Anatomy of the Elbow Flashcards
(42 cards)
what 3 bones make up the elbow joint?
humerus
radius
ulna
describe the humerus?
largest bone in upper limb long bone expanded laterally (distally); flattened anteroposeriorly; slight curve forward
name the 10 bony landmarks of the humerus (relevant to the elbow)?
capitulum radial fossa coronoid fossa trochlea medial epicondyle lateral epicondyle medial supracondylar ridge lateral supracondylar ridge groove for ulnar nerve olecranon fossa
describe the capitulum?
Articulates with head of radius (meaning its lateral to trochlea)
Convex
Separated from trochlea by a shallow groove
describe the radial fossa?
small shallow depression superior to capitulum
anterolateral (lateral to coronoid fossa)
accommodates head of radius during elbow flexion
describe the coronoid fossa?
small depression found superior to trochlea of humerus
anteromedial (medial to radial fossa)
accommodates head of ulna during elbow flexion
describe the trochlea?
small pulley-shaped projection
inferomedial aspect of condyle of humerus
medial to capitulum
articulates with trochlea notch of ulna (humeroulnar joint formation)
describe the medial epicondyle of the humerus?
Subcutaneous projection found at the distal end of the medial supracondylar ridge of the humerus
More prominent than lateral epicondyle
Contains groove for ulnar nerve
Provides origin site for superficial muscles of anterior compartment of forearm (i.e. common flexor origin)
Attachment site for ulnar collateral ligament
describe the lateral epicondyle of the humerus?
projection found at distal end of lateral supracondylar ridge of humerus
less prominent than medial epicondyle
Provides origin site for superficial muscles of the posterior compartment of the forearm, supinator and anconeus (i.e common extensor origin)
Provides attachment for radial collateral ligament
describe the medial supracondylar ridge of the humerus?
Sharp, prominent margin found along medial aspect of distal end of humerus shaft
Separates anteromedial and posterior surfaces
Provides origin site for pronator teres
describe the lateral supracondylar ridge of the humerus?
Sharp, prominent margin found along lateral aspect of distal end of humerus shaft
Separates anterolateral and posterior surfaces of humerus
Provides origin site for brachioradialis and extensor carpi radialis
describe the groove for ulnar nerve?
shallow depression found on posterior surface of medial epicondyle of the humerus
describe the radius?
long bone
lateral of 2 forearm bones
shorter of 2 forearm bones
head and neck at superior end
name the 4 bony landmarks of the radius (relevant to the elbow)?
dorsal tubercle of radius
head of radius
radial tuberosity
styloid process of radius
describe the dorsal tubercle of radius?
palpable small prominence on posterior aspect of distal end of radius
roughly in line with index finger (between grooves of extensor muscle tendons)
provides attachment for extensor retinaculum and dorsal radiocarpal ligament
describe the head of the radius?
disk shaped expanded area at superior end of bone
2 articular areas: articular circumference (articulates with radial notch of ulna medially/ forms superior radioulnar joint
articular facet (articulates with capitulum of humerus/ forms humeroradial joint)
describe the radial tuberosity?
oval shaped anteromedial aspect of radius at superior end (just inferior to neck)
provides insertion site for biceps brachii
describe the styloid process of radius?
blunt projection found inferomedial aspect of inferior end of bone
provides insertion site for brachioradialis muscle
attachment site for radial collateral ligament of wrist joint+ radioscaphocapiate ligament
easily palpable as sharp and large point on lateral side of wrist
overview of the ulna?
long bone
longer of 2 bones in forearm
medial of 2 bones in forearm
head is distal to the elbow, no neck
what are the 5 bony landmarks of the ulna?
coronoid process
head
olecranon process
styloid process of ulna
ulnar tuberosity
describe the coronoid process?
broad eminence anterosuperior on ulna
superior aspect contains distal portion of trochlea notch
lateral aspect contains radial notch
medial aspect contains sublime tubercle
provides origin for pronator teres, flexor digitorum profundus and the humeroulnar head of flexor digitorum superficialis
insertion site for brachialis
attachment for ulnar collateral ligament
describe the head of the ulna?
distal end of bone
round and expanded
2 articular areas
articular circumference (articulates with ulnar notch
of radius, forming distal radioulnar joint; convex and
smooth
articular facet (attaches to articular disk of distal radioulnar joint; flat area on inferior aspect of ulnar head
describe the olecranon process?
subcutaneous and easily palpable
posterosuperior projection at top of ulna (accommodated by olecranon fossa of humerus during elbow flexion)
anterior aspect contains trochlea notch (accommodated by trochlea of humerus during elbow flexion)
provides origin for ulnar head of flexor carpi ulnaris, insertion for anconeus and triceps brachii tendon, and attachment of ulnar collateral ligament
describe the styloid process of ulna?
subcutaneous, cylindrical projection found posteromedially on inferior end of ulna
provides attachment for ulnar collateral ligament of wrist joint
easily palpable