UE Osteology Flashcards
The upper extremity consists of the shoulder, axillary region, _______ (arm), ___________ (forearm), and ______ (hand)
- brachium (arm)
- antebrachium (forearm)
- manus (hand)
- bone that articulates w/ the manubrium of the sternum and acromion of the scapula
- has a sternal end, body, and acromial end
clavicle

- part of the clavicle
- possesses articular surface for manubrium
- possesses sternal facet which articulates w/ the manubrium at the clavicular notch
- possesses the impression for the costoclavicular L. which is a small depression on inferior surface of clavicle and provides attachment for costoclavicular L. to the 1st rib
sternal end
- part of the clavicle
- possesses the subclavian groove which is on the inferior surface and is an attachment point for subclavius M.
body (shaft)
- part of the clavicle
- possesses the acromial facet which articulates w/ an articular facet on the acromion of the scapula
- possesses the conoid tubercle on the inferior surface, which provides attachment for the conoid L.
- possesses the trapezoid line on the inferior surface which provides attachment for the trapezoid L.
acromial end
Why is the clavicle one of the most fractured bones?
What is an incomplete clavicle fracture called in children?
- clavicle is often fractured due to direct and indirect injuries received by falling
- incomplete clavicle fractures in younger children are referred to as a Greenstick fracture (partial break in the clavicle usually of the superior aspect, gives the appearance of a partially broken stick)

- triangular, flat bone that rests on the posterior thoracic wall
- capable of a good deal of movement at the physiological scapulothoracic joint
- borders: lateral, medial, and superior
- angels: superior, inferior, and lateral
- posterior surface is convex and costal (anterior) surface is concave)
scapula

What are the borders of the scapula and points of importance?
- lateral (axillary) border
- medial (vertebral) border
- superior border: suprascapular notch (transmits suprascapular A. and N.) and coracoid process (anteriorly bent process, provides attachment for numerous muscles and ligaments)

What are the angles of the scapula and points of importance?
- superior (between superior and medial borders)
- inferior (between medial and lateral borders)
- lateral (between superior and lateral borders):
scapular head: glenoid cavity (articular surface for humoral head), supraglenoid tubercle (superior to glenoid cavity, attachment for long head of biceps brachii M.), infraglenoid tubercle (triangular bump, inferior to glenoid cavity, attachment for long head of triceps brachii M.)
scapular neck: slight constriction between scapular head and lateral border

What are the important points of the posterior and costal (anterior) surfaces of the scapula?
Posterior surface:
- scapular spine (bony ridge, stretches transversely across the posterior surface from the medial border to the lateral angle ending in the acromion): acromion (the point of the shoulder, possesses an articular surface for the clavicle) and deltoid tubercle (attachment point for the deltoid M.)
- greater scapular notch: short passage between the lateral border and the lateral attachment point of scapular spine to the posterior surface
- supraspinous fossa: location of supraspinatus M.
- infraspinous fossa: location of infraspinatus M.
Costal (Anterior) surface:
- subscapular fossa: location of subscapularis M.

- bone in the upper extremity
- articulates proximally w/ the glenoid cavity of the scapula and distally w/ the ulna and radius bones
humerus

What are the important points on the proximal end of the humerus?
- humeral head: rounded, smooth surface, articulates w/ glenoid cavity of scapula
- humeral neck: anatomical neck (exists between humeral head and humeral tubercles, analogous to femoral neck) and surgical neck (between proximal end of humerus and shaft, common fracture site)
- greater humeral tubercle: lateral border of the humerus, attachment point for the supraspinatus, infraspinatus, and teres minor M.
- lesser humeral tubercle: projects anteriorly, attachment point for the subscapularis M.
- intertubercular groove: between humeral tubercles, transmits the long head of the biceps brachii T., also provides attachment points for pectoralis major, teres major, and latissimus dorsi M.

Where is the humerus most commonly fractured?
What is the greater tubercle of the humerus also susceptible to in terms of injury?
- most common fracture site of humerus: surgical neck
- greater tubercle also susceptible to avulsion by supraspinatus, infraspinatus, and teres minor Ms. that insert there

What are the important points on the body (shaft) of the humerus?
- deltoid tuberosity: insertion point for the deltoid M.
- groove for the radial N.: transmits the radial N. and deep brachial A. (according to Olinger this is not easily visible on most bones)

What are the important points on the distal end of the humerus?
- medial and lateral supracondylar ridges: transition point between body and the widened distal end
- lateral humeral epicondyle: common origin for several antebrachial extensors
- medial humeral epicondyle: common origin for several antebrachial flexors; also possesses groove for ulnar N.
- humeral condyle: arrangement of articular surfaces and depressions for the articulation w/ the ulna and radius Bs.; articular surfaces (trochlea and capitulum), anterior depressions (radial fossa and coronoid fossa), and posterior depression (olecranon fossa)

What are the important points of the humeral condyle of the humerus?
- articular surfaces: trochlea (articulates w/ the trochlear notch of the proximal ulna) and capitulum (smooth, rounded process, articulates w/ concave radial head)
- anterior depressions: radial fossa (accommodates the radial head when the antebrachium is flexed) and coronoid fossa (coronoid process of the ulna when the antebrachium is flexed)
- posterior depression: olecranon fossa (accommodates the olecranon of the ulna when the antebrachium is extended)

What is the origin of the expression “funny bone” when hitting the medial portion of the humeral epicondyle on a hard object?
- the origin of this expression is related to the presence of the ulnar N. in the groove for the ulnar N. on the humerus (humerous = funny)
- when the ulnar N. is compressed within the groove, it becomes painful

Severe abduction of the extended elbow, an abnormal movement at this joint, can result in avulsion of the:
medial humeral epicondyle

- bone in forearm
- medial of the two antebrachial bones, articulates w/ the humerus and radius proximally and radius distally
ulna

What are the important points of the proximal end of the ulna?
(larger than the distal end)
- olecranon: provides level for extension of the antebrachium, point of the elbow
- coronoid process (projects anteriorly): radial notch (lateral, smooth notch, articulates w/ the radial head)
- trochlear notch: formed by the olecranon and coronoid processes, grips the humeral trochlea
- ulnar tuberosity: anterior, distal to the coronoid process, attachment point for the brachialis M.
- supinator crest: lateral aspect, distal to the radial notch, attachment point for the supinator M.

- often referred to as “fractured elbow”
- common in cases of falling
- because of the forceful nature of the triceps brachii M., this is considered an avulsion fracture and is difficult to repair
olecranon fracture

- part of the ulna
- relatively smaller than the proximal end
- possesses articular surface for articular disc and the ulnar styloid process
- does not reach the carpus
ulnar head (distal end)

- bone in the forearm
- lateral of the two antebrachial bones
- always on the thumb side
- articulates w/ the humerus and ulna proximally and the ulna and proximal row of carpal bones distally
radius

What are the important points of the proximal end of the radius?
(smaller than the distal end)
- radial head (proximal, disc shaped, concave superior proximal surface): posseses the fovea of the radial head (smooth pit, articulates w/ capitulum of the humeral condyle)
- radial neck (slight constriction distal to the radial head): possesses the radial tuberosity (separates proximal end from body, attachment point for the biceps brachii T.)

















