Scapular and Pectoral Regions Flashcards
Connects UL to the axial skeleton
Clavicle and scapula
Where does the UL articular with the sternum
Sternoclavicular
Is the sternum apart of the pectoral girdle
Sternum
From manubrium of the sternum to the acromion of the scapula
Clavicle
to act as a strut for holding the UL free from the trunk so it may have maximum range of motion
Function of the clavicle
posterolateral aspect of thorax (2nd to 7th ribs) – connect the clavicle to the humerus
Scapula
Humerus Radius Ulna Carpal bones (wrist) metacarpal bones of hand phalanges (fingers)
Superior portion of appendicular skeleton
Another word for pectoral girdle
Shoulder or Shoulder girdle
2 joints of the shoulder complex
Sternoclavicular
Acromioclavicular Glenohumeral joints.
a synovial ball and socket articulation of the head of the humerus and the glenoid cavity of the scapula.
Glenohumeral joint
Multiaxial with a wide ROM usually provided at the cost of skeletal stability.
Glenohumeral joint
What provides joint stability to pectoral girdle?
- rotator cuff muscles/tendons
- long head of the biceps brachii m.
- elated bony processes
- extracapsular ligaments
flexion, extension, abduction, adduction, medial rotation, lateral rotation and circumduction.
Movements of pectoral girdle
Shoulder pads
Deltoid m
Lats little helper
Teres major m
4 muscles of the rotator cuff
- Supraspinatus m
- Infraspinatus m
- Teres minor m
- Subscapularis m
Action of the deltoid
abducts humerus (1°), flexes, extends & rotates humerus (2°)
N: Axillary n. & Post. Circumflex Humeral vessels
Deltoid muscle
What vertebrae does the axillary nerve associated with?
C5, C6
Function of Teres Major
medially rotates & extends humerus
N: Lower (inferior) Subscapular n. & subscapular vessels
Teres Major muscle
Vertebrae associated with Lower subscapular nerve
C5-C7
Where does the action of teres major occur?
Glenohumeral joint
Contributes to adduction of the humerous
Teres Major m.
Action of Supraspinatus m.
abducts humerus (1st 15°)
What innervates Supraspinatus m
- Suprascapular n. & vessels
- Dorsal scapular vessels
1st 15 degrees of abduction – initiates the abduction but doesn’t drop out when the deltoid begins acting
Supraspinatus
. The supraspinatus continues to play an active role reaching its maximum at approximately
110 deg of abduction
Action of the infraspinatus m
Laterally rotates humerus
Innervation of infraspinatus
-Suprascapular n. & vessels -subscapular vessels
Spinal level associated with Suprascapular n
C5-C6
Spinal level associated with Axillary n
C5-C6
Action of Teres minor m
Lateral rotation of humerus
Innervention of Teres minor m
- Axillary N
- Suprascapular and subscapular vessels
Action of subscapularis
Medial rotation of humerus
Innervation of subscapularis m
- Upper and lower subscapular nn
- Subscapular vessels
Helps prevent upward displacement of head of humerus
Rotator cuff
Membranous sac containing lubricating synovial fluid
Subacromial (Subdeltoid) Bursa
Inferior to acromion & deltoid but superior to supraspinatus m.
Subacromial (Subdeltoid) Bursa
Does the subacromial bursa communicate with jt. capsule?
No
Bursa that are associated with the joint but not connected to it
Subacromial bursa and Supraspinatus muscle (joint capsule)
Between the acromnion
Subacromial (subdeltoid)
What causes the subacromial bursa to be continuous with the joint
Attrition of the supraspinatus tendon
When does the supraspinatus tendon usually degenerate?
Middle age
Up to ¼ of adults rupture supraspinatus tendon by
65
What happens when capsule opens, continuous with bursa
Painful shoulder with limited arm movement
Name the 3 spaces of the shoulder region
- Quadrangular space
- Triangular space
- Triangular interval
What goes through Quadrangular space
Axillary N. and Posterior circumflex humeral a.
What does through the triangular space
Circumflex scapular a
What goes through triangular interval
Radial N. and Profunda brachii a
Muscles of the quadrangular space
- Teres minor m
- Teres major m
- Long head of triceps brachii m
What does the quadrangular space contain?
Axillary n & posterior circumflex humeral vessels
Superior border of quadrangular space
Teres minor m
Inferior border of quadrangular space
Teres major m
Medial border of quadrangular space
Long head of triceps brachii m