Question Answer
Humerus Is the largest and longest bone of the upper limb. It articulates with the scapula (shoulder blade) at the shoulder joint.
Proximal humerus Is the part of the upper arm that articulates with the scapula, making up the shoulder joint.
Head of humerus proximal part
anatomic neck the slightly constricted area directly below and lateral to the head
lesser tubercle the process directly below the anatomic neck on the anterior surface
greater tubercle the larger lateral process. which the pectoralis major and supraspinatus muscles attach
intertubercular groove the deep groove between these the greater and lesser tubercles
surgical neck the tapered area below the head and tubercles. is so named because it is the site of frequent fractures requiring surgery
body distal to the surgical neck is the long (shaft)
deltoid tuberosity is the roughened raised triangular elevation along the anterolateral surface of the body (shaft) to which the deltoid muscle is attached.
the relative location of the greater and lesser tubercles is significant in determining a true frontal view or a true AP projection of the proximal humerus lesser is located anteriorly and the greater is located laterally in a true AP projection
shoulder girdle consist of 2 bones:
clavicle and scapula
function of shoulder girdle is to connect each upper limb to the trunk or axial skeleton.
anteriorly the shoulder girdle connects to the trunk at the upper sternum
posteriorly the shoulder girdle connects to the trunk is incomplete because the scapula is connected to the trunk by muscles only.
scapula upper margin is at the level of the 2nd posterior rib. lower margin is at the level of the 7th posterior rib (T7)
clavicle long with a double curvature with 3 main parts: 2 ends and the long central portion.
lateral or acromial extremity (end) of the clavicle articulates with the acromion of the scapula.
acromioclavicular joint generally can be readily palpated
medial or sternal extremity (end) articulates with the manubrium, which is the uper part of the sternum.
sternoclavicular joint also is easily palpated and the combination of the sternoclavicular joints on either side of the manubrium helps to form an important positioning landmark called the jugular notch
female clavicle shorter and less curved than the male clavicle
scapula has 3 angles and 2 surfaces: medial vertebral border which is the long edge or border near the vertebrae; superior border uppermost margin and lateral (axillary) border nearest the axilla.
lateral angle sometimes called the head of the scapula is the thickest part and ends lateraly in a shallow depression called the glenoid cavity (fossa)
glenohumeral joint or shoulder joint also known as the scapulohumeral joint
the superior and inferior angles refer to the upper and lower ends of the medial or vertebral border.
the body (blade) of the scapula is arched for greater strength
anterior surface of scapula is termed the costal surface because of its proximity to the ribs.
mid area of the costal surface presents a large concavity or depression, the subscapular fossa
acromion is a long, curved process that extends laterally over the head of the humerus.
coracoid process is a thick, beaklike process that projects anteriorly beneath the clavicle.
scapular notch is a notch on the superior border that is partially formed by the vase of the coracoid process.
spine a prominent structure on the dorsal or posterior surface of the scapula
acromion overhangs the shoulder joint posteriorly
crest posterior border or ridge of the spine is somewhat thikened
infraspinous and supraspinous fossa is seperated on the posterior surface. Both of these fossae serve as surfaces of attachment for shoulder muscles.
LATERAL VIEW the thin scapula looks like the letter "Y" in this position. uppper parts of "Y" are the acromion and coracoid process. ACROMION is the expanded distal end of the spine that extends superiorly and posteriorly to the glenoid cavity.
XXXXX CORACOID process is located more anteriorly in relationship to the glenoid cavity or shoulder joint. Bottom of the "Y" is the body of the scapula
CLASSIFICATION OF JOINTS shoulder girdle: sternoclavicular joint, acromioclavicular joint and scapulohumeral joint. Classified as synovial joints
mobility type freely movable or diarthrodial. The only difference betwwen these 3 joints is their movement type.
SCAPULOHUMERAL (GLENOHUMERAL) OR SHOULDER JOINT articulation between the head of the humerus and the glenoid cavity. movement type is a spheroidal (ball and scoket) joint great freedom of movement. flexion, extension, abduction, adduction, circumduction & medial(internal) and lateral (external) rotatio
STERNOCLAVICULAR JOINT is a couble plane or gliding joint because the sternal end of the clavicle articulates with the manubrium or upper portion of the sternum. This allows a limited amount of gliding motion in nearly every direction.
ACROMIOCLAVICULAR JOINT is also a small synovial joint of the plane or gliding, movement type between the acromial end of the clavicle and the medial aspect of the acromion of the scapula.
Proximal humerus rotation Proximal rotational of humerus or shoulder girdle are commonly taken when nontrauma is ruled out.
AP projection of humerus AP rotational projections delineate well the scapulohumeral joint (shoulder joint) revealing possible calcium deposits or other pathology.
External rotation represents a true AP projection. supination of the hand and external rotation of the elbow so that the interepicondylar line is parallel to the IR.
External rotation the greater tubercleis now seen laterally in profile. The lesser tubercle now is located anteriorly, just medial to the greater tubercle
Internal rotation the hand and arm are rotated internally until the epicondyles of the distal humerus are perpendicular to the IR.
AP projection of the shoulder taken in the internal rotation position is therefore a lateral position of the proximal humerus in which the greater tubercle now is rotated around to the anterior and medial aspect of the proximal humerus. lesser is medially
Neutral rotation is appropriate for a trauma patient when rotation of the part is unacceptable. epicondyles appear approx 45 degree angle to the IR. It places the greater tubercle anteriorly but still lateral to the lesser tubercle.

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