Chapter 4 and 5 of Functional Anatomy

Scapulothoracic joint

Fully supported by musculature, is a pseudo-joint which means no ligaments, allows the scapula to move on the surface of the rib cage

Sternoclavicular joint (SC)

Articulates between sternum and clavicle, allows for movement of the shoulder girdle

Acromioclavicular joint (AC)

Articulates between acromion process and clavicle, allows for movement of the shoulder girdle

Purpose of shoulder girdle ligaments

Hold the clavicle down

Sternoclavicular Ligament

Connects the sternum to the clavicle, provides anterior and posterior stability

Costoclavicular and Interclavicular Ligaments

Hold the clavicle down

Acromioclavicular Ligament

Acromion process to clavicle in order to prevent dislocation

Serratus Anterior Origin

Lateral ribs 1-9

Serratus Anterior Insertion

Anterior Medial Border of scapula

Pectoralis Minor Origin

Anterior ribs 3-5

Pectoralis minor insertion

Coracoid process

Upper Trap Origin

Base of Skull

Upper Trap Insertion

Acromion process, Acromial end

Middle Trap Origin

Vertebrae C7-T4

Middle Trap Insertion

Spine of Scapula

Lower Trap Origin

Vertebrae T4-T12

Lower trap insertion

Medial Spine of scapula

Rhomboid Origin

Vertebrae C7-T5

Rhomboid Insertion

Medial Border of Scapula

Levator Scapulae Origin

Transverse Processes of vertebrae C1-C4

Levator Scapulae Insertion

Superior angle of scapula

Importance of the scapulohumeral rhythm

It allows for full range of motion with stability, for every 2 degrees of humerus movement there is 1 degree of scapula movement

Glenoid Labrum

Made of fibrocartilage, deepens glenoid fossa, acts as a valve, allows for increased contact area

Intrinsic Glenohumeral Muscles

Deltoid, coracobrachialis, teres major, rotator cuff group

Rotator Cuff group

subscapularis, supraspinatus, infraspinatus, teres minor

Extrinsic Glenohumeral Muscles

Latissimus dorsi, pectoralis major, triceps brachii, biceps brachii

Pectoralis major origin

Medial Inferior clavicle, Lateral sternum

Pectoralis Major Insertion

Lateral lip of bicipital groove

Coracobrachialis Origin

Coracoid Process

Coracobrachialis Insertion

Middle of medial border of humerus

Deltoid Origin

Anterior lateral 1/3 of the clavicle, acromion process, inferior edge of spine of scapula

Deltoid Insertion

Deltoid Tuberosity

Latissimus Dorsi Origin

Posterior Iliac Crest and sacrum, spinous process of T7-12 and L1-5, lower 3 ribs

Latissimus Dorsi Insertion

Medial Lip of Bicipital groove

Teres Major Origin

Inferior third of lateral border of scapula

Teres Major Insertion

Medial Lip of Bicipital Groove

Supraspinatus Origin

Supraspinous Fossa

Supraspinatus Insertion

Greater Tubercle

Infraspinatus Origin

Infraspinatus fossa

Infraspinatus Insertion

Posterior side of Greater Tubercle

Teres Minor Origin

Lateral Border or scapula

Teres Minor Insertion

Greater Tubercle

Subscapularis Origin

Subscapular fossa

Subscapularis Insertion

lesser tubercle

Elevation

Levator scapulae

Depression

Pectoralis Minor

Upward Rotation

Upper Trap

Downward Rotation

Rhomboid

Protraction

Pectoralis Minor

Retraction

Rhomboid

Flexion

Coracobrachialis

Extension

Latissimus Dorsi

Abduction

Middle Deltoid

Adduction

Latissimus Dorsi

Internal Rotation

Latissimus Dorsi

External Rotation

Posterior Deltoid

Horizontal Abduction

Posterior Deltoid

Horizontal Adduction

Coracobrachialis

Glenohumeral Joint Injuries (anatomical design)

Shallowness of glenoid fossa

Laxity of ligaments

Lack of strength in muscles

Glenohumeral Joint Injuries (Instability)

Anterior dislocations are common

posterior dislocations are rare

Glenohumeral Joint Injuries (Impingement)

Excessive rubbing of muscles on acromion process