Shoulder complex ● Freely movable ● Subject to a lot of injuries in some sports ● Older people: a lot of overhead movements ● 4 joints Movements of the shoulder ● GH- glenoid fossa and head of humerus (arm movement) ● ST- scapula throxic (movement inside that you can not see) ● Glenoid fossa- built for mobility not for stability ➔ Loose ball and socket ➔ Hip tight ball and socket Bones ● Humerus ● Scapula ● Clavicle Articulations ● There are 4 articulations that make up the shoulder complex: 1. Glenohumeral joint (GH) 2. Acromioclavicular joint (AC) 3. Sternoclavicular joint (SC) 4. Scapulothoracic joint (ST)- not a true joint Ligaments and Stabilization of the GH articulation ● Gleno- humeral ligament ● Capsular sleeve ● Rotator cuff tendons (Sits Muscles)- act like ligaments ★ Keep arm attached
AC Ligament ● Acromio Clavicular ligament ● Coraco Clavicular Ligament ➔ 2 major ligaments that hold down the clavicle SC ligament
● Streno Clavicular ligament ● Number one bone that can break because it’s not protected by muscle Cartilage ● Glenoid fossa ● Glenoid labrum- cup on the fossa; like a suction cup, its vacuum tight Shoulder Bursa ● All joints have bursa sac ● Lubricate the joint
● As you get older they get dry and get sticky ● Best thing to prevent drying is movement What are they? Why? ● Fibrous pockets that contain a lubricating fluid ● Decrease irritating effects of friction ● Build of friction between bones and tendons, skin and bone, muscle and bone ● Found near a tendon insertion and between muscle layers Shoulder Bursae ● Subacromion ● Subdeltoid ● Subscapularis
Bursitis ● Bursa- loose and thin! What happens with age? Tight, thick and dry ● What happens with injury?- become filled with scar tissue from previous injuries- especially people with atrophy or overuse in athletes ● Inflammation and swelling frequently accompany degeneration ● When felt the most??- infection or pinch of abduction Elevation of the arm allows contact between muscles and adjacent structures ● Sometimes it’s the tendon ● Same treatment for bursitis and tendonitis ● Same pain for older people and athletes Rotator Cuff ● Sits muscles ➔ Hold the head of the humerus ● Supraspinatus ➔ One on top of shoulder (abduction) ● Infraspinatus ● Teres minor ➔ Work together with infraspinatus and are external rotators; located in the back ● Subscapularis ➔ In front; internal rotator
● Rotational functions on the humerus ● Their tendons are interwoven into the capsule to form a muscule/tendinous cuff around the joint ● Stabilize the joint against dislocation ● Deep muscles and are small ● Overhand patterns of exercise Abduction and external rotation, high velocity, great force and repetition- carries the risk of tear ● Individuals return after surgery?
- Fall '19
- ● Scapula