaft of humerus
Long head of triceps
What goes through the triangular space?
Axillary nerve
Posterior circumflex humeral artery
Triangular interval (boundaries)
Teres minor
Shaft of humerus
Long head of triceps
What goes through the triangular interval?
Deep brachial artery
Radial nerve
Locations of suprascapular artery and nerve in rotator cuff
Suprascapular artery is superior (over) the transverse scapular ligament
Suprascapular nerve goes under the transverse scapular ligament
Route of suprascapular artery and nerve
Artery crosses superior to transverse scapular ligament. Nerve goes under it. They first supply the supraspinatus muscle
Artery and nerve cross lateral to the spine of the scapula
They then supply the infraspinatus
The artery goes on to supply the teres minor and anastamoses inferior to the scapula
Supraspinatus is involved as a syngerist to the ___ in ___ at shoulder
Synergist to deltoid in abduction at shoulder
Initial phase of abducitng arm (0-60 degrees)
Supraspinatus and deltoid muscles
Second phase of abducting arm (60-120 degrees)
Supraspinatus and deltoid maintain contraction
Upper trapezius and lower serratus anterior rotate shoulder point upward
Final phase of abducting arm (120-180 degrees)
Spinal cord curves to the opposite side to allow the arm to be raised completely overhead
Damage to supraspinatus tendon
Rotator cuff tear
Tendons of the rotator cuff muscles
Supraspinatus tendon
Infraspinatus tendon
Teres minor tendon
Tendon of long head of biceps
Subscapularis tendon
Ligaments that stabilize the gelnohumeral joint + strongest
Superior glenohumeral ligament
Middle glenohumeral ligament
Inferior glenohumeral ligament
Inferior = strongest
Functions of gelnohumeral ligaments
Resist abduction and lateral (external) rotation
Innervation of A/C joint
Suprascapular joint innervatoin
Some contribution from lateral pectoral nerve
What two mechanisms hold the head of the humerus into the glenoid fossa
Passive Process
Active process
Passive process
Ligaments physically hold in the shoulder joint
Active processes
Rotator cuff muscles are all active in holding head of humerus on the joint
Glenoid labrum is weakest in
Anterior superior area
Glenoid labrum is strongest
Inferior anterior area
Scapular anastamosis arteries
Transverse cervical
Dorsal scapular
Suprascapular
Circumflex scapular
Circumflex humeral
Shoulder dislocation
Glenohumeral joint