Sternoclavicular joint is 

A) Cartilaginous

B) Fibrous

C) Synovial

• Interclavicular ligament (superior - binds the two clavicles to sternum
• costoclavicular ligament (inferior - binds clavicle to 1st rib)
• anterior sternoclavicular ligament (anterior - binds to sternum)
• posterior sternoclavicular ligament (posterior - binds to sternum)

• acts as a stabilizing base/platform when significant force is being transmitted (pushup)
• enhance movements at glenohumeral joint by gliding on posterior thoracic wall

Intrinsic ligaments of the shoulder joint (6)

• glenohumeral ligaments
• transverse humeral ligament
• coracohumeral ligament
• coracoacromial arch
• supraspinatus muscle
• coracoacromial ligament

• band of fibers passing from greater to lesser tubercles
• bridges the superior end of the intertubercular groove
• converts the intertubercular groove into a canal
• canal holds the tendon of the long head of briceps brachii

• strengthens the superior part of the capsule
• passes from the lateral side of the base of the coracoid process to the anatomical neck of the humerus

• coracoid process, coracoacromial ligament, and acromion form a protective arch
• the head of the humerus is pressed against this arch when leaning on outstretched arms on desk
• the arch prevents displacement of the humeral head superiorly

• passes under arch on way to insertion on greater tubercle
• separated from arch by subacromial bursa

• strong triangular ligament form coracoid process to acromion
• part of arch

• Supraspinatus
• Infraspinatus
• Teres minor
• Subscapularis

strength of shoulder joint mainly comes from the rotator cuff muscles

• located between the tendon of the subscapularis muscle and the neck of the scapula
• communicates with shoulder capsule

• lies between the deltoid muscle and the supraspinatus tendon and joint capsule
• does not normally communicate with joint space
• facilitates the movement of the deltoid muscle over fibrous capsule and the supraspinatus tendon

• trapezius
• latissimus dorsi

• levator scapulae
• rhomboids
• serratus anterior

• deltoid
• supraspinatus
• infraspinatus
• teres minor
• teres major
• subscapularis

• trapezius
• latissimus dorsi
• levator scapulae
• rhomboid major
• rhomboid minor

• serratus anterior
• pectoralis major
• pectoralis minor
• subclavius

• rotates the scapula upward and abducts the scapula
• raises the ribs

• rotates the scapula downward
• raises the 3 ribs

• anterior surface of the sternal 1/2 of the clavicle
• anterior surface of the sternum as low as the attachment of the cartilage of the 6th rib
• from the cartilages of the 2nd to 6th ribs
• from the aponeurosis of the external oblique muscle

• flexes and adducts the shoulder
• rotates the shoulder medially

• may depress the lateral end of clavicle
• steady clavicle during movements

• Deltoid (anterior)
• Deltoid (middle)
• Deltoid (posterior)
• Teres major
• Teres minor
• Supraspinatus
• Subscapularis
• Infraspinatus

• lateral 1/3 of the clavicle

Teres Major Function (2)

adducts and extends the arm

medially rotates the arm

• laterally rotates the arm
• adducts the arm

• abducts the arm
• flexes and laterally rotates the arm

• medially rotates the arm
• flexes, extends, abducts and adducts the arm depending on arm position

• lateral rotation of the arm
• upper fibers abduct and lower fibers adduct the arm