Chapter 5---- The Shoulder Joint-----Functional A&P

SC joint (Sternoclavicular joint)

Shoulder joint is attached to axial skeleton via the clavicle at the ___________________________________.

Humerus (funny bone)

Scapula movement usually occurs with movement of __________________________ bone.

Scapula

Humeral flexion & abduction require _____________________ elevation, rotation upward & abduction. Name the bone.

Humeral (humerus bone)

________________________ adduction & extension results in scapula depression, rotation downward & adduction. Name the bone.

Laxity (looseness)

Wide range of motion of the shoulder joint in many different planes requires a significant amount of __________________________ in the joint.

Stability

Subluxations (partial dislocation of a joint) & dislocation are

the price of mobility is reduced ____________________________ in the shoulder joint.

Scapula, clavicle, & humerus

__________________________________________serve as attachments for shoulder joint muscles. Name the 3 bones.

Glenoid cavity (fossa)

The head of the humerus articulates with what landmark of the scapula?

Fossa

A________________________________ is a depression or hollow area in a bone, serving various functions such as muscle attachment and housing structures like nerves and blood vessels.

Acromion process

_______________________________________________extension of the scapula, which forms the superior point of the shoulder. This is the point of articulation with the clavicle to form the AC joint.

Glenoid fossa (cavity)

The part of the scapula that joins with the humeral head to form the glenohumeral joint.

Spine of the scapula

The ____________________________ of the scapula is a prominent bony ridge on the posterior surface of the scapula that separates the supraspinous fossa from the infraspinous fossa and serves as an attachment point for several muscles.

Glenohumeral Joint

The synovial ball-and-socket joint of the shoulder

Ligaments

Glenohumeral ________________________________ provide stability

especially anteriorly & inferiorly to the shoulder joint.

Labrum

The shoulder __________________________________ is a thick piece of tissue attached to the rim of the glenoid cavity that helps keep the ball of the joint in place. The _________________ can tear a few different ways: 1) completely off the bone, 2) within or along the edge of the labrum, or 3) where the bicep tendon attaches.

Shallowness

Glenohumeral Joint:

Frequently injured due to anatomical design of

________________________________ of glenoid fossa. Also, injuries occur due to looseness of a ligaments.

Glenohumeral internal rotation deficit (G I R D)

______________________________________________difference in internal rotation range of motion between an individual's throwing & nonthrowing shoulders.

20%

Overhead athletes with a G I R D of greater than ___________% had a higher risk of injury (loss of _________________________degrees).

Abduction

Upward lateral movement of humerus out to the side, away from body

Adduction

Downward movement of humerus medially toward body from abduction

Originate on scapula & clavicle

Intrinsic glenohumeral muscles: Where do they originate?

latissimus dorsi & pectoralis major

Extrinsic glenohumeral muscles: Name the two.

Deltoid Muscle

Movement of the shoulder joint and arm:

Anterior fibers: abduction, flexion, horizontal adduction, diagonal adduction & internal rotation-------Posterior fibers: abduction, extension, horizontal abduction, diagonal abduction & external rotation_______________Middle fibers abduction------- what muscle does this?

Subscapularis, supraspinatus, infraspinatus & teres minor

Name the 4 muscles of the rotator cuff.

Rotator cuff

Conducting repetitious overhead activities (throwing, swimming & pitching) with poor technique, muscle fatigue or inadequate warm-up & conditioning leads to failure of ______________________ muscle group in dynamically stabilizing humeral head in glenoid cavity.

Brachial plexus

All shoulder joint muscles are innervated from the______________.

Brachial plexus

Network of interlacing nerves found in the upper arm area

Agonists

___________________________________are muscles whose contraction moves a part of the body directly like the anterior deltoid and the upper pectoralis major. They are the primary muscles responsible for producing a specific movement during physical activity.

Antagonist

______________________________ muscles are pairs of muscles that work in opposition to each other, playing a crucial role in facilitating smooth and controlled movements in the body.