Shoulder Anatomy & Motions

Bones

100

Shoulder blade

Scapula

200

Upper arm bone

Humerus

300

"Socket" of the shoulder joint

Glenoid

400

Narrow ridge on the back of the shoulder blade

Spine of the Scapula

500

Top outer edge of your scapula

Acromion

Joints

100

Breastbone and collarbone, near center of the chest

Sternoclavicular joint

200

lateral clavicle and acromion, lateral shoulder area

Acromioclavicular joint

300

The proximal humerus and scapula, multi-axial

Glenohumeral joint

400

Formed by the convex surface of the posterior thoracic cage and the concave surface of the anterior scapula

Scapulothoracic joint

500

The more MOBILITY a joint has, the less ___________

STABILITY (glenohumeral joint is very mobile, and very unstable)

Muscles

100

Muscle on anterior upper arm, has 2 heads, helps with elbow flexion (curls) and shoulder flexion

Biceps

200

Group of 4 muscles that provide dynamic stability to glenohumeral joint

Rotator Cuff Muscles

300

Rotator cuff muscle: "Superior to the Spine of the scapula"

Supraspinatus

400

Rotator cuff muscle: "Inferior to the Spine of the Scapula"

Infraspinatus

500

Rotator cuff muscle: "Under the Scapula"

Subscapularis

Other Structures

100

Thick rubbery tissue on the ends of the bones

Articular cartilage

200

Fluid-filled sac that cushions and lubricates the joint

Bursa

300

The rim of cartilage around the edge of glenoid fossa, deepens cup to hold humeral head in place

Glenoid Labrum

400

A pale liquid that lubricates articular surface & reduces friction

Synovial fluid

500

The tear of tissue that is located on top of the shoulder

Superior Labrum Anterior Posterior (SLAP) tear

Motions

100

Raising the arm up in front of the body

Flexion (Biceps muscle group)

200

Raising the arm out to the side, away from the midline

Abduction (Deltoid muscle)

300

Rotating the humerus laterally

External Rotation (Supraspinatus, Infraspinatus, Teres Minor)

400

Rotating the humerus medially

Internal Rotation (Subscapularis)

500

The efficient movement of the shoulder blade during humeral abduction is called:

Scapulohumeral Rhythm