Glenohumeral Joint, Pectoralis Major, and Coracobrachialis

1. Glenohumeral Joint, Pectoralis Major, and Coracobrachialis

2. Bones of the GH Joint • The GH joint is formed between two bones, the humerus and scapula • The GH joint is like a golf ball on a tee: the golf ball is the head of the humerus and the tee is the Glenoid Fossa • The Glenoid Fossa is the socket or cavity at the end of the scapula • The humerus head does not fit perfectly within the glenoid fossa because the humerus head is much larger than the surface area of the glenoid fossa • The glenoid fossa is only one-fourth the size of the humeral head • The two bones do not snugly fit together without cartilage, muscles, and ligaments

4. Cartilage • The most important piece of cartilage of the GH joint is the Glenoid Labrum • The Glenoid Labrum lies directly between the humerus head and the glenoid fossa

5. Glenoid Labrum • It is shaped like a ring, with the outer part of the labrum being much thicker than the center of the ring

6. Glenoid Labrum • This specific shape allows for the labrum to fit against the humerus head • Glenoid labrum deepens the glenoid fossa providing a smooth surface that allows for the humerus head to rotate with minimal friction, thus cushioning both the humerus and the scapula • The labrum is very important for the stabilization of the joint

7. Glenoid Fossa Glenoid Labrum

8. Glenohumeral (GH) Function • Tri-axial synovial ball-and-socket joint that allows the humerus to move in all three planes of motion • Most freely movable joint • Lacks stability • The motion that it provides is flexion, extension, abduction, adduction, medial rotation, lateral rotation, horizontal adduction, horizontal abduction, and circumduction

9. Humerus Key Bony Landmarks (Palpate) • Head-proximal end of the humerus • Greater Tubercle-located just below the acromion process of scapula • Lesser Tubercle-located anteriorly and medial to the greater tubercle • Intertubercular Groove-laterally rotate shoulder and it is located just below the greater tubercle of humerus

12. Muscles That Move The Glenohumeral Joint Rotator Cuff Muscles: Supraspinatus Infraspinatus Teres minor Subscapularis • Pectoralis Major • Coracobrachialis • Deltoids • Latissimus Dorsi • Teres Major • Biceps Brachii • Triceps Brachii

15. Pectoralis (Chest) Major (Larger) • Thick fan shaped muscle located on the anterior chest wall • It makes up the bulk of the chest muscles in the male and lies under the breast in the female. • Two heads: Clavicular and Sternal • Clavicular head is located on the medial clavicle and upper sternum • Sternal head is located on the sternum, upper six ribs, and aponeurosis of external oblique • The fibers meet toward their insertion • The fibers end in a flat tendon

16. Pectoralis Major • O: Sternum, Clavicle, and Costal Cartilages of Ribs #1-6 • I: Intertubercular Groove (Bicipital Groove) of Humerus • A: Shoulder Flexion • Shoulder Adduction • Shoulder Medial Rotation • Shoulder Horizontal Adduction

17. Integrated Function of Pectoralis Major • Assists in eccentric deceleration of shoulder extension • Assists in eccentric deceleration of shoulder horizontal abduction • Assists in eccentric deceleration of shoulder lateral rotation • Assists in dynamic stabilization of the shoulder during overhead movements

18. Coracobrachialis • Coraco: refers to the coracoid process of the scapula • Brachialis: refers to the arm • Coracoid process is a hook like structure located on the anterior surface of the scapula medial to the glenoid fossa

19. Coracobrachialis • O: Coracoid Process of Scapula • I:Medial Surface of humerus shaft • A: Shoulder Flexion • Shoulder Adduction • Shoulder Horizontal Adduction

20. Integrated Function of Coracobrachialis • Assists in eccentric deceleration of shoulder extension • Assists in eccentric deceleration of shoulder abduction • Assists in dynamic stabilization of the shoulder

21. BB/DB Bench Press, Flyes, Pec Dec Exercises • Bench Press and Flyes Contraindications: • Depth of the movement, position of the spine, placement of the feet, position of the head, and movement of the Scapula  • Pec Dec Contraindications: • Arm positioning - its effect on the shoulder joint and effectiveness of the exercise

22. BB/DB Bench Press • Extreme angles at the GH Joint under load are not advisable nor are they necessary • Improper Cues: “bar should be one inch above the chest”, “fist distance”, or “upper arms parallel to the floor”, “keeping the lower back flat and the feet up (on the bench or in the air) in order to protect the spine” • Starting Position: The lifter lies in a supine position with the feet in contact with the ground to provide a stable base of support • The hips, shoulders and head should remain in contact with the bench throughout!

23. BB/DB Chest Press • If the bench is too high – use a step • Ideally, your heels should be positioned 90 degrees under your knees, and your feet should be just slightly wider than your hips and flat on the floor to be properly balanced • Hand Grip Placement: Shoulder Width • For Optimum Pectoral Involvement: Retract and Depress the Scapula throughout • The wrists should be firm and straight and the forearms almost perpendicular to the floor • At the bottom of the descent the barbell should be parallel to the floor and the elbows are flexed to 90 degrees

24. DB/BB Chest Press • Spotting the BB Chest Press: • The spotter should stand behind the lifter • The spotter should use a closed alternated grip inside the hands of the lifter • Spotting the DB Chest Press: • Spotter is behind the lifter • Keep the hands near the client’s wrist as the DB’s descend and ascend

25. BB Chest Press • If your clients have painful shoulders when bench pressing they may need to stop using a BB • To safely return to chest pressing, follow these guidelines: • Perform Rotator Cuff Strengthening Exercises • Use DB’s or Cables instead of a BB • Dumbbells and Cables allow your body the needed freedom of motion to find a new bench press pathway that does not stress the shoulder

26. Pec Dec • Contraindicated Exercise due to terminal lateral rotation and abduction of the GH joint • It places the shoulder in extreme positions under load but it also inhibits a large percentage of pectoral involvement  • It also encourages a kyphotic posture – forward head and rounded shoulders

27. DB Fly • Starting Position: The lifter lies in a supine position with the feet in contact with the ground to provide a stable base of support • The hips, shoulders and head should remain in contact with the bench throughout! • Retract and Depress the scapula throughout • Keep the elbows slightly flexed • Maintain firm and straight wrists • Lower the shoulders in a controlled manner • Lower the shoulders until they are parallel with the floor and elbows are flexed to about 90 degrees

28. DB Fly • Spotting: • Spotter is behind the lifter • Keep the hands near the client’s wrist as the DB’s descend and ascend • Because the elbow is stabilized, there is potentially more stress at the shoulder, elbow, and wrists • Do not let the shoulders descend beyond parallel to the floor • Not a safe exercise for the GH joint • Better option would be to perform a standing cable fly (you are working with gravity) which reduces the stress on the shoulder, elbow, and wrist

29. Push Up • Contraindications: • Faulty Spinal Alignment-very common and generally caused by a lack of general body awareness, trunk strength and postural stability • Can appear as: • Sagging head • Sagging back (lordosis) • Hunching back (kyphosis) • Any combination of the above • Sometimes people will begin with ideal alignment and gradually lose alignment as the exercise progresses and fatigue sets in

30. Push Up • Possible solutions to faulty spinal alignment: • Build Body Awareness (proprioception)- perform drawing in in a quadruped position • Similar to a push up position and forces you to become aware of proper spinal alignment • Perform elbow planks-this increases postural stability and endurance necessary to perform the push up successfully • Perform incline push ups on a Smith Machine-oncesomeone can perform 20 quality reps at one height, simply lower the bar one or two pegs. The lower the bar gets, the harder the push up becomes

31. DB/BB Chest Press and Push Up • Plane of Motion: Transverse • Joint Actions (concentric phase): • Glenohumeral Horizontal Adduction • Scapulothoracic Protraction • Humeroulnar Extension • Primary Muscles Strengthened: • GH Joint: Pectoralis Major, Coracobrachialis, and Anterior Deltoid • Scapulothoracic Joint: Serratus Anterior and Pectoralis Minor • Humeroulnar Joint: Triceps Brachii and Anconeus

32. SB Kneeling Chest Stretch • Start in a quadruped position • Place your forearm on the ball with your palm down and shoulder parallel to the floor • Maintain optimal posture and hold

33. Standing Chest Stretch Against Wall • Stand against wall and form a 90-90 degree angle at the elbow and shoulder • Maintain optimal posture and hold

34. Lie incline on a SB Retract your scapula Bring the elbows back Once your elbows have traveled as far as they actively can, GENTLY assist a few degrees further. Hold for 1-2 seconds, relax, and repeat reps Chest Stretch Incline on SB

35. Supine on Foam Roll Chest Stretch • Lie supine on foam roll • Laterally rotate shoulders at about 45 degrees from head • Push back of hands toward floor