what is the purpose of the shoulder?
- UE movement
- Interaction with the environment (ADLs)
what bones are involved in the shoulder?
humerus and scapula
identify the landmarks of the humerus
- head
- greater tubercle
- lesser tubercle
- intertubercular groove
- deltoid tuberosity
identify the landmarks of the scapula
- acromion process
- coracoid process
- spine
- fossae
- glenoid
- supraspinous
- infraspinous
- borders
- angles
what joint is the shoulder joint referred to?
glenohumeral joint
what kind of joint is the glenohumeral joint and what ligaments are involved?
- Multiaxial ball and socket
- Glenohumeral ligament and
coracohumeral ligament - Glenoid labrum
what is the glenoid labrum?
the ring of cartilage that lines the shoulder socket
what is the purpose of the glenoid labrum?
- Purpose: enhance stability, deepen fossa concavity
- Buttress to limit humeral head translation
stability vs mobility
- Stability = ability to maintain control and support joints during movement
- Mobility = ability to move freely and easily
As mobility increases, stability decreases
Instability issues include: subluxation, dislocation, labral tears, and rotator cuff impingement
intrinsic vs extrinsic GH muscles
intrinsic: origin = scapula and clavicle
extrinsic: origin = not scapula and clavicle
what are the intrinsic GH muscles?
- Deltoid
- Coracobrachialis
- Teres major
- Rotator cuff
what are the extrinsic GH muscles?
- Latissimus dorsi
- Pectoralis major
what is the deltoid origin, insertion, movement, and innervation?
- Origin:
Lateral clavicle
Acromian
Inferior edge spine of scapula - Insertion:
Deltoid tuberosity - Shoulder movement:
Ant fibers - ABD, horizontal ADD, flexion, IR, diagonal ADD
Post fibers - ABD, horizontal ABD, extension, ER, diagonal ABD
Middle fibers - ABD
- Innervation:
C5-C6
Axillary nerve
what is the pectoralis major origin, insertion, movement, and innervation?
- Origin:
Medial clavicle
Costal cartilages 1-6
Sternum - Insertion:
Lateral lip-intertubercular groove - Shoulder movement:
Upper fibers - horizontal ADD, IR, diagonal ADD
- flexion, ABD (>90 degrees), ADD (<90 degrees)
Lower fibers - horizontal ADD, IR, diagonal ADD
- ext (from flexed position), ADD
- Innervation:
C5-T1
Medial and lateral pectoral nerve
what is the latissimus dorsi origin, insertion, movement, and innervation?
- Origin:
Posterior iiac crest
Sacrum and SP T7-L5
Ribs 10-12 - Insertion:
Medial lip - intertubercular groove - Shoulder movement:
ADD
Ext
IR
Horizontal ABD - Innervation:
C6-C8
Thoracodorsal nerve
what is the teres major origin, insertion, movement, and innervation?
- Origin:
Lateral border of the scapula - Insertion:
Medial lip - intrtubercular groove - Shoulder movement:
Ext
IR
ADD - Innervation:
C5-C6
Lower subscapular nerve
what is the coracobrachialis origin, insertion, movement, and innervation?
- Origin:
coracoid process - Insertion:
Humeral shaft - Shoulder movement:
Flex
ADD
Horizontal ADD
Diagonal ADD - Innervation:
C5-C7
musculocutaneous
what are the rotator cuff muscles?
- Supraspinatus
- Infraspinatus
- Teres minor
- Subscapularis
what is the supraspinatus origin, insertion, movement, and innervation?
- Origin:
Infraspinous fossa - Insertion:
Greater tubercle posteriorly - Movement:
ER
Horizontal ABD
Ext
Stabilizes humeral head in glenoid fossa - Innervation:
C5-C6
Suprascapular nerve
what is the teres minor origin, insertion, movement, and innervation?
- Origin:
Lateral scapular border - Insertion:
Greater tubercle posteriorly - Shoulder movement:
ER
Horizontal ABD
Ext
Diagonal ABD
Stabilizes humeral head in glenoid fossa - Innervation:
C5-C6
Axillary nerve
what is the subscapularis origin, insertion, movement, and innervation?
- Origin:
Subscapular fossa - Insertion:
Lesser tubercle - Shoulder movement:
IR
ADD
Ext
Stabilizes humeral head in glenoid fossa - Innervation:
C5-C6
Upper and lower subscapular nerves
describe the shoulder movement: Flexion
forward movement - 180 degrees
describe the shoulder movement: Extension
backward movement - 60 degrees
describe the shoulder movement: Abduction
upward lateral movement/away from body - 180 degrees
