Upper Limb Flashcards
What is the biggest organ in the body?
How much body weight does it take up?
Skin
16% of body weight
What is the upper limb designed for
Prehension (gripping)
How is the upper limb connected to the axial skeleton
The pectoral girdle
What are the 3 anatomical spaces in the upper limb through which important structures pass
Axilla
Cubital fossa
Carpal tunnel
What are the 9 joints in the upper limb
1) Sternoclavicular and acromioclavicular
2) glenohumeral (shoulder)
3) elbow
4) radioulnar (proximal, middle and distal)
5) radiocarpal (wrist)
6) intercarpal
7) carpometacarpal
8) metacarpophalangeal
9) interphalangeal
Where does the clavicle articulate
With the scapula at the acromioclavicular joint and with the sternum at the sternoclavicular joint
What kind of joint is the glenohumeral joint
Synovial ball and socket
What kind of joint is the elbow joint
How does its stability compare to that of the shoulder joint
Synovial Hinge
Elbow is more stable
What kind of joint is the wrist
What bones are involved
A synovial ellipsoid
A joint between the distal radius and the scaphoid and lunate
Which joint allows the thumb to be fully opposable
An independent saddle shaped joint between the trapezium and the base of the 1st metacarpal
Which muscles attach the pectoral girdle to the axial skeleton (7)
Pectoralis major and minor Trapezius Rhomboid major and minor Latissimus Dorsi Serratus anterior
Which muscles connect the upper limb to the pectoral girdle
Deltoid
Rotator cuff muscles
Biceps
Long head of triceps
What divides the compartments of the arm
Medical and lateral intermuscular septa
Which nerve supplies the anterior compartment of the arm
What about the posterior?
Musculocutaneous
Radial nerve
Which 2 nerves supply the anterior compartment of the forearm
What about the posterior
Median and ulnar
Radial
Which compartment of the arm is bulkier and why
Flexor (anterior)
for the necessary power of gripping
What forms the brachial plexus
The anterior primary rami of C5 to C8 and T1
Which arty supplies the upper limb
The subclavian which becomes the axillary artery at the outer border of the first rib and eventually is continuous with the brachial artery
What are the 2 main superficial veins of the upper limb
Where do they arise from
Where do they connect
Cephalic (on the radial side) and basilic (on the ulnar side)
They arise from the dorsal venous arch of the Hand
The medial cubital vein
What does the lymphatic drainage of the arm follow
Follows the arteries for deep structures and veins for superficial structures
Describe the course of the cephalic and basilic veins
Cephalic: from the dorsal venous arch of the hand it runs along the radial side towards the shoulder where is lies in the deltopectoral groove
It then pierces the clavipectoral fascia you join the axillary vein
Basilic: from dorsal venous arch it runs on ulnar side. It pierced the deep fascia in the mid-arm and joins the venae comitantes og the brachial artery for form the axillary vein
What is the epidermis
A physical and chemical barrier between the body and the exterior
What are the 4 layers of the epidermis from deep to superficial
Stratum basale (basal) Stratum spinosum (spinous ) Stratum granulosum (granular cell layer) Stratum Corneum (horny layer)
Tell me about the stratum basale
A single layer of cells which continually divide, forming new cells and replacing those that are shed from the skin surface.
Melanocytes, which produce melanin, are located in this layer
Describe the stratum spinosum
The thickest layer with prickle cells which are linked by numerous processes
Describe Stratum granulosum
The granular cell layer
Cells here accumulate keratohyalin granules which eventually overfill the cells, destroying nuclei and organelles
Describe the stratum corneum
The horny layer of epidermis
thickest in the palms and soles Contains dead keratinocytes or squames which are continually shed from the surface
What is the extra layer of the epidermis that is present in the hands and feet
Where does it appear
What do its cells contain
Stratum lucidum
Deep to the stratum corneum
Tonofibrils
What are tonofibrils
Densely packed keratin filaments found in the stratum Lucidum
How does the epidermis adhere to the dermis
What is this called
By the interlocking of its downward projections (the epidermal pegs/ ridges) with upward projections of the dermis (dermal papillae)
This is referred to as the dermoepidermal junction
What does the dermoepidermal junction allow
Allows skin to withstand abrasive forces
Without this the layers would move apart, forming a blister
Describe the dermis’ function (3)
Supports epidermis structurally and nutritionally
Its collagen and elastic fibres provide strength to the skin
It is vital for the survival of the epidermis
Where is the dermis thin?
Where is it thin?
What happens with age?
Thin on eyelids
Thick on back
Thins and loses its elasticity with age
Describe the structure of the layers of the dermis
Composed of 2 layers: a thin papillary layer and a thicker reticular layer
What do nails do
Why is most of the nail bed pink?
Provide a firm base for the pulp of the digit
Due to underlying capillaries supplying the dermis
Discuss the different types of sweat glands
Eccrine: control body temperature and are controlled by sympathetic nerves
Apocrine: only present in axilla, mammoth areola and anogenital regions
Sebaceous: present throughout the skin, except palms and soles. These produce sebum which provides a protective covering for the skin
What mediates thermoregulatory blood supply to the skin
Arteriovenous anastomoses
What is responsible for light touch reception
Where are concentrated?
Meissner’s corpuscles
In sensitive areas eg fingers and lips
What are Pacinian corpuscles
Sensitive to vibration and pressure
Which sex has thicker superficial fascia
What is superficial Fascia
Women
Loose connective tissue and subcutaneous fat
Where is fat absent from the superficial fascia
Eyelids
Scrotum
Penis
What is deep fascia composed of
Collagen fibres arranged to respond to lines of stress
Name 1 benefit of fascial compartments
Limiting spread of infection
Describe a first degree burn
A superficial burn where the epidermis is damaged but intact
Describe a second degree burn
Also called a partial thickness burn
It extends through to the dermis
Blisters are the first sign of a second degree burn
As the epidermis cannot perform its function, victims may lose heat, fluid and the ability to combat infections
What is a 3rd degree burn
A full thickness burn
Involves the destruction of both epidermis and dermis
How is surface area calculated
Using the rule of nines
Body = 11 sections
Each section is covered by 9% of total area of skin with genitals as the remaining 1%
What are the 11 sections of the body for the rule of 9
What is the remainder
1. Head 2 and 3. Upper right and left limbs 4. Chest 5. Abdomen 6. Upper back 7. Lower back 8 and 9. Right and left thighs 10 and 11. Right and left legs
Genitals account for remainder of skin
How do blisters occur
Separation of dermis and epidermis, typically due to prolonged friction, leads to fluid moving between the layers
What are Langer’s lines
Who are they particularly important for
Tension/ cleavage lines
Follow orientation of collagen fibres
Surgeons: incisions are made parallel to these lines heal faster and leave neater scars
What in the skin accounts for some of the visual signs of aging
The flattening of the dermoepidermal junction
Loss of elastin causes skin to become loose and lined
What is the best vein in the arm for cannulation
What about for venipuncture
Cephalic - it is large and has a constant position
Median cubital vein
How is the arm divided into compartments
By medial and literal intramuscular septa from the deep fascia that merge with the periosteum of the humerus
What are the 3 muscles of the anterior compartment of the arm
Biceps
Brachialis
Coracobrachialis
What runs in the spiral groove of the humerus
Radial nerve
Profunda brachii artery
What forms the base of the triangle of the medial cubital fossa
What forms its sides
What is the roof and floor
A line joining the humeral epicondyles
Pronator teres and brachioradialis
Roof: deep fascia of forearm
Floor: brachialis and supinator
The long head of biceps originates from the supraglenoid tubercle, how does it then emerge
In a sleeve of synovial tissue in the bicipital groove
Does the musculocutaneous nerve pass superficial to biceps?
Musculocutaneous passes deep to biceps and superficial to brachialis
Does biceps affect the shoulder?
Yes it stabilises the humeral head at the shoulder joint
Name a vein and a nerve that pass superficial to the bicipital aponeurosis and an artery and nerve that lie deep to it
Superficial: basilic vein and medial cutaneous nerve of the forearm
Deep: brachial artery and median nerve
What is the main flexor of the elbow?
Where does it insert?
Brachialis
Coronoid process
From Which cord does the musculocutaneous nerve arise
Which muscle does it perforate
How does it then proceed
Lateral cord
Coracobrachialis
It runs down the lateral side between biceps and brachialis. Just above the elbow it becomes cutaneous as the lateral cutaneous nerve of the forearm
How is the median nerve formed
Which artery does it run with? Until when?
From two heads from the medial and lateral cords of the brachial plexus
Brachial artery until midway along the arm where it crosses anterior to the brachial artery to lie medial to it
What branches does the median nerve give in the arm
None
Name the 3 nerves that arise from the medial cord of the brachial plexus
Ulnar
Medial cutaneous nerve of arm and of forearm
Describe the course of the medial cutaneous nerve of the arm
Arises from the medial cord
Pierces the deep fascia in the superior arm to supply medial and anterior aspects of skin
Describe the course of the ulnar nerve in the arm
Arises from medial cord
Passes down medial side of the axillary and brachial arteries to the mid-arm, then inclines posteriorly to pierce the medial inter muscular septum and passes down to the groove between the olecranon and medial epicondyle
How many branches does the ulnar nerve give in the arm
None
Where does the brachial artery extend from
Lower border of teres major to just distal of the elbow
What is the course of the brachial artery
Proximally runs next to ulnar nerve , on the medial border of coracobrachialis and biceps
As it reaches the elbow, it runs deep to the bicipital aponeurosis, with the medial nerve lying medially
It ends by dividing into the radial and ulnar arteries
What are the branches of the brachial artery in the arm
Profunda brachii
Nutrient branches to humerus
Superior and inferior ulnar collateral branch
Branches to anterior compartment muscles
What are the deep veins of the arm
Venae comitantes
Paired veins that accompany main arteries
What forms the brachial vein
The radial and ulnar veins
When does the axillary vein form
At the lower border of teres major
Which head of triceps is deepest
Medial
How do the nerves and arteries run in relation to the heads of triceps
Radial nerve and profunda brachii run between medial and lateral heads
How many branches are given off from the radial nerve?
3 muscular and 3 cutaneous
They are characteristically given off very proximally to the innervated part
What are the cutaneous branches of the radial nerve
Posterior cutaneous and lower lateral cutaneous of arm
Posterior cutaneous nerve of forearm
What is the most common biceps rupture
What is a key sign of this injury
How is function affected
Rupture if the proximal biceps tendon accounts for >90%
Almost exclusively involves the long head
Popeye muscle: the retracted muscle bunches up leading to a bulge
Minimal functional loss is minimal as the short head is intact
When is biceps tendon rupture most commonly seen
In 40-60 year olds with a history of shoulder problems, secondary to wear and tear of the shoulder
Can be seen in younger individuals during heavy weightlifting or in a fall/ sports accident etc
What can a humeral shaft fracture lead to
What sign can be seen
How do most people recover
radial nerve injury
Wrist drop (extensors not innervated)
Spontaneously
When are supracondylar fractures of the humerus most common
What complications are associated
When would this be a surgical emergency
Childhood (caused by a fall with outstretched hands)
Damage to brachial artery and medial nerve (these structures lie anteriorly)
A pulse less hand resulting from artery compression
What is the most common dislocation in childhood
What is the most common form of dislocation
Elbow (shoulder is most common in adults)
Posterior dislocation of elbow
Which arteries form the superficial and Deep palmar arches
Radial forms deep
Ulnar superficial
Which muscle does the ulnar nerve run through
What does it divide into
Between the 2 heads of flexor carpi ulnaris
The superficial and deep palmar branches in the hand
Which muscle has a function that doesn’t fit with the rest of the posterior compartment
Brachioradialis - it is not a wrist extensor or supinator but instead flexes the elbow with the forearm in a mid prone position
Which superficial wrist extensor muscles don’t extend from the common extensor origin
Brachioradialis
Extensor carpi radialis longus
Where is the common extensor origin
Lateral epicondyle
Where does the extensor retinaculum extend from
Therefore?
The distal radius to the pisiform and triquetral
It is unaffected by pronation and supination
Which wrist flexors arise from the common flexor origin
Superficial layer muscles
Which muscle’s 2 heads does the median nerve pass between
Pronator teres
Where does flexor carpi radialis insert
What is unusual about this
Which muscles does it work with the to abduct the wrist
2nd and 3rd metacarpals
Its tendon does not run in the carpal tunnel - it is in a separate compartment, lying in the groove of the trapezium
Radial extensors
Where does palmaris longus insert?
How does this match its function?
Inserts onto palmar aponeurosis
As well as flexing the wrist, it also tenses the palmar fascia
Which ligaments is the flexor carpi ulnaris associated with
The pisohamate and pisometacarpal ligaments
What is decussation
Which muscle is associated with it in the forearm
What does it allow
Tendons divide into 2 slips which then insert into radial and ulnar aspects of the base of the middle phalanx
Flexor digitorum superficialis
Allows the tendon of flexor digitorum profundus to pass through
Does the FDS flex the elbow
Yes weakly
What is the primary and secondary actions of the flexor digitorum profundus
Primary: flexion of distal interphalangeal joints
Secondary: flexion of proximal interphalangeal, metacarpophalangeal, and wrist joints
Does flexor pollicis longus pass through the carpal tunnel
Yes
How do the fibres of pronator quadratus run
From medial to lateral
What does anconeus do
Extends elbow and pulls ulna posterolaterally
Does the extensor digitorum communis only extend finger joints
No it also contributes to wrist extension as it crosses the wrist
What happens to the tendons of extensor digitorum communis along the fingers
As it crosses the metacarpophalangeal joint it forms an expansion which covers the dorsal side of the proximal phalanx
Over the proximal interphalangeal joint the tendon divides into 3 slips
The middle slip attaches to the middle phalange while the outer 2 extend to the distal phalanx
When is supinator the prime mover for supination
When is supinator weakest
In a fully extended elbow
In a fully flexed elbow
What is the extensor property of the extensor pollicis brevis
Extends thumb at both metacarpophalangeal and carpometacarpal joints
IT DOES NOT EXTEND INTERPHALANGEAL JOINT OF THUMB
Which tendon winds around Lister’s tubercle (dorsal tubercle)
Extensor pollicis longus
What causes carpal tunnel syndrome
What do patients present with
How is it treated
Nerve entrapment caused by compressed median nerve within carpal tunnel
Pain/ paraesthesia in distribution of median nerve and a weakened thenar eminence
Splints to prevent wrist flexion, steroid injections and ultimately surgery to divide flexor retinaculum
What muscle can fractures of distal radius affect
What is sign
Can rupture tendon of extensor pollicis longus due to association with dorsal tubercle
Unable to extend the interphalangeal joint of thumb
What is De Quervain’s disease
What do they present with
How can it be treated
What is another name
Thickening of synovial tendon sheaths of 2 tendons to the thumb (abductor pollicis longus and extensor pollicis brevis)
Pain, tenderness and swelling as well as a difficultly gripping
May be an overuse injury
Surgery can provide relief but there is a risk of injury to sensory branches of radial nerve
De Quervain’s tenosynovitis
What is mallet finger
What is it indicative of
An inablikith to extend the distal interphalangeal joint
An injury to the insertion of the extensor digitorum communis tendon at the base of the distal phalanx
When is mallet finger common
How is it treated
Common sports injury, sustained when there is forced hyperflexion of the distal interphalangeal joint
Splinting DIP joint in slight hypertension
How are patients in A and E with snuffbox tenderness treated
Treated as a scaphoid fracture
By applying plaster cast and X Raying after 4 weeks
What is tennis elbow
Presentation and cause
Treatment
Lateral epicondylitis
Presents with pain over common extensor origin
Resisted wrist extension aggravates pain
Caused by overuse leading to degenerative tear
Rest and steroid injections
What is golfer’s elbow
Presentation and cause
Treatment
Medial epicondylitis
Inflammation of common flexor origin
Presents with Pain over this region
Caused by overuse leading to degenerative tear
Rest and steroid injections
True or false
Breast lymphatic drainage is to the axilla only
False there are also internal thoracic channels
The brachial plexus supplies the whole upper limb. What are the 2 expectations?
Trapezius is supplied by the spinal accessory nerve
Skin on the medial arm is supplied by the intercostobrachial nerve from T2
What is the breast divided into
Lobules
What is the axilla bound by
What does it communicate with superiorly
The anterior and posterior axillary folds
The posterior triangle of the neck
What forms the floor of the axilla
Deep fascia, subcutaneous tissue and skim
What forms the walls of the axilla
Anterior: pec major and minor, subclavius and clavipectoral fascia
Posterior: subscapularis, teres major, and the tendon of latissimus dorsi
Medial: serratus anterior
Lateral: bicipital groove of humerus
What does the axillary artery branch into in the axilla
Subscapular
Anterior and posterior circumflex humeral arteries (these anastomose around the surgical neck of humerus)
How does the axillary vein receive the cephalic vein
As the cephalic pierces the clavipectoral fascia
Where are the trunks of the brachial plexus
Where are the divisions
Posterior triangle of neck
Apex of axilla
What does the axillary nerve supply
Teres minor and deltoid
Where does the palmar cutaneous branch of the ulnar nerve arise
Mid forearm
What does the superficial terminal branch of the ulnar supply
What about the deep terminal branch
Palmaris brevis and the skin of the ulnar fingers
Supplies muscles of hypothenar eminence, all interossei and 2 ulnar lumbricals. It also supplies adductor pollicis
What are the muscles of the hypothenar eminence
Flexor digiti minimi
Abductor digiti minimi
Opponens digiti minimi
When does the median nerve give off the cutaneous supply to the thenar eminence
What is this branch called
Which branch supplies the thenar muscles
Before the carpal tunnel
Palmar cutaneous branch
Recurrent muscular branch
What are the thenar muscles
Flexor pollicis brevis
Abductor pollicis brevis
Opponens pollicis
When does the anterior interosseus branch arise from the median nerve
After it has pierced pronator teres
How does the superficial branch of the radial nerve lie
It eventually divides into the terminal digital branches. Which part of the finger skin doesn’t it innervate
Deep to brachioradialis and lateral to the radial artery
Not beyond the distal phalanges
How are the glandular elements of the breast arranged
Into 15-20 lobules each opening independently onto the surface of the nipple
What is the interlobular tissue in the breast like
Lax to allow expansion during pregnancy
What does the breast connect to
Where is it usually attached
The deep fascia overlying pec major
Between the second and sixth ribs from the lateral sternal edge to the mid axilla
What is the axillary tail
An extension of breast tissue into the axilla
Where is the nipple in the adult Male and young adult female
4th intercostal space
What innervates the breast
What about the nipple
Why is sensory innervation particularly important in the nipple
4th to 6th intercostal nerves
The 4th intercostal nerve
For the suckling reflex
What controls secretion from the breast
Hormones
Where does the blood supply to the breast come from
What about lymph
Axillary, intercostal and internal thoracic arteries with venous drainage from the associated veins
Follows the veins and 75% of lymphatic drainage goes to the axillary nodes
Describe the organisation of the axillary nodes
20-30 nodes
Anterior (pectoral) and posterior (subscapular) and lateral groups drain into the central nodes in the axillary fat
Lymph then drains to the apical nodes
Where are the apical axillary nodes
Where do these drain into
At the apex of the axilla at the lateral border of the first rib
Subclavian lymph trunk which drains into the thoracic duct on the left or the right lymphatic duct on the right
What causes Erb’s palsy
Which spinal roots
What can cause this injury
Injury to the upper trunk of the brachial plexus
(C5 and 6)
Excessive downward traction on the upper limb during a delivery or motorcycle accident etc
What causes the waiter’s tip sign
Arm hangs by the side with a pronated forearm and palm facing posteriorly
What causes Klumpke’s palsy
What can cause this injury
What signs can be seen
Injury to lower fibres of brachial plexus (T1)
Hyper abduction of the shoulder eg in a breech delivery or grasping an object while falling
Wasting of intrinsic muscles of hand
What are the additional symptoms of a proximal nerve lesion compared to a distal one
Inability to flex index and middle fingers and distal phalanx of thumb
Wasting of thenar eminence
Inability to oppose and abduct the thumb with impairment of precision grip
Ulnar deviation at wrist
What is the characteristic sign of a distal nerve lesion
What causes this position
Claw hand
Extended metacarpophalangeal joints and flexed interphalangeal joints of ring and little fingers
Paralysis of interossei and lumbricals (other fingers unaffected as they are median nerve innervated)
What is the ulnar paradox
A proximal ulnar nerve lesion at/ above elbow shows less deformity but functional disability is greater
Why is there less deformity in a proximal ulnar nerve lesion
Ulnar branches to flexor digitorum profundus are also lost
What do radial nerve injuries present with
Wrist drop and weakness of the power grip
What does wrist drop with loss of active elbow extension suggest
Give an example of such a palsy
A proximal radial nerve injury (eg in axilla)
Saturday night palsy - when a drunk person has fallen asleep with their arm across the back of a chair
What is gynaecomastia?
What can cause it!
A benign increase in the size of breasts in males
Hormonal changes usually
Rarely testicular tumours can cause it by secreting β-HCG
How can β - HCG be detected
What does it stand for
Urine pregnancy test
Human chorionic gonadotropin
What is the commonest cancer in women in the UK and world wide
Breast (for both)
How is the type and extent of treatment determined for breast cancer
Biopsy of the sentinel node (the first lymph node draining the cancer)
What is axillary clearance
What can it result in
Removal of axillary nodes
Injury to the long thoracic nerve leading to paralysis of serratus anterior
Can also cause lymphedema, especially if combined with radiotherapy
What does paralysis of serratus anterior lead to
Weakness it should abduction due to loss of scapular rotation
Also leads to winged scapular
What are the 2 anatomic joints of the pectoral girdle
Name any other joints
What do these aid
Sternoclavicular
Acromioclavicular
Scapulothoracic articulation - a physiological joint
These all aid the movement of the glenohumeral joint and contribute greatly to motility of the shoulder
Describe what he Sternoclavicular joint
Synovial joint
Between medial end of clavicle and clavicular notch of manubrium and 1st costal cartilage
Contains a fibrocartilaginous intra-articular disc dividing joint into 2 separate synovial cavities
How does elevation and depression of the pectoral girdle affect the Sternoclavicular joint
What about protraction/ retraction
It involves a rocking motion of the medial end of the clavicle on the fibrocartilaginous disc
A rocking motion of the medial end of the clavicle and the disc together on the manubrium
Describe the acromioclavicular joint
Small synovial joint
Allows a Small degree of motion about 3 potential axes
What is movement of the acromioclavicular joint around the mediolateral axis called
When is this movement important
Rotation
During normal elevation of the upper limb
How much does the rotation of the acromioclavicular joint account for of the glenoid up rotation of the scapula relative to the chest wall
Half
How does the size of the humeral head compare to that of the glenoid fossa
How does the fossa provide extra stability
Humerus is 3x bigger
Its margins are extended by a fibrocartilaginous labrum
How does the capsule of the glenoid fossa attach to the humerus
At the margins of the anatomical neck
Why is the capsule of the shoulder lax inferiorly
To allow abduction
Which ligaments strengthen the glenohumeral joint
Coracohumeral
3 anterior glenohumeral ligaments
What are the 3 planes of movement of the glenohumeral joint
Flexion/ extension
Ad/abduction
Medial/ lateral rotation
What is circumduction
Combination of flexion, extension , abduction and adduction resulting in a circular movement
What are the prime movers of the glenohumeral joint (5)
Deltoid Pec major Latissimus dorsi Teres major Coracobrachialis
What are the rotator cuff muscles
What do they do
Supraspinatus
Infraspinatus
Teres minor
Subscapularis
Hold the humeral head within the glenoid giving strength and dynamic stability
How is abduction performed at the glenohumeral joint
Initiated by supraspinatus
Continued by lateral fibres of deltoid
What is the only true adductor of the shoulder
However…?
Coracobrachialis
Pec major, latissimus dorsi and teres major can also adduct an abducted shoulder
Which muscles rotate the shoulder laterally
Infraspinatus
Teres minor
Which muscles rotate the shoulder medially
Subscapularis
Teres major
Latissimus dorsi and pec major
What kind of muscle is deltoid
Multipennate
What is the origin of deltoid
From the spine of the scapula, acromion and clavicle
How does deltoid attach the the scapula compares to the acromion and clavicle
Scapula: aponeurosis
Acromion and lateral 1/3 of clavicle: fleshy
What is the V shaped tuberosity in the clavicle
Deltoid tuberosity
What do the lateral fibres of deltoid do
What about the anterior fibres
Posterior?
What is its innervation
Lateral: abduction of shoulder
Anterior: medial rotation and flexion
Posterior: lateral rotation and extension
Axillary nerve
How many degrees of internal rotation does scapulothoracic motion provide
What does coordination with the glenohumeral joint allow
What is this called
15 degrees
Coordination allows an increase beyond the initial 120 degrees provided by glenohumeral joint
Scapulothoracic rhythm
Can scapulothoracic movement next independent of the upper limb
Yes
Eg shrugging
Why is the scapula required to move in flexion or abduction of the shoulder
Scapula must elevate and rotate so the glenoid fossa faces more superiorly
Where do the rhomboids arise from
Which direct do the fibres pass
The inferior aspect of the ligamentum nuchae and spines of upper thoracic vertebrae
Inferolaterally to reach vertebral border of scapula
What innervates the rhomboids
What are the highest visible fibres of the muscles
Dorsal scapula nerve
Rhomboid Minor but the bulk of the sheet is major
From where does levator scapulae arise
Where does it insert
What is the innervation
C1-4
Along vertebral border of scapula from superior angle to root of its spine
3rd and 4th cervical anterior rami and dorsal scapula nerve
What is the origin of serratus anterior
Insertion?
Innervation?
Outer surfaces of upper 8/9 ribs
Digitations from ribs 1 and 2 Insert onto central surface of scapula from superior angle to near inferior angle
The rest insert onto the ventral surface of inferior angle
Long thoracic nerve
True or false
Pec minor is a true muscle of the upper limb
True
What is the innervation of pec minor
Origin
Insertion
Medial pectoral nerve from brachial plexus
Ribs 3,4,5 near their Costochondral junctions
Fibres pass superlaterally and converge on a tendon attaching to medial lip of coracoid crest
Does pec minor affect the scapula
Yes
Pulls scapula inferomedially
Pec major
Origin
Insertion
Innervation
Clavicular head: medial half of clavicle
Sternocostal head: sternum, upper 6 costal cartilages, external oblique aponeurosis
Inserts onto lateral lip of bicipital groove
Clavicular head is Innervated by lateral pectoral nerve and sternocostal head by medial pectoral nerve
Function of pec major
Adduct and medially rotate arm
Clavicular head is also major flexor of arm
When can pec major assist in physiology
With the upper limb fixes in abduction, pec major is an accessory muscle of respiration
Where does latissimus dorsi arise
Insertion?
Posterior Iliac crest and via an aponeurosis from vertebral spines inferior to T6
Tendon undergoes 180 degree twist and inserts onto floor of bicipital groove
What does the twist of latissimus dorsi tendon mean
Illiac fibres insert proximal to fibres from thorax
Innervation of latissimus dorsi
Thoracidorsal nerve
What kind of joint is formed between the inferior articular facet of one vertebra and the superior one of the next
Synovial
Where does the spinal cord begin
Where does it end
At the level of the foramen magnum
L1
How does the spinal cord end
What happens at S2
How do spinal nerves exit below here
It tapers time a cone shaped ending, the conus medullaris
A stalk of pia mater, the filum terminale, attaches to the end of the dural sac
From L2 to the lowest coccygeal nerve pass caudal to the conus forming the cauda equina
How do spinal nerve roots emerge(3)
Ventral motor and dorsal sensory
They form a mixed spinal nerve in the intervertebral foramen
Each nerve takes with it coverings from all 3 meningeal layers. These coverings use with the epineurium of the nerve root
How many cervical nerve roots
How many cervical vertebra
Thus: how are they organised here and in the rest of the body
8
7
C7 nerve emerges above C7 vertebra and C8 below
Below C7, all nerve roots emerge below the corresponding vertebra
Where is the spinal epidural space
What does it contain
Between the dura mater and vertebral periosteum
Loose connective tissue
Venous plexuses
Lymphatics
Where is the CSF contained
Where does it extend to in the adult
In the subarachnoid space
The lumbar cistern (S2)
Where is a lumbar puncture inserted
Why
L3/4 or L4/5 space
To avoid spinal cord which terminates at L1
How is the force from a fall directly onto shoulder transmitted through the clavicle
Though the clavicle from the acromioclavicular to the Sternoclavicular joint
How do clavicular fractures occur
DIRECT trauma to the shoulder
What disability can acromioclavicular dislocation cause
Little disability but visible swelling Over joint
What is the most commonly dislocated large joint
Which direction is most common
Glenohumeral
Anterioinferior where the head of humerus comes to lie anteriorly under coracoid process
Recurrent dislocation is common
What nerve damage can glenohumeral dislocation cause
What is the sign
Damage to axillary nerve
Paralysis of deltoid and loss of sensation in regimental badge region
What does rupture of rotator cuff lead to
Difficulty initiation abduction so patient may compensate by learning to the affected side so gravity can assist abduction before deltoid acts
What usually causes scapula fractures
What does it present as if scapulothoracic articulation is affected
High energy blunt force trauma
Posterior shoulder pain
Rotator cuff bursitis or tendinitis secondary to impingement
What can a vertical force through the spine with rotational flexion-extension movements in upright posture produce
Significant arthritic degeneration in facet joints and intervertebral discs
When is the water content of the intervertebral disc highest
Morning
What will a prolapsed L4/5 disc compress
L5 nerve root
What is spina bifida
Where is it commonest
What can happen
Incomplete fusion of posterior elements of the vertebra
In lumbar region
Meninges, spinal cord and roots may herniate through the defect posteriorly - severe neurological deficits
What separates the supraspinous and infraspinous fossae of the scapula
The spine
What are the 3 parts of the metacarpals
Base
Shaft
Head
How are metacarpal shafts joined
By transverse metacarpal ligaments and the interossei
What do the interossei muscles of the hand allow
Ad/abduction of fingers at the condyloid metacarpophalangeal joints
What kind of joints are the interphalangeal joints
Hinge
What does the radial head slide on in flexion
The capitulum of the humerus
True or false
The epicondyles are within the elbow capsule
False they are extracapsular
How is elbow stability maintained
By congruous articulation between trochlea and trochlear notch as well as the medial and lateral collateral ligaments and the anular ligament around the radial head
How does the radial nerve travel around the elbow
It perforates the lateral inter muscular septum proximal to elbow and then winds around radial neck before dividing
What kind of joint is the wrist
Synovial ellipsoid
Which carpal bones does the radius articulate with
Scaphoid and lunate
What separates the ulnar and triquetral
A fibrocartilaginous disc attached to the ulnar notch of the radius and the base of the ulnar’s styloid process
How is the wrist capsule strengthened
By medial and lateral collateral ligaments which run from the styloid processes of the radius and ulnar to the carpal bones
What characterises the skin on the palm
Flexure creases and papillary ridges
What does the palmaris brevis do
Where is it
What exception does this provide
Improves grip by stabilising skin on the ulnar side
Attached to dermis and across the base of the hypothenar eminence
Everywhere else the skin on the palm is attached to the palmar aponeurosis
What is the subcut fat of the hand divided into
Small loci by fibrous bands
Why does the pressure of gripping not impede venous return from the hand
Large subcutaneous veins drain from the palm to the dorsal Side
Describe the palmar aponeurosis
Consists of a thick, unyielding central part
Proximally receives the palmaris longus tendon and distally divides into 4 slips which are continuous with the fibrous flexor sheaths of the fingers
It is thinner over the eminences to allow greater flexibility
What supplies the thenar eminence
What about the hypothenar
Recurrent branch of Median
Ulnar
The 4 lumbricals arise from where?
Where do they insert
Tendons of flexor digitorum profundus
On the dorsal expansion
True or false
All interossei muscles are innervated by the ulnar
True
Why may a posterior elbow dislocation occur
A child falls on outstretched hands whilst ossification is still incomplete
What is a pulled elbow
Subluxation of the head of the radius out of the annular ligament
When a child’s hand is pulled by force
What is Colles’ fracture
Which age group often get it
What deformity is associated
A non articular fracture of the distal radius from a fall on the outstretched hand
Over 50s
The distal fragment is driven posteriorly and superiorly producing ‘dinner fork’ deformity
Reduction of the fracture is necessary to restore normal alignment of the radius and its articular surface
What does Bill Nighy have
How is it treated
Dupuytren’s contracture -
A contracture of the palmar fascia resulting in fixed deformities in the hand and finger joints
Surgery- removing strands of contracted fascia without damaging digital nerves
Can Tenosynovitis result in paralysis
Not nervous paralysis but trigger finger may occur when the finger remains in the flexed position
How can you get a metacarpal fracture
Direct violence
Often results in a transverse or short oblique fracture in the neck of the 5th metacarpal
This is known as the boxer’s fracture
Describe the flexion/ extension involves in the ulnar claw
Where can a compression occur to cause this
Hyper extension at the metacarpophalangeal with flexion at the proximal interphalangeal joint
In Guyon’s canal (a fibro-osseus tunnel between the pisiform and the hook of hamate)
What does Allen’s test evaluate
Collateral circulation to the hand by evaluations patency of the radial and ulnar arteries
If patients don’t have the dual blood supply to the hand what can be dangerous
Puncture or cannulation of the radial artery could lead to ischaemia in such patients
What is the primary function of the joints and muscles of a pectoral girdle and upper limb
To place the hand with precision into an almost infinite number of positions relative to the axial skeleton and to stabilise the hand/move it against resistance
When do the upper limb buds appear
Lambardes appear at the end of the fourth week
How do the bones of the upper limb develop? What is the exception?
The bones of the upper limb develop first as cartilage models which later ossify to become bone
The exception is the clavicle which develops in membrane
The bones of the upper limb Develop first as cartilage models and later ossify. What is this called?
Enchondral ossification
When does enchondral ossification begin in the upper limb
Week six
When have the digits of the hand separated
By the eighth week of development
Is the hard part of the appendicular skeleton
Only the upper and lower limbs are referred to as the appendicular skeleton
How is the upper limb connected to the axial skeleton anteriorly and posteriorly
By the pectoral girdle
anteriorly by the manubrium and not posteriorly
True or false there is a complete ring connecting the upper limb to the axial skeleton
False
What is the resting position of the shoulder
Why
Pointing forwards at about 30°
To optimise upper limb activities in front of the trunk and head
Bar one, all the joints in the upper limb are which kind of joint
What is the exception
Synovial joint
The exception is the middle radioulnar joint which is a fibrous joint formed by the radius and the ulnar with the interosseous membrane in between
Describe a synovial joint
Synovial joints have a fibrous capsule which is lined by a synovial membrane that secretes synovial fluid
How are the articulating surfaces at the end of the clavicle is atypical within the upper arm
The articular surfaces at the end of the clavicle is formed of fibrocartilage but the articular surfaces of the other joints of the upper limb are covered with hyaline cartilage
What does the combination of hyaline cartilage and synovial fluid give the joints of the upper limb
Extremely low friction and also acts as a shock absorber
Other than decreasing friction and acting as a shock absorber, what else does synovial fluid provide in joints
Nutrition for the articular surface
True or false hyaline cartilage in joints heals quickly
False
it has a poor healing ability and damage once it occurs frequently leads to progressive joint disease
What property do both hyaline cartilage and synovial fluid have
What happens if this is lost
Viscoelastic properties the optimise the function of the joints and if reduced can contribute to joint disease
What is the stability and freedom of movement of synovial joints controlled by (3)
The combination of Shape of the articular surfaces,
the capsule of the joint,
the ligaments and the muscles that cross the joints
How are the sign over your joints often described? Give examples
By the shape of the articulating surfaces
Eg
Ball and socket, saddle, hinge, plane /sliding, pivot, and condyloid
Name three movements that can occur at a synovial joint
Rolling
sliding
spinning
How are individual muscle fibres arranged
They are bundled together into fascicles which are each surrounded by perimysium
How are muscle fascicles groups together
They are bound together by a connective tissue layer called the epimysium
What do muscle spindles do
Provide sensory feedback to the central nervous system on the state of contraction of that muscle
True or false: there are sensory nerves from the joint capsules that feedback information on the position of joints
True
Which end is the origin of the muscle and which end is insertion of the muscle
The origin is at the end that moves least on contraction
How can muscles attach
Tendon
aponeurosis
fleshy
Name muscles which attach to other muscles
Lumbricals
What do parallel arrangement of muscle fibres give to the muscle
What about pennate
A greater range of movement
Pennate arrangements give increased force but at the expense of the range of movement
Which tendons can be prone to inflammation and injury
Give examples in the upper limb
Long tendons, particularly where they follow and angulated course
Long head of biceps tendon,
extensor pollicis longus
What can characteristic injury patterns be associated with
Certain arrangements of muscles and tendons for example where many muscles arise from a small area such as with “tennis elbow”
When is a muscle and agonist
When it is primarily responsible for generating a specific movement
What does it mean to say that many muscles act in synergy
Many muscles are acting on more than one joint or to produce complex movements
What are the different types of synergy
Synergists can act to reinforce the action of the prime mover or to eliminate any unwonted actions of the prime mover
What would happen if prime movers were to operate in isolation
What happens instead
The movement would be uncontrolled and ballistic
other muscles operate at the same time to control the movement of the primary
What is the 4th muscle type, Other than agonists, synergists and antagonists?
Fixator: muscles that stabilise the origin of the agonist
How many spinal nerve segments are there
31
What does each spinal nerve segment consist of
A section of the spinal-cord with a pair of spinal nerves, which are attached to the spinal-cord by a dorsal (sensory) route and a ventral (motor) root.
What forms the brachial plexus
The anterior primary rami of spinal nerves C5 – T1
The brachioplexus is solely motor fibres. True or false?
False there is a mixing of nerve fibres
What is a myotome
A group of muscles supplied by a single nerve root
Symptoms felt in the upper limb caused by compression in the cervical spine are caused by
Degenerative change
What is polyneuropathy
What can cause this
Conditions affecting many nerves
Compression or irritation of a specific peripheral nerve or by disease at the level of the neck affecting the nerve roots
When does the subclavian artery becomes the axillary artery
At the lateral border of the first rib
When does the axillary artery become the brachial artery
At the inferior border of teres major
What does the dorsal venous network of the upper limb drain into
Cephalic and basilic veins
True or false: the cephalic vein forms the axillary vein and the basilic vein joins the axillary vein
False the basilic vein forms the delivery van and cephalic vein drains into axillary vein
What are the superficial veins of the upper limb used for
Phlebotomy
Cannulation
Can the subclavian vein be used for cannulation
Yes
Lymph fluid from the upper limb drains via which nodes in the cubital fossa and then into which nodes more medially
Lymph fluid drained via the supertrochlear lymph nodes in the cubital fossa and into the axillary and infraclavicular lymph notes
Why are the axillary lymph nodes important
They can be sight of metastatic spread of disease, particularly from breast malignancy
How can you treat metastatic lymph-node’s
What can This lead to in the upper limb
Surgery or by radiotherapy
Impaired flow of lymph from upper limb leading to permanent swelling of the limb (lymphoedema)
What is a blind hand
If sensation in the area supplied by the median nerve is lost as sensation is lost in that Palmar aspect of the thumb and radio 2 1/2 digits
What are the two types of cartilagineous joint
Eg?
Primary / synchondroses - first chondrosternal joint
Secondary / symphyses- Manubriosternal joint
The pubic symphysis is which kind of joint
Secondary cartilagineous
What are the Cartesian coordinates for 6° of freedom
Objects potentially can have up to 6° of freedom – translation along any of the XYZ axes and rotation around any of these three axes
How many degrees of freedom in a ball and socket joint
Three (all rotation)
What is an ellipsoid joint
Eg
How many degrees of freedom
A condylar joint
MCP joints
2° of freedom; sometimes 3° if rotation permitted by ligaments
How many degrees of freedom in a saddle joint
2
How many degrees of freedom in a plane joint
2 (if no rotation allowed by ligaments)
How many degrees of freedom does a hinge joint have
1 (As all have collateral ligaments)
How many degrees of freedom in a swivel/pivot joint
One
How will it appear if the humeral head dislocate posteriorly in relation to the glenoid
What about anteriorly
It will appear to move laterally
Anterior dislocation shows true medial displacement
The combined joint between the radial head and proximal owner and distal humorous has how many degrees of freedom
2 (pivot joint and hinge joint)
When do the collateral joints of the Metacarpophalangeal joints become tight
Why
When the joint is flexed 90°
They are ellipsoid/condyloid joint so the collateral ligaments are attached more towards one end (ellipse) The ligaments and become tight in certain positions
Describe the axial rotation of the thumb carpometacarpal joint
What can occur
There isn’t any
Circumduction
What is another name for a triangular type muscle
Convergent
What is a fusiform muscle type
Eg
Muscles which I have fibres that run parallel to the length of the muscle and are spindle-shaped
Pronator teres
Give eg of unipennate and bipennate muscles
Unipennate: Flexor pollicis longus
Median nerve lumbricals
Bipennate: dorsal interosseus
Name four types of multi pennate configuration
Triangular / convergent
Parallel
Fusiform
Circular
What are the fixator, agonist, synergist, antagonist in a bicep curl
Fixator: deltoid
Agonist: biceps
Synergists: brachialis and brachioradialis
Antagonist: triceps
What are the agonist, synergist and fixators of the power grip
Agonist: long flexors if fingers
Synergists: Extensors of wrist to prevent wrist flexion caused by long flexors of fingers
Fixators: triceps and brachialis to stabilise elbow; pectoral girdle to stabilise shoulder
What wraps around the humeral surgical neck
Axillary nerve and vessels
