Upper Limb Flashcards
The clavicle develops via both intramembranous & endochondral ossification. The medial growth plate is the last in the body to close – approx 23-25 yrs. Why is that useful to know?
- Help identify the age of the skeleton
- To tell if skeletal growth is complete
Describe the plane of the scapula relative to the frontal (coronal) plane of the body:
30-45 degrees
Describe the position of the scapula relative to the thorax:
a) Root of the spine of scapula
b) Inferior angle
a) 3rd rib
b) 7th rib/ intercostal space
State the attachments of the intra-articular disc.
Inferior attachment =
superior attachment =
inferior = cartilage of 1st costal superior = articular surface of clavicle
What is the function of the intra-articular disc?
To enhance joint curvature and contact and to absorb joint forces
Why is rotation of the clavicle termed conjunct rotation?
conjunct rotation occurs as a results of the tightening of a passive structure. During UL abduction the conoid ligament is tightened and causes clavicular rotation
Explain how the conoid ligament produces upward rotation of the clavicle.
What is the advantage of this?
The conoid ligament attaches to the posterior medial part of the clavicle (conoid tubercle), when tightened, the tubercle is pulled towards the coracoid process of the scapular creating upwards rotation. This is advantageous as upwards rotation of the clavicle allows increased rotation of the scapular and this increased GHJ range of motion, through conjunct rotation
the glenoid labrum
• where does it attach?
• what is it made of?
• what are its functions?
attachment: margin of the glenoid cavity
made of: fibrocartilage
functions: to increase articular surface and absorb joint forces
Which tendon attaches to the supraglenoid tubercle and the superior aspect of the labrum and what is a possible consequence of this?
The tendon of the long head of biceps brachii, as a result is can become impinged during GHJ movement
The inferior glenohumeral ligament complex (IGHLC) – has anterior & posterior bands with a loose axillary pouch between them. Why?
The pouch allows extra range of movement when stretched
The transverse humeral ligament is extra-capsular. What is its function?
To hold the tendon of the long head of biceps brachii in place
Which 2 ligaments provide the main resistance to Inferior translation of the humerus when the upper limb is adducted (relaxed standing)?
coracohumeral ligament and superior glenohumeral ligament
The GHJ is the most mobile and most commonly dislocated joint in the body. Anterior-inferior (subcoracoid) dislocation is by far the most common. Which ligament resists anterior / inferior translation of the humeral head on the glenoid when the upper limb is in a position of 90 degrees abduction + external rotation:
anterior band of the inferior glenohumeral ligament complex
Which structures form the coracoacromial arch?
coracoid process of clavicle, acromion process of scapular and coracoacromial ligament
What is the subacromial space?
The space below the coracoacromial arch, which contains the sub-acromial bursa, supraspinatus and long head of biceps brachii tendon
Name the 3 anatomical joints of the shoulder region involved in achieving full (~180 degrees) UL abduction AND state their relative contribution to that movement (in degrees or fractions).
- GHJ > 120 degrees - 2 thirds
- ACJ > 20 degrees
- SCJ > 40 degrees
ACJ & SCJ make up 1 third
What is meant by medial winging of the scapular?
lifting of the medial boarder of the scapular during dynamic movement due to instability
What could cause medial winging of the scapular?
- Muscle weakness:
- Nerve dysfunction:
- Muscle weakness: serratus anterior
2. Nerve dysfunction: long thoracic n. or C5 to C7 trunk
What muscle does the suprascapular nerve innervate?
supraspinatus
infraspinatus
Define varus alignment
distal end is medial compared to the proximal end
Define valgus alignment
distal end is lateral compared to the proximal end
The normal alignment of the humerus and ulna in the frontal plane is
10-15 degrees valgus
The olecranon process of the ulna is an attachment for?
triceps brachii
The ulnar tuberosity of the ulna is an attachment for?
brachialis
The articular fovea of the head of the radius articulates with?
The captiulum of humerus
The articular circumference of the head of the radius articulates with?
The radial notch of the ulna
Which structures limit elbow flexion?
humeroulnar and humeroradial articulation & muscle bulk
Which structures limit elbow extension?
the olecranon process of the ulna and muscle tension
Which structures limit elbow supination?
IOL tension, the oblique cord & pronators
Which structures limit elbow pronation?
IOL tension, oblique cord and supinators
In elbow extension, what limits valgus?
AMCL + humeral-ulnar articulation
In elbow flexion, what limits valgus?
AMCL > humeral-ulnar articulation
In elbow extension, what limits varus?
humeral-ulnar articulation > LCLC
In elbow flexion, what limits varus?
humeral-ulnar articulation > LCLC
Any muscle involved in supination – pronation must insert onto the:
cubital fossa
Name the 2 primary muscles of supination:
supinator and biceps brachii
Identify the boundaries of the cubital fossa.
medial border of brachioradialis, medial border of pronator teres and the epicondyle line
The main contents of the cubital fossa (from lateral to medial) are the:
- biceps brachii tendon
- brachial artery
- median nerve
- ?
ulnar nerve
Palpate the cubital tunnel behind the medial epicondyle of the humerus. Which nerve travels through here?
ulnar nerve
The humerus has two necks; the anatomical and the surgical, why are they called this?
Anatomical neck is directly below the head of the humerus - anatomical location
Surgical neck is located at a common fracture site that often requires surgery
What movement does the anterior sternoclavicular ligament resist?
Anterior glide of the medial end of clavicle; retraction of clavicle
What movement does the posterior sternoclavicular ligament resist?
Posterior glide of the medial end of clavicle; protraction of clavicle
What movement does the interclavicular ligament resist?
Superior glide of the medial end of clavicle; lateral displacement
What movement does the Intra-articular disc resist?
Medial displacement of the clavicle
What movement does the costoclavicular ligament resist?
Everything except inferior displacement
What movement does the Superior acromioclavicular ligament resist?
all glides of clavicle on acromion
What movement does the Inferior acromioclavicular ligament resist?
all glides of clavicle on acromion
What movement does the Trapezoid ligament resist?
Scapula moving medial relative to clavicle
What movement does the Conoid ligament resist?
Lateral clavicle moving superiorly
suspends the scapula
What movement does the Coracoacromial ligament resist?
If GHJ is very unstable it can resist the superior migration of the HOH
What muscles perform Sternoclavicular / clavicular elevation?
superior fibers of trapezius
What muscles perform Clavicular depression?
Subclavius
What muscles perform Scapular elevation?
superior fibers of trapezius
Levator scapulae
Rhomboid minor
Rhomboid major
What muscles perform Scapular depression?
Lower trapezius +/- pectoralis minor
What muscles perform Scapular abduction / protraction?
Serratus anterior
Pectoralis minor
What muscles perform Scapular adduction / retraction?
Superior, middle + lower trapezius
Levator scapulae
Rhomboid major
Rhomboid minor
What muscles perform Scapular upward rotation?
Superior, middle & lower trapezius
Serratus anterior
What muscles perform Scapular downward rotation?
Levator scapulae
Rhomboid major
Rhomboid minor
What muscles perform Scapular anterior tilt?
Rhomboid major
Rhomboid minor
Levator scapulae
Pectoralis minor
What muscles perform GHJ flexion?
Anterior deltoid Middle deltoid Clavicular head pectoralis major Coracobrachialis Biceps brachii
What muscles perform GHJ Extension?
Sternal head pectoralis major
Latissimus dorsi
Teres major
Posterior deltoid
What muscles perform GHJ Abduction?
Middle deltoid*
Anterior deltoid
Supraspinatus (SST)
What muscles perform GHJ Adduction?
Posterior deltoid
Sternal head pectoralis major
What muscles perform GHJ Internal (medial) rotation?
Subscapularis (SSC)
Anterior deltoid
Pectoralis Major
Latissimus dorsi
What muscles perform GHJ External (lateral) rotation?
Infraspinatus (IST) Teres minor (T min) Posterior deltoid
What muscles perform GHJ Horizontal flexion/ adduction?
Pectoralis major
Anterior deltoid
What muscles perform GHJ Horizontal extension/ abduction?
Posterior deltoid
infraspinatus
What spinal levels make up the Brachial Plexus
C5 - T1
What major nerves are part of the Posterior Cord?
Axillary Radial Upper subscapular Thoracodorsal Lower subscapular
What major nerves are part of the Lateral Cord?
Lateral pectoral
Musculocutaneous
What major nerves are part of the Medial Cord?
Medial pectoral
Ulnar
What major nerve is part of both the medial and lateral cord?
Median
What are the boundaries and contents of the suprascapular foramen?
Boundaries: superior border of scapula, superior transverse scapular ligament
Contains: suprascapular nerve
What are the boundaries and contents of the quadrangular space?
Boundaries: shaft of the humerus laterally, the long head of the triceps medially, the teres minor muscle superiorly, and the teres major muscle inferiorly
Contains: Auxiliary nerve and posterior humeral circumflex artery
What are the boundaries and contents of the triangular interval?
Boundaries: teres major superiorly, the long head of the triceps medially, and the lateral head of the triceps laterally
Contains: Radial nerve and profunda brachii artery
What type of joint is the humeroulnar joint and what is it made up of?
Synovial hinge
Trochlea of humerus & trochlear notch of ulna
What type of joint is the humeroradial joint and what is it made up of?
Synovial hinge
Capitulum of humerus & fovea of radial head
What type of joint is the proximal radioulnar joint and what is it made up of?
Synovial pivot
Radial notch of ulnar & head of radius
What does the articular capsule of the elbow resist?
minimal (lax)
Anterior capsule may resist valgus in Ext.
What does the radial collateral ligament (RCL) of the elbow resist?
varus & posterolateral instability
What does the lateral ulnar collateral ligament (LUCL) resist?
varus
& posterolateral instability
What does the medial collateral ligament (MCL) resist?
valgus force
anterior band
important
What does the annular ligament resist?
Lateral & distal subluxation of the radial head
What does the oblique cord resist?
End range supination
What does the interosseous membrane (ligament) (IOM/IOL) resist?
separation of radius / ulna
What does ‘close-packed position’ of a joint refer to?
The “close-packed position” of a joint is defined as the position of great articular contact & when the capsuloligamentous stabilisers are most taut.
What is the close packed position of the humeroulnar joint?
extension
What is the loose packed position of the humeroulnar joint?
80~ degrees Flexion
In which direction do the fibres of the interosseous ligament run?
From distal radius to proximal ulna
Proximomedially
Describe the axial transmission of force from the wrist to the humerus
When falling on a pronated & flexed wrist with an extended arm (most common), force is first directed at the carpals. This is then received at the radius, the IOM then distributes this force to the ulna as the force moves proximally. Force is then distributed from the olecranon of the ulna to the humerus and up the upper arm
In which range of pronation – supination is there maximal force transmission across the PRUJ & DRUJ?
PRUJ: 0-30 degrees
DRUJ: 0-60 degrees
Supination
What is the significance of force transmission across the PRUJ & DRUJ functionally?
Greatest load transmission across the joints in neutral to 60 degrees supination distally
In which range of pronation – supination is the interosseous membrane lax? What is the significance of this functionally?
Full pronation - Falling on a pronated wrist increases the susceptibility of injury to the radius as the IOM’s ability to distribute force is impaired when it is lax
What are the medial and lateral intermuscular septa?
The lateral intermuscular septum separates the anterior and posterior compartments of the arm whilst the medial septum separates the lateral and medial compartments of the arm
What movement(s) does Biceps brachii (Long and Short head) produce?
Elbow F & forearm sup’n
+ GHJ F
What movement(s) does brachialis produce?
Elbow Flexion
What movement(s) does triceps brachii (long head, lateral head & medial head) produce?
Elbow E (+ GHJ E by long head)
What movement(s) does pronator teres produce?
Elbow flexion
Wrist Pronation
What movement(s) does flexor carpi radialis produce?
Wrist flexion + abduction
What movement(s) does palmaris longus produce?
wrist flexion
What movement(s) does flexor carpi ulnaris produce?
wrist flexion and adduction
What movement(s) does pronator quadratus produce?
wrist pronation
What movement(s) does flexor digitorum superficialis produce?
flex 2nd - 5th digit (PIP joint)
What movement(s) does flexor digitorum profundus produce?
flex 2nd - 5th digit (PIP & DIP joint)
What movement(s) does flexor pollicis longus produce?
flex 1st digit
What movement(s) does brachioradialis produce?
Elbow flexion
What movement(s) does extensor carpi radialis longus produce?
Wrist extension and abduction
What movement(s) does extensor carpi radialis brevis produce?
wrist extension and abduction
What movement(s) does extensor carpi ulnaris produce?
wrist extension and adduction
What movement(s) does supinator produce?
wrist supination
What movement(s) does anconeus produce?
Retracts joint capsule during elbow E.
Abduction of ulna during pronation.
Posterolateral stability
What movement(s) does extensor digitorum produce?
2nd - 5th digit extension
What movement(s) does extensor digiti minimi produce?
5th digit extension
What movement(s) does extensor pollicis brevis produce?
1st digit extension
What movement(s) does extensor pollicis longus produce?
1st digit extension
What movement(s) does abductor pollicis longus produce?
1st digit abduction
What movement(s) does extensor indices produce?
2nd digit extension
Which nerve travels through pronator teres?
Median Nerve
Which nerve travels through supinator?
Radial (deep)
Name the 2 main superficial veins of the upper limb
cephalic and basilic veins
name the vein in the cubital fossa that connects the two main superficial veins of the upper limb
median cubital vein
Which nerve travels deep to brachioradialis
radial nerve
What attaches at the fovea of the distal ulna?
TFCC
What articulates with the articular circumference of the distal ulna?
ulnar notch of the radius
What is the dorsal tubercle of the distal radius a pulley for?
the tendon of extensor pollicus longus
The lunate tends to dislocate in what direction?
volar (Towards flexor surface)
the tubercle of the trapezium is an attachment for?
flexor retinaculum
The hook of the hamate provides attachment for?
flexor retinaculum
the most common carpal bone to fracture is?
scaphoid
the common mechanism of injury to the scaphoid is?
forceful hyperextension where the scaphoid impacts the dorsal rim of the radius
At the radiocarpal joint the radius articulates with?
the lunate and scaphoid
which carpal bone has greater contact with the radius
scaphoid
The TFCC articulates with the?
radius, ulna, lunate, triquetrium
What is the structural classification of the radiocarpal joint?
synovial, ellipsoid
Explain the term “avascular necrosis” and why it is a possible secondary complication post-scaphoid fracture
Avascular necrosis is the death of bone tissue due to a lack of blood supply. It can lead to tiny breaks in the bone and the bone’s eventual collapse. A broken bone or dislocated joint can interrupt the blood flow to a section of bone. Since the scaphoid blood supply comes from two different vascular branches of the radial artery, fractures can limit access to blood supply
The volar aspect of the head of the metacarpal is wider than the dorsal aspect. What is the significance of this?
The dorsal surface, broad and flat, supports the tendons of the extensor muscles.
The volar surface is grooved in the middle line for the passage of the flexor tendons. The wider heads of the metacarpals allow the tendons to sit in the grooves during flexion. All of these features are to increase stability which tightens ligaments, improves grip and restricts abduction
What is the “midcarpal joint”?
A synovial joint between the proximal row (scaphoid, lunate & triquetrum) and distal row (trapezoid, trapezium, capitate & hamate) of carpal bones
Which row of carpals exhibits a greater amount of movement between adjacent carpal bones?
The proximal row - each carpal moves independently
Which row generally moves as a unit? Which bone is most commonly used as the reference in measurement of ROM?
The distal row. The capitate is generally used as a reference
Do you have greater range of flexion or extension at the wrist? Why?
Flexion, bony features and volar tilt
Do you have greater range of abduction or adduction at the wrist? Why?
Adduction, styloid of radius
Compare the mobility of the 1st CMC to the 2nd – 5th CMC joints.
1st > 2nd -5th: saddle joint compared to plane joint
The 2nd metacarpal articulates with the trapezium, trapezoid, capitate & 3rd metacarpal which makes it the least mobile. What is the advantage of this?
It creates a stable column in the center of the hand which allows for force transfer and stablises the 2nd digit when pointing or pushing
Compare the mobility of the 1st MCP to the 2nd – 5th MCP’s.
1st < 2nd -5th
Pinch your thumb & index – what force does it exert on your 1st MCP joint?
Which collateral ligament of the thumb resists this force?
Valgus force
Ulnar collateral ligament of the thumb
Compare the articular surface areas on the metacarpal and phalange in the MCP joints.
What structure improves contact area of this joint?
Palmar plate
Identify the collateral ligaments of the MCP joint. In which position are they taut?
Flexion
What is the transverse carpal ligament / flexor retinaculum function?
To protect the entrance of tendons and nerves into the hand from the wrist
Many muscles of the forearm cross the wrist. Which of these inserts onto the base of the metacarpals?
Flexor carpi radialis Flexor carpi ulnaris Extensor carpi radialis longus Extensor carpi radialis brevis Extensor carpi ulnaris
Give examples of how muscles of the forearm that cross the wrist work together in teams
Flexor carpi radialis and flexor carpi ulnaris work together to flex the wrist
Extensor carpi radialis longus, Extensor carpi radialis brevis and extensor carpi ulnaris work together to extend the wrist. If only the radial or ulnaris muscle(s) was to contract in one of these movements abduction or adduction would occur instead of flexion or extension
Which muscles of the forearm that cross the wrist is best designed to produce wrist extension and why?
extensor carpi radialis brevis, due to its line of action (longus would provide more abduction)
Which muscles of the forearm that cross the wrist produces a varus force on the elbow when it contracts?
extensor carpi ulnaris
Which muscles travel through the carpal tunnel?
Flexor digitorum superficialis
Flexor digitorum profundus
Palmaris longus
What movement(s) does abductor pollicis brevis produce?
Abduction of 1st digit (thumb)
What movement(s) does flexor pollicis brevis produce?
Flexion of 1st digit (thumb)
What movement(s) does opponens pollicis produce?
Opposition of 1st digit (thumb)
What movement(s) does abductor digiti minimi produce?
Abduction of 5th digit
What movement(s) does flexor digiti minimi produce?
Flexion of 5th digit
What movement(s) does opponens digiti minimi produce?
Opposition of 5th digit
What movement(s) does palmaris brevis produce?
improves grip
What movement(s) does adductor pollicis produce?
Adducts the 1st digit (thumb) at the CMC joint
What movement(s) does palmar Interossei produce?
Adduction, flexion and extension
What movement(s) does dorsal Interossei produce?
Abduct fingers
What movement(s) does the lumbricles produce?
Flex MCP joints and extends IP joints
Describe the distal insertion of the extensor digitorum
The extensor digitorum expands into three bands at the MCP. The central band extends to the middle phalanx whilst the lateral bands wrap around the middle phalanx and insert onto the distal phalanx.
What is the extensor hood mechanism? What is its function?
Expansion of the extensor digitorum to provide an attachment for the interossei and lumbricales and allows specialised dorsal grip at the fingers
The ulnar nerve passes superficial to the flexor retinaculum and enters the hand via?
Guyon’s canal
What are the 2 arteries of the forearm (branches of the brachial artery)?
Radial artery
Ulnar artery
which tendon travels around the dorsal tubercle of the radius
extensor pollicis longus
Which muscles form the anatomical snuff box?
- Radial side - abductor pollicis brevis & extensor pollicis brevis
- Ulnar side - extensor pollicis longus
What is palpable in the floor of the snuffbox
- proximal = radial styloid
- middle = scaphoid
- distal = scaphotrapezial joint
Describe the common mechanism of a clavicle fracture? i.e. how do they fall? what causes the bone to break?
Occurs through fall on shoulder or direct shoulder trauma. The middle third is the thinnest part of the clavicle. The medial and lateral thirds are well supported by their ligamentous and muscle attachments. Therefore, the middle third is the weakest and most likely to fracture, as this bends the clavicle over the 1st costal. The costal is stronger and this results in fracture.
In a midshaft clavicle fracture, explain the reason for the inferior and medial movement of the lateral end
The clavicle is acting as a strut for the scapula, so the scapula moves downwards when this strut is broken
What is the common mechanism of ACJ dislocation?
A fall onto the point of the shoulder
There are multiple ligaments that stabilise the ACJ. Which ones usually tear first in a sprain? With increasing force and deformity, which additional ligaments are possibly affected?
Acromioclavicular ligament
Coracoclavicular ligaments (trapezoid and conoid ligaments)
Describe AND explain the anatomical basis for the resultant deformity of an ACJ dislocation. i.e. How does it appear and why?
A superior displacement of the distal (lateral) clavicle. This dislocation/ displacement often damages the structural ligaments holding the clavicle, such as the acromioclavicular ligament. After the trauma of the dislocation and lack of structure holding the clavicle in place, the clavicle is forced superiorly.
Explain why SCJ dislocations are much less common than ACJ joint dislocations
The SCJ is sturdier and least mobile joint of the two as it is a plane joint whilst the SCJ is a saddle joint. Usually an ACJ dislocation would occur before a SCJ one.
Why are posterior SCJ dislocations potentially life threatening?
Posterior to the SCJ are many major blood vessels and the trachea which could be punctured in a posterior SCJ dislocation.
Which passive & active structures provide support to the GHJ in the anatomical position?
Passive = coracohumeral ligament, superior glenohumeral ligament, middle glenohumeral ligament, inferior glenohumeral ligament complex, transverse ligament
Active =supraspinatus, infraspinatus, subscapularis, teres minor
What would be the disadvantage of excessive superior translation of the head of humerus during upper limb abduction?
Impingement of structures in the subacromial space
List 5 muscles that may act to stabilise (or depress) the pectoral girdle when using the upper limbs for weight-bearing purposes such as using crutches or lifting the trunk off a chair:
- Pectoralis major
- Latissimus dorsi
- Pectoralis minor
- Lower traps
- Subclavius
Describe and explain the roles of the deltoid and the rotator cuff muscles during upper limb elevation in the scapular plane.
- Deltoid – upper limb abduction (anterior & middle fibres)
- Rotator cuff (GH head stabilisation)
o Supraspinatus > abduction - The prime mover = middle deltoid
o Largest PCSA & largest moment arm
o In first 80 degrees of abduction > supraspinatus has the largest moment arm but a smaller PCSA - During deltoid and supraspinatus contraction there is superior translation
o This is resisted by infraspinatus and teres major through inferior translation
o To avoid impingement of the subacromial space which contains:
Subacromial bursa – very pain sensitive
Supraspinatus tendon
Long head of biceps tendon
Clavicular features
Ensure that you are able to identify the following bony features AND understand their relevance.
Consider questions such as: Is this feature for attachment or articulation? etc Note any distinguishing features which may assist you in identifying the feature in the future.
From lateral to medial:
- Lateral articular surface
- Trapezoid line
- Conoid tubercle
- Subclavian groove
- Impression for costoclavicular ligament
- Medial articular surface
From lateral to medial:
- Lateral articular surface > articulates with the acromion of scapula
- Trapezoid line > attachment for trapezoid part of coracoclavicular ligament
- Conoid tubercle > attachment for conoid part of coracoclavicular ligament
- Subclavian groove > attachment for subclavian muscle
- Impression for costoclavicular ligament
- Medial articular surface > articulates with manubrium of sternum and 1st costal cartilage
Scapular Features Anterior: Lateral to Medial (Including shared structures): - Acromion - Glenoid cavity - Coracoid process - Infraglenoid tubercle - Lateral border - Suprascapular notch - Subscapular fossa - Superior border - Inferior angle - Superior angle - Medial boarder
Posterior: Lateral to Medial
- Articular surface of acromion
- Greater scapular notch
- Spine of scapula
- Supraspinatus fossa
- Infraspinatus fossa
Anterior: Lateral to Medial (Including shared structures):
- Acromion > attachment for lower trapezius & middle deltoid muscles
- Glenoid cavity > articulates with head of humerus
- Coracoid process > attachment for pectoralis minor & coracobrachialis muscles
- Infraglenoid tubercle > attachment for long head of biceps brachii muscle
- Lateral border > attachment for teres minor muscle
- Suprascapular notch > passage for suprascapular nerve
- Subscapular fossa > attachment for subscapularis muscle
- Superior border > shortest and thinnest border
- Inferior angle > attachment for teres major & part of latissimus dorsi muscles
- Superior angle > attachment for levator scapulae muscle
- Medial boarder > attachment for serratus anterior, levator scapulae, rhomboid major & rhomboid minor muscles
Posterior: Lateral to Medial
- Articular surface of acromion > articulates with lateral end of the clavicle (acromial end)
- Greater scapular notch > connects supraspinous and infraspinous fossas > passageway for suprascapular nerve and suprascapular artery
- Spine of scapula > attachment for levator scapulae, middle & lower trapezius, posterior deltoid & supraspinatus muscles
- Supraspinatus fossa > attachment for supraspinatus muscle
- Infraspinatus fossa > attachment for infraspinatus muscle
Proximal to Distal (Proximal End):
- Head of humerus
- Anatomical neck
- Greater tubercle
- Lesser tubercle
- Intertubercular sulcus
- Surgical neck
- Lateral lip of intertubercular sulcus
- Medial lip of intertubercular sulcus
- Roughening of floor of intertubercular sulcus
- Deltoid tuberosity
- Radial groove
Proximal to Distal (Proximal End):
- Head of humerus > articulates with glenoid cavity of scapula
- Anatomical neck > directly below head of humerus
- Greater tubercle > attachment of supraspinatus (superior facet), infraspinatus (middle facet) & teres minor (inferior facet) muscles
- Lesser tubercle > attachment for subscapularis muscle
- Intertubercular sulcus > passageway for tendon of long head of biceps brachii muscle
- Surgical neck > common fracture site
- Lateral lip of intertubercular sulcus > attachment for pectoralis major muscle
- Medial lip of intertubercular sulcus > attachment for teres major muscle
- Roughening of floor of intertubercular sulcus > attachment for latissimus dorsi muscle
- Deltoid tuberosity > attachment for deltoid muscles
- Radial groove > passageway for radial nerve & deep brachial artery
Humerus: Proximal – Distal (Distal End): Lateral supracondylar ridge Lateral Epicondyle Medial supracondylar ridge Medial epicondyle Coronoid fossa Capitulum Trochlear Olecranon fossa
Humerus: Proximal – Distal (Distal End):
Lateral supracondylar ridge > attachment for brachioradialis, extensor carpi radialis longus and triceps brachii muscles and for the lateral intermuscular septum
Lateral Epicondyle > attachment for common supinator tendon (anconeus, supinator, extensor carpi radialis brevis, extensor digitorum, extensor digiti minimi and extensor carpi ulnaris) and the radial collateral ligament
Medial supracondylar ridge > attachment for brachialis, pronator teres and medial head of triceps brachii muscles and for the medial intramuscular septum
Medial epicondyle > attachment for pronator teres, common flexor tendon (flexor carpi ulnaris, flexor carpi radialis, flexor digitorum superficialis and palmaris longus) and ulnar collateral ligament
Coronoid fossa > articulates with the coronoid process of the ulna
Capitulum > articulates with the articular fovea of the head of the radius
Trochlear > articulates with the trochlear notch of the ulna
Olecranon fossa > articulates with the olecranon of the ulna
Radius: Proximal – Distal Head (articular fovea) Head (articular circumference) Neck Radial tuberosity Supinator crest Oblique line Interosseous border Radial styloid process Ulna notch Dorsal tubercle
Radius: Proximal – Distal
Head (articular fovea) > articulates with the capitulum of the humerus
Head (articular circumference) > articulates with the radial notch of the ulna
Neck > directly below the head of the radius
Radial tuberosity > attachment for biceps brachii tendon
Supinator crest > attachment for supinator muscle and lateral ulnar collateral ligament
Oblique line > attachment for oblique cord
Interosseous border > attachment for interosseus membrane/ ligament
Radial styloid process > attachment for brachioradialis, abductor pollicis longus and extensor pollicis brevis muscles and radial collateral ligament
Ulna notch > articulates with the articular circumference of the head of ulna
Dorsal tubercle > pulley attachment for the tendon of extensor pollicis longus
Ulna: Proximal – Distal Olecranon Coronoid process Trochlear notch Ulnar tuberosity Radial notch Oblique line Interosseous border Ulnar styloid process Head of ulna
Ulna: Proximal – Distal
Olecranon > articulates with the olecranon fossa of the humerus
Coronoid process > articulates with the coronoid fossa of the humerus and attachment for flexor digitorum superficialis, flexor digitorum profundus, pronator teres and flexor pollicis longus muscles
Trochlear notch > articulates with the trochlear of the humerus
Ulnar tuberosity > attachment for brachialis muscle and oblique cord
Radial notch > articulates with the articular circumference of the head of the radius
Oblique line > attachment for oblique cord
Interosseous border > attachment for interosseus membrane/ ligament
Ulnar styloid process > attachment for TFCC
Head of ulna > articulates with ulnar notch of radius