Ch. 8 Upper Limb Bones Flashcards
Humerus
- longest and largest bone of the free part of the upper limb
- proximal ball-shaped head articulates with the glenoid cavity of the scapula
- distal end have capitulum (articulate head of radius) and trochlea (articulate with ulna) (flatter; medial and lateral epicondyle: flex wrist and interphalangeal)
- radial fossa and coronoid fossa (flex forearm)
- olecranon fossa (tip of elbow) and radial groove on posterior view
Ulna
- longer of two forearm bones, bigger proximal- smaller distal
- located medial to the radius
- contains:
olecranon- tip of elbow, articulates with olecranon fossa
coronoid process- part of humerus articulates coronoid fossa
trochlear notch- where trochlear of humerus articulates
styloid process- articulates with first 3 carpal bones
head- distal end
ulnar tuberosity
radial notch- articulates with head of radius
Proximal Row of Carpal
scaphoid, lunate, triquetum and pisiform
- schaphoid most commonly fractured
Distal Row of Carpals
trapezium, trapeizoid, capitate, hamate
(She Is Too Pretty)
(Try To Catch Her)
Carpal Tunnel
space between carpal bones and flexor retinaculum
- median nerve passes through carpal tunnel
Appendicular Skeleton
- primary function is movement
- includes bones of the upper and lower limbs
- girdles attach the limbs to the axial skeleton
Capitulum and Radial Fossa
is a rounded knob on the lateral aspect of the humerus that articulates with the head of the radius
anterior depression above the capitulum that articulates with the head of the radius when the forearm is flexed
Trochlea and Cornoid Fossa
located medial to the capitulum that articulates with the ulna
anterior depression that receives the coronoid process of the ulna when forearm is flexed
Radius
- proximal end has head that articulates with the capitulum of the humerus and radial notch of ulna
- neck
- radial tuberosity, attachment of biceps brachii
- styloid process: most common fracture in adults older than 50
Carpals in proximal row (lateral to medial)
scaphoid lunate triquetrum pisiform - articulate with distal end of the ulna nad radius to form the wrist joint
Carpals in Distal Row (lateral to medial)
trapezium
trapezoid
capitate: largest carpal bone, head articulates with lunate
hamate
Metacarpal Bone
proximal base: articulate with distal row of carpal bones to form capometacarpol joints
intermediate shaft
distal head: articulate with the proximal phalanges to form (knuckles) metacarpophalangeal joints
- numbered I-V: thumb to medial
Phalanges
- make up distal region of hand
- 14 phalanges in five digits of each hand
- proximal base, intermediate shaft, and distal head
pollex has two phalanges called proximal and distal phalanges
2-5 have proximal, middle, and distal phalanges - articulate with metacarpal bones
- interphalangeal joints inbetween phalanges
Hinge Joint (elbow)
- between trochlea and trochlear notch and between capitulum and head of radius
- reinforced on medial and lateral side by collateral ligaments
- posterior cushion formed by olecranon bursa
- held in place by annular ligament
- pivot action
Radiocarpal Joint
- three proximal carpal bones: scaphoid, lunate and triquentrum
- interface with the distal surface of the radius to form the wrist joint
- contains ulnar collateral ligament to provide flexion, extension, adduction, adduction, and NO rotation
Metacarpophalangeal and Intercarpol Joints
- condyloid joint and hinge joints
- anterior palmar ligament and two collateral ligaments
- no support posteriorly
Biceps Brachii
- long head: tubercle above glenoid cavity of scapula (supraglenoid tubercle) short head: coracoid process of scapula
- radial tuberosity of radius and bicipital aponeurosis
- flexes forearm at elbow joint, supinates forearm at radioulnar joints, and flexes arm at shoulder joint
- musculocutaneous nerve
Briahialis
- distal, anterior surface of humerus
- ulnar tuberosity and coronoid process of ulna
- flexes forearm at elbow joint
- musculocutaneous and radial nerves
Brachioradialsis
- lateral border of distal end of humerus
- superior to styloid process of radius
- flexes forearm at elbow joint; supinates and pronates forearm at radioulnar joints to neutral position
- radial nerve
Triceps Brachii
Long head: infraglenoid tubercle, a projection inferior to glenoid cavity of scapula
lateral head: post. surface of humerus above radial groove
medial head: entire posterior surface of humerus inferior to a groove for the radial nerve
- olecranon of ulna
- extends forearm at elbow joint and extends arm at shoulder joint
- radial nerve
Anconeus
- lateral epicondyle of humerus
- olecranon and superior portion of shaft of ulna
- extends forearm at elbow joint
- radial nerve
Pronator Teres
- medial epicondyle of humerus and coronoid process of ulna
- midlateral surface of radius
- pronates forearm at radioulnar joints and weakly flexes forearm at elbow joint
- median nerve
Pronator Quadratus
- distal portion of shaft of ulna
- distal portion of shaft of radius
- pronates forearm at radioulnar joint
- median nerve
Supinator
- lateral epicondyle of humerus and ridge near radial notch of ulna
- lateral surface of proximal one-third of radius
- supinates forearm at radioulnar joints
- deep radial nerve