UAMS Department of Neurobiology and Developmental Sciences - Bones of the Upper Limb

Gross Anatomy


Bones of the Upper Limb - Listed in Proximal to Distal Order

Bone Structure Description Notes
clavicle   an "S" shaped bone located between the sternum and the scapula it articulates medially with the manubrium of the sternum and laterally with the acromion process of the scapula; it forms a strut that supports the upper limb; it is frequently fractured; it is the first bone to begin ossification during development
  sternal extremity the thickened proximal end of the clavicle it is triangular in cross-section; it articulates with the clavicular notch of the sternum through a synovial joint with two joint cavities separated by an articular disk; the sternoclavicular joint has the action of a ball and socket joint, but not the physical shape of one
  acromial extremity the flattened lateral end of the clavicle it is marked on its inferior surface at the junction of the medial 2/3 and the lateral 1/3 by a roughened area for attachment of the coracoclavicular ligament; it articulates with the coracoid process of the scapula through a syndesmosis; it articulates with the acromion process of the scapula through a synovial joint; due to the shape of the distal clavicle, the acromion process passes inferior to the clavicle in acromioclavicular dislocations
scapula   the bone of the shoulder the scapula floats in a sea of muscles, so it is difficult to fracture; it articulates with only one bone - the clavicle at the coracoclavicular and acromioclavicular joints
superior border the superior edge of the scapula the superior border of the scapula is marked by the scapular notch laterally
medial border the border of the scapula that runs from the superior angle to the inferior angle it is an important site of muscle attachments for the intermediate layer of back muscles
superior angle the angle of the scapula formed at the union of the superior and medial borders it is the attachment site for the levator scapulae m.
lateral border the portion of the scapula that runs inferomedially from the infraglenoid tubercle to the inferior angle it is an important site of muscle attachments for the teres major m., teres minor m. and the long head of the triceps brachii m.; it has a groove for passage of the circumflex scapular a.
inferior angle the angle of the scapula formed by the union of the medial and lateral borders the inferior angle of the scapula often has a slip of origin of the latissimus dorsi attached to it
glenoid cavity the articular surface located at the junction of the superior and lateral borders of the scapula it articulates with the head of the humerus; it is deepened by a fibrocartilaginous rim called the glenoid labrum
supraglenoid tubercle a projection of bone located superior to the glenoid cavity it is the attachment site for the tendon of the long head of the biceps brachii m.
infraglenoid tubercle a projection of bone located inferior to the glenoid cavity it is the attachment site of the tendon o of the long head of the triceps brachii m.
spine a heavy ridge that runs from the medial border of the scapula to the acromion process it supports the acromion process; it divides the posterior surface of the scapula into a supraspinatous fossa and an infraspinatous fossa
scapular notch a notch on the superior border of the scapula located medial to the attachment of the coracoid process it is bridged by the superior transverse scapular ligament; the suprascapular a. passes superior to the superior transverse scapular ligament and the suprascapular n. passes inferior to it (Army goes over the bridge, Navy goes under the bridge)
coracoid process a beak-like process that projects anteriorly from the lateral end of the superior border of the scapula it is the attachment site for the short head of the biceps brachii m., the coracobrachialis m., the pectoralis minor m. and the coracoacromial and coracoclavicular ligaments
acromion a broad, flat process located at the lateral end of the scapular spine it articulates with the clavicle through a synovial joint (acromioclavicular joint)
supraspinatous fossa a broad depression located superior to the spine of the scapula it is the site of origin of the supraspinatus m.
infraspinatous fossa a broad depression located inferior to the spine of the scapula it is the site of origin of the infraspinatus m.
humerus   the bone of the arm (brachium) the humerus articulates proximally with the scapula at the glenoid fossa; it articulates distally with the radius and ulna at the elbow joint
head the smooth, rounded proximal end of the ulna it articulates with the glenoid cavity of the scapula to form the shoulder joint
anatomical neck the constricted region located inferolateral to the head it is located at the circumference of the smooth articular surface of the head
surgical neck the proximal part of the shaft of the humerus it is located inferior to the greater and lesser tubercles; it is a site of frequent fracture; fractures of the surgical neck of the humerus endanger the axillary n. and the posterior circumflex humeral a.
greater tubercle the large projection located lateral to the head of the humerus it is the attachment site of the supraspinatus, infraspinatus & teres minor mm.
lesser tubercle the projection located lateral to the head of the humerus on the anterior surface it is the insertion site of the subscapularis m.
intertubercular groove the groove on the anterior surface of the humerus that is located between the crest of the greater tubercle and the crest of the lesser tubercle it is occupied by the tendon of the long head of the biceps brachii m.; the transverse humeral ligament spans the intertubercular groove and holds the biceps tendon in place; it is the attachment site for the tendon of the pectoralis major (lateral lip), teres major (medial lip), and latissimus dorsi (floor)
crest of the greater tubercle the ridge of bone on the anterior surface of the humerus extending inferiorly from the greater tubercle it forms the lateral lip of the intertubercular groove; it is the attachment site for the transverse humeral ligament and the pectoralis major m.
crest of the lesser tubercle the ridge of bone on the anterior surface of the humerus extending inferiorly from the lesser tubercle it forms the medial lip of the intertubercular groove; it is the attachment site for the transverse humeral ligament and the teres major m.
deltoid tuberosity the roughened process on the lateral surface of the mid-shaft of the humerus it is the insertion site of the deltoid m.
radial groove the groove that spirals around the posterior surface of the shaft of the humerus it is a depression for the radial n. and the deep brachial vessels; fracture of the humerus at mid-shaft can injure the radial nerve and deep brachial vessels because they are in contact with bone at this location
medial supracondylar ridge a narrow ridge running proximally from the medial epicondyle of the humerus the pronator teres m. takes origin from the common flexor tendon near the most inferior part of the medial supracondylar ridge
lateral supracondylar ridge a narrow ridge running proximally from the lateral epicondyle of the humerus it is the site of origin of the brachioradialis m. and the extensor carpi radialis longus m.
lateral epicondyle a knob-like projection on the lateral side of the humerus proximal to the capitulum it is the site of attachment of the common extensor tendon which is the origin of several forearm extensor muscles (extensor carpi radialis brevis m., extensor digitorum m., extensor digiti minimi m., extensor carpi ulnaris m. and supinator m.); inflammation of the attachment of the common extensor tendon is called lateral epicondylitis which is also known as "tennis elbow"
medial epicondyle a knob-like projection on the medial side of the humerus proximal to the trochlea it is the attachment site of the common flexor tendon which is the origin for the superficial group of forearm flexor muscles (pronator teres m., flexor carpi radialis m., palmaris longus m., flexor carpi ulnaris m. and flexor digitorum superficialis m.); inflammation of the attachment of the common flexor tendon is called medial epicondylitis which is also known as "tennis elbow"; the ulnar nerve is in contact with bone as it courses posterior to the medial epicondyle where it is susceptible to injury from blunt trauma or fracture
coronoid fossa the depression on the anterior surface of the humerus located proximal to the trochlea near the elbow it accommodates the coronoid process of ulna when the elbow is flexed
radial fossa the depression on the anterior surface of the humerus located proximal to the capitulum near the elbow it accommodates the head of the radius when the elbow is flexed
olecranon fossa the depression on the posterior surface of the humerus located just proximal to the elbow it accommodates the olecranon process of the ulna when the elbow is extended
capitulum the rounded process that caps the distal end of the lateral condyle of the humerus it articulates with the head of the radius; capitulum means "little head"
trochlea the grooved process that caps the distal end of the medial condyle of the humerus it articulates with the trochlear notch of the ulna; the shape of the trochlea and the trochlear notch limits side-to-side movement and guarantees a hinge action; trochlea means "pulley"
ulna   the bone on the medial side of the forearm (antebrachium) the ulna articulates proximally with the trochlea of the humerus and the head of the radius; it articulates distally with the ulnar notch of the radius
olecranon the proximal end of the ulna it is the insertion site of the tendon of the triceps brachii m.; when the elbow is extended, the olecranon of the ulna engages the olecranon fossa of the humerus
trochlear notch the crescent shaped notch on the anterior surface of the proximal end of the ulna it is located between the olecranon and the coronoid process; it articulates with the trochlea of the humerus; a ridge within the trochlear notch fits into the groove in the trochlea of the ulna which limits side-to-side movement and guarantees a hinge action
coronoid process the anterior projection of bone located distal to the trochlear notch it is the insertion site of the brachialis m.
radial notch the notch on the lateral surface of the humerus located just distal to the trochlear notch it accommodates the head of the radius; the annular ligament of the radius attaches to the anterior and posterior edges of the radial notch of the ulna to encircle the head of the radius
body the long slender midportion of the ulna it is also called the shaft or diaphysis; the interosseous membrane attaches to the entire length of the interosseous border of the body of the ulna
head the distal end of the ulna it is small and rounded for articulation with the radius
styloid process a small projection from the distal surface of the head of the ulna it is the site of attachment of the articular disk of the distal radioulnar joint
radius   the bone on the lateral side of the forearm (antebrachium) the radius pivots on its long axis and crosses the ulna during pronation
head the rounded proximal end of the radius it has a smooth, rounded surface for articulation with the ulna; the head of the radius is encircled by the annular ligament (4/5 of a circle) and the radial notch of the ulna (1/5 of a circle)
neck the constricted area of the radius located distal to the head the annular ligament of the radius surrounds the head of the radius, not the neck of the radius
radial tuberosity a roughened area on the anteromedial surface of the radius located just distal to the neck it is the insertion site of the tendon of the biceps brachii m.
body the long, slender midportion of the radius it is also known as the shaft or diaphysis; the interosseous membrane attaches to the entire length of the body of the radius along its interosseous border; a fracture of the distal end of the body of the radius with a dorsal displacement of the distal fragment is quite common and is cal a Colles' fracture
ulnar notch a shallow notch located on the medial surface of the distal end of the radius it articulates with the head of the ulna
styloid process the distal-most projection from the lateral side of the radius the radial styloid process projects lateral to the proximal row of carpal bones
carpal bones   the bones of the wrist eight bones arranged in two rows; a pneumonic for memorizing the carpal bones is " some lovers try positions that they can't handle" - the first letters of these eight words are the first letters of the names of the eight carpal bones arranged from lateral to medial, proximal row first: scaphoid, lunate, triquitrum, pisiform/trapezium, trapezoid, capitate, hamate
proximal row lateral to medial: scaphoid, lunate, triquetrum, pisiform the scaphoid and lunate bones of the proximal row articulate with the distal end of the radius
distal row lateral to medial: trapezium, trapezoid, capitate, hamate the distal row of carpal bones articulates with the metacarpal bones of the hand
scaphoid   the most lateral carpal bone of the proximal row the scaphoid bone is located in the floor of the anatomical snuff box; it is frequently fractured by hyperextension and abduction of the wrist; scaphoid means "boat-shaped"
lunate   the carpal bone located between the scaphoid and triquetrum in the proximal row the lunate is so named because it is "moon-shaped" (crescent shaped) in longitudinal section; the head of the capitate sits within the crescent of the lunate
triquetrum   the most medial bone in the proximal row of carpal bones it articulates with the pisiform which sits anterior to it
pisiform   a sesamoid bone in the tendon of the flexor carpi ulnaris m. it articulates with the  um; the pisiform bone provides a protective function for the flexor carpi ulnaris tendon by bearing the forces generated by the tendon riding across the triquitrum, especially during wrist extension; pisiform means "pea-shaped"
trapezium   the most lateral carpal bone of the distal row it forms a saddle joint with the metacarpal bone of the thumb; "the thumb swings on the trapezium"
trapezoid   the carpal bone located between the trapezium and the capitate in the distal row the trapezoid is named for its trapezoid shape
capitate   the carpal bone located between the trapezoid and the hamate in the distal carpal row the capitate is the largest carpal bone; it is named for its rounded head; forces generated in the hand (as during a punching blow with the fist) are transmitted through the third metacarpal bone to the capitate and proximally through the lunate to the radius
hamate   the most medial carpal bone in the distal row the hamulus (hook) of the hamate is its distinguishing characteristic; it is an attachment point of the flexor retinaculum
metacarpal bones   the bones located between the carpal bones and the phalanges of the hand there are a total of five metacarpal bones in the hand; the metacarpals of the four fingers are bound together by ligaments to form a firm foundation for finger movements; the metacarpal of the thumb is more independent in its range of motion
base the proximal end of the metacarpal it articulates with the distal row of carpal bones
body the slender shaft of the metacarpal it is also known as the diaphysis
head the rounded distal end of the metacarpal it articulates with the proximal phalanx of the corresponding digit
phalanx (phalanges)   the distal two or three bones in the digits of the hand there are a total of 14 phalanges in the hand; the thumb has two phalanges (proximal and distal) and each finger has three phalanges (proximal, middle and distal); phalanx means "line of soldiers"
base the proximal end of the phalanx the base of the proximal phalanx articulates with the head of the corresponding metacarpal bone; the base of the middle or distal phalanx articulates with the head of the next most proximal phalanx
body the slender shaft of the phalanx also known as the diaphysis; the body of the distal phalanx is very short
head the distal end of the phalanx the proximal, middle and distal phalanges each have a head; the head of a proximal or middle phalanx articulates with the base of the next most distal phalanx

Some of the material presented in these tables is contained in the book:
MedCharts Anatomy by Thomas R. Gest and Jaye Schlesinger
Published by ILOC, Inc., New York. Copyright 1995.

The content of these tables has been edited for use in this course by Patrick W. Tank, Ph.D.
Copyright 2009, Department of Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences.
Unauthorized use is prohibited.



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