Download Considered a bone of both shoulder girdle and shoulder joint. The

Considered a bone of both shoulder girdle and shoulder joint. The shoulder girdle is
comprised of the clavicle and the scapula. The shoulder joint consists of the scapula
and the humerus. The primary function of the shoulder girdle is to position itself to
accommodate movements of the shoulder joint.
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Superior angle—top point
Inferior angle—bottom point
Vertebral border—side closest to vertebral column
Axillary border—side closest to arm
Subscapular fossa—anterior fossa
Glenoid fossa, glenoid labrum, glenoid cavity --The glenoid fossa is the shallow cavity
where the humeral head goes. The glenoid labrum is the cartilage that goes around
the glenoid fossa. So the glenoid fossa and glenoid labrum together comprise the
glenoid cavity.
Supraspinous fossa—posterior, fossa above the spine
Spine of the scapula—the back projection
Infraspinous fossa—posterior depression/fossa below spine
Coracoid process—anterior projection head
Acromion process—posterior projection head above spine
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Scapulothoracic “joint” = NOT a true joint; there are no ligaments or articular
capsule. The scapula just rests on the muscle over top the rib cage, which allows for
passive movements.
Sternoclavicular joint=where the clavicle (collarbone) and the sternum (breastbone)
articulate; movement is slight in all directions and of a gliding, rotational type
Acromioclavicular joint = where the clavicle and scapula (acromion process)
articulate; AKA: AC Joint; movement is a slight gliding when elevation and depression
take place.
Glenohumeral joint = the shoulder joint
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All 3 true joints: Sternoclavicular, AC and glenohumeral (GH) all work together to
move arm in all directions. The GH allows the arm to go out to the side and be
abducted, then the AC and Sternoclavicular joints kick in to allow the arm to go above
shoulder level by allowing the shoulderblade to move up to increase the range of
motion (ROM).
The clavicle helps increase the ROM because it acts as a strut maintaining the upper
limb away from the thorax, which allows the greater ROM to occur.
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Acromioclavicular ligament—functions as the joint capsule by tying together and
totally surrounding the lateral end of the clavicle and the acromion process (scapula)
Sternoclavicular ligament—has anterior, superior, and posterior fibers to help with
the SC articulation
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Click on the hyperlink to see a shoulder injury.
A shoulder dislocation is when the humerus head comes completely out of the GH
joint—the ball comes out of the socket. This usually will occur when the arm is
abducted and in shoulder flexion (arm raised up). Once out of socket, the arm hangs
limp.
A shoulder separation is also called an AC separation. It is a separation of the
acromioclavicular joint—the clavicle separates from the acromion process of the
scapula.
A subluxation is when the shoulder comes out and then goes back in on its own. It is
typically bone rubbing on bone instead of gliding.
Some of you may have a shoulder impingement. That is when the supraspinatus
tendon is compressed between the humeral head and the acromion process, which
causes pain and weakness in the shoulder.
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The clavicle is susceptible to compressive forces and blows and will break if you fall
on an outstretched arm. Often fractured because: of its shape, held in place by
ligaments on each end, and there is little protection from outside forces.
It is the only bony attachment that the upper extremity has to the trunk. The clavicle
has a sternal end (the end that articulates with the sternum) which is bigger and an
acromial end (articulates with acromion process of the scapula) which is thinner.
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Humerus = upper arm bone
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The head fits in the glenoid cavity of the scapula. The anatomical neck is the natural
curve around the head, above the tuberosities, and the surgical neck is below them.
The greater tuberosity is the bigger bump located on the lateral side of the humerus
and the lesser tuberosity is the smaller bump on the anterior side. The
intertubercular groove is the natural line in between the greater and lesser
tuberosities. The deltoid tuberosity is a bump about ½ way down the shaft. The
capitulum is the specific name of the lateral rounded condyle and the trochlea is the
specific name of the medial pointy condyle of the humerus. The medial and lateral
epicondyles are the smaller bumps just above the condyles (capitulum and trochlea).
On the anterior side, the divot between the condyles is called the coronoid fossa; on
the posterior side there is a big divot called the olecranon fossa. The supracondylar
ridges are the edges (ridges) just above the epicondyles.
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Glenohumeral ligament—located beneath the anterior surface of the joint capsule
and helps reinforce the joint cavity (superior, middle, & inferior).
Coracohumeral ligament—goes between the anatomical neck of the humerus and
the coracoid process of the scapula.
Coracoacromial ligament—crosses between the coracoid process and the acromion
process of the scapula. This helps limit the superior movement of the humeral head.
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Ulna = “underneath” in anatomical position; the pinky finger side. The ulna is medial
to the radius. The ulna has the prominent role of articulating with the humerus.
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Olecranon process—top projection
Coronoid process—lower projection
Trochlear notch—notch in between the 2 processes
Shaft
Styloid process—point at the distal end
Radial notch—groove on the lateral side of the coronoid process where the
radius head will fit in
**The top of the Ulna forms a “C.” The top part of the “C” is the olecranon process
and the bottom part of the “C” is the coronoid process, with the trochlear notch in
the middle.**
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Radius is on the lateral side of the lower arm in anatomical position. It has the
prominent role of articulating with the bones of the wrist.
proximal rounded head
Radial tuberosity—bump below head
Styloid process of the radius—distal point
Head—
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The ulnohumeral joint is the true elbow joint—what type of joint is that??
The radiohumeral joint is where the capitulum from the humerus articulates with the
head of the radius.
Both the proximal and distal radioulnar joints (joints between the radius and ulna) are
pivot joints.
Proximal Radioulnar—head of the radius articulates with the radial notch of the ulna.
The annular ligament wraps around the radius and allows some rotation to occur.
Distal Radioulnar—distal ends of both the radius and ulna articulate
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Ulna is medial so the medial collateral ligament goes along the ulna, whereas the
lateral collateral ligament goes along the radius.
Radioulnar Ligaments—Dorsal (back of the hand) and Palmar side both have
radioulnar ligaments to connect the distal ends of the radius and ulna
Annular Ligament—wraps around radius to allow for rotation
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