Upper limb anatomy Flashcards
(73 cards)
1
Q
If a patient has a problem in a limb, such as pain, limited movement of weakness, what could it be a problem with in terms of:
- bone
- muscles and tendons
- joints
- neurological
A
Bone- Fractures, dislocation, infections
Muscles and tendons- muscle disease, muscle weakness, muscle ischemia
Joints - degeneration or inflammation of the articular cartilage, excess fluid in the joint (causing pain and stiffness), infection, debris in the joint
Neurological- in relation to pathology of the brain, spinal cord, peripheral nerves, neuromuscular junction
2
Q
Which part of the upper limb is the pectoral girdle?
A
- The clavicle, scapula and muscles attach to these bones
3
Q
Which part of the upper limb is considered the arm? What is the bone of the arm called?
A
The region between the shoulder and elbow joints.
The bone of the arm is called the humerus
(contains anterior and posterior muscle compartments)
4
Q
Which part of the upper limb is considered the forearm? what are the bones of the forearm called?
A
The region between the elbow and wrist joints.
The bones of the forearm are the radius and ulna.
(contains anterior and posterior muscle compartments)
5
Q
Which part of the upper limb is considered the hand? What are the 2 surfaces of the hand?
A
- The area distal to the wrist
- The palm and the dorsum
(it contains many small muscles)
6
Q
What is the glenohumeral joint of the upper limb? What type of joint is it? What does it articulate? is it mobile?
A
- The shoulder join. It is a ball and socket joint formed by the articulation between the scapula and proximal humerus.
- It is highly mobile
7
Q
What type of joint is the elbow joint? What does it articulate?
A
- It is a synovial hinge joint formed by the articulation of the distal humerus with the ulna and radius
8
Q
What type of joints are the proximal and distal radioulnar joints? What actions do they allow?
A
- They are pivot joints
- They allow supination and pronation of the forearm and hand
9
Q
What is the radiocarpal joint? What type of joint is it? What does it articulate with?
A
- It is the wrist joint
- It is a condylar joint
- It articulates with the distal radius and 2 carpal bones
- It allows for flexion, extension, abduction and adduction
10
Q
What does the clavicle articulate with and what are the joints called?
A
- It articulates with the sternum medially (sternoclavicular joint) and it articulates with the acromion of the scapula laterally (acromioclavicular joint)
11
Q
What is the glenoid fossa? Is it a good or poor fit?
A
It is located at the lateral aspect of the scapula
It articulates with the proximal humerus to form the glenohumeral joint.
It is actually a poor fit for the humerus but stability is compromised in return for an increased range of motion
12
Q
What is located superior and inferior to the glenoid fossa?
A
The supraglenoid tubercle and infraglenoid tubercle
13
Q
What is the anatomical neck of the humerus?
A
- A groove in the head of the humerus
14
Q
State 2 ways in which the axillary nerve may be injured
A
- Dislocation of the humeral head
- Fracture of the surgical neck
15
Q
What is the part of the humerus just distal to the lesser tubercle of the humerus? What is its significance? What could result from a fracture of it or dislocation of the humerus?
A
Just distal to the tubercles, the bone of the humerus narrows and becomes continuous with the shaft- this is called the surgical neck of the humerus
This is clinically important because it is commonly fractured (especially in the elderly as the result of a fall)
Should the surgical neck be fractured or the humeral head be dislocated, the axillary nerve running close to this region can be injured. Axillary nerve innervates the deltoid muscle and teres minor.
16
Q
What is the protuberance in the upper lateral aspect of the humeral shaft called? What is its function?
A
- The deltoid tuberosity
- The site of attachment for the deltoid muscle
17
Q
Where is the radial groove located and what does it mark the path of?
A
- Located on the posterior humerus, inferior to the deltoid tuberosity
- It marks the path of the radial nerve. As the radial nerve runs very close to the humeral here, it can be injured if there are midshaft humeral fractures.
18
Q
What is the coracoid process?
A
- A hook like structure on the lateral edge of the superior portion of the scapula. It works with the acromion to stabilise the shoulder joint.
19
Q
What are the movements of the scapula?
A
Protraction- pushing a door
Retraction- squaring your shoulders
Elevation- Shrugging
Depression- lowering your shoulders
Rotation- The glenoid fossa tilts cranially to aid in the elevation of the upper limb. When raising your arm above your head, for every 2 degrees of abduction of your shoulder, the scapula rotates 1 degree.
20
Q
What are the 5 muscles of the pectoral girdle? Which are anterior/posterior?
A
- The pectoralis major, minor and serratus anterior (anterior)
- The trapezius and latissimus dorsi are posterior
21
Q
What do the posterior muscles of the pectoral girdle connect to?
A
- They connect extensively to the vertebral column (trapezius connects to the skull)
- Latissimus dorsi attaches to the anterior aspect of the proximal humerus.
22
Q
What muscles attach the medial border of the scapula to the vertebral column?
A
- Levator scapulae
- Rhomboid minor
- Rhomboid major
23
Q
Which muscles move the scapular, and specifically which actions do these muscles help with?
A
Trapezius; upper part- elevation, lower part, depresses. middle part, retracts. also rotates the scapula
Levator scapulae- elevates
Rhomboid major- retracts
Rhomboid minor- retracts
24
Q
Which muscles move the scapular, and specifically which actions do these muscles help with?
A
Trapezius; upper part- elevation, lower part, depresses. middle part, retracts. also rotates the scapula
Levator scapulae- elevates
Rhomboid major- retracts
Rhomboid minor- retracts
25
What does the latissimus dorsi attach to and what action does it create?
- It is attached to the anterior proximal humerus. It extends, adducts and medially rotates the humerus
26
What are the origins and insertions of the
Trapezius
Latissimus dorsi
Levator scapulae
Rhomboid minor
Rhomboid major?
Trapezius---- skull, cervical and thoracic vertebrae ---- clavicle and scapula
Latissimus dorsi---- lower thoracic vertebrae ---- humerus upper anterior
Levator scapulae-- upper cervical vertebrae --- scapula medial border
Romboid minor--- C7 and T1 -- Scapula medial border
Rhomboid major- Thoracic vertebrae ---scapula medial border
27
Most of the muscles of the posterior pectoral region are innervated by the brachial plexus. What is the trapezius and latissimus dorsi innervated by?
- The trapezius is innervated by the spinal root of CN XI (accessory nerve)
- The latissimus dosi is innervated by the thoracodorsal nerve
28
What are the 6 muscles that attach the scapula to the humerus? Where are they found?
deltoid
supraspinatus
infraspinatus
subscapularis
teres minor
teres major
Apart from the deltoid, they are all found deep to the posterior scapula muscles.
29
What muscles make up the rotator cuff and what is the purpose of the rotator cuff?
supraspinatus
infraspinatus
subscapularis
teres minor
The rotator cuff provides stability to the shoulder joint.
30
What does the deltoid attach? Where does it insert on the humerus? Can the deltoid initiate abduction of the shoulder joint?
It attaches the humerus to the lateral part of the clavicle and to the spine of the scapula.
It inserts to the deltoid tuberosity on the humerus
The deltoid cannot initiate abduction of the shoulder joint, another muscle abducts the first 20 degrees before the deltoid muscle takes over
31
What is the deltoid innervated by?
What happens if the axillary nerve is injured?
- The axillary nerve
- It can lead to atrophy and weakness of the deltoid
32
What is the action of the deltoid at the shoulder joint? What is its origin? What is its insertion point?
- It abducts the shoulder beyond 20 degrees
- Its origin is the spine and acromion
- its insertion point is the deltoid tuberosity
33
What is the action of the teres major at the shoulder joint? What is its origin? What is its insertion point?
- Medial rotation and adduction of the shoulders
- Origin is posterior surface of the scapula, on the inferior part of the lateral border
- Its insertion point is the anterior aspect of the humerus
34
What is the action of the supraspinatus at the shoulder joint? What is its origin? What is its insertion point?
- Abducts the shoulder for the first 20 degrees
- originates in the supraspinous fossa on the posterior border of the scapula
- its insertion point is the greater tubercle of the humerus (superior facet)
35
What is the action of the infraspinatus at the shoulder joint? What is its origin? What is its insertion point?
- It laterally rotates the shoulders
- It originates from the infraspinous fossa on the posterior border of the scapula
- Its insertion point is the greater tubercle of the humerus (middle facet)
36
What is the action of the teres minor at the shoulder joint? What is its origin? What is its insertion point?
- It laterally rotates the shoulders
- It originates from the posterior surface and lateral border of the scapula
- Its insertion point is the greater tubercle of the humerus (inferior facet)
37
What is the action of the subscapularis at the shoulder joint? What is its origin? What is its insertion point?
- It medially rotates the shoulders
- It originates from the subscapular fossa on the anterior surface of the scapula
- Its insertion point is the lesser tubercle of the scapula
38
What is the quadrilateral space bordered by? What is the significance of this?
- superiorly - teres major
- Inferiorly - teres minor
- Laterally- surgical neck of the humerus
- Medially- long head of the tricpes
- The axillary nerve passes through this to enter the posterior scapula region to innervate the deltoid and teres minor.
39
What is impingement?
As the supraspinatus travels from the supraspinous fossa to the greater tubercle, it travels under the acromion.
The tendon can become inflamed and pinched between the acromion and humerus during movements of the shoulder.
40
What are 2 other things that contribute to shoulder joint stability?
- Glenoid labrum- rim of fibrocartilage around the margin of glenoid fossa that deepens the shallow fossa to aid stability
- The capsule of the shoulder joint is reinforced with ligaments
41
What separates the anterior and posterior compartments of the arm?
- Intermuscular septa
42
Where does the triceps brachii originate from and where does it attach to? What happens when it contracts?
- It is found in the posterior compartment of the arm
- It has 3 muscle heads which converge via a common tendon on the olecranon of the ulna
- The muscle crosses the posterior aspect of the elbow joint, therefore when it contracts, the elbow extends.
43
Where does the triceps brachii originate from and where does it attach to? What happens when it contracts?
- It is found in the posterior compartment of the arm
- It has 3 muscle heads which converge via a common tendon on the olecranon of the ulna
- The muscle crosses the posterior aspect of the elbow joint, therefore when it contracts, the elbow extends.
44
What are the 3 heads of the triceps and where do they originate? What nerve are they innervated by?
Long head: infraglenoid tubercle of the scapula (most medial part of triceps)
Lateral head: posterior humerus, proximal to the radial groove
Medial head: posterior humerus, distal to the radial groove
They are all innervated by the radial nerve.
45
Where does the long thoracic nerve originate and what does it supply?
How can it be damaged?
- It arises directly from the roots of the brachial plexus (C5, C6, C7)
- It supplies the serratus anterior
- it can be damaged via surgery, radiotherapy or disease of the axilla
46
What are the 6 boundaries of the axilla?
Anterior wall - Pectoralis major and pectoralis minor
Posterior wall - Subscapularis, teres major and latissimus dorsi
Lateral wall - upper humerus
Medial wall - serratus anterior and chest wall
Apex- first rib, clavicle and scapula (passage between the neck and the axilla)
Base - skin and fascia between the chest wall and arm
47
Tell me about the axillary artery (what is it a branch of, how many branches does it branch into, what does it continue to become?)
It is a branch of the subclavian artery
The axillary artery gives rise to several branches. 1 above pectoralis minor, 2 behind it and 3 below it.
The axillary artery continues into the arm as the brachial artery
48
Tell me about the axillary vein (what does it drain, where does it drain into, what is the union that forms it)
It is a large vein which drains the upper limb and is continuous with the subclavian vein
It travels alongside the axillary artery
It is formed by the union of the deep veins of the arm and the basilic vein.
If either the axillary artery or vein is punctured or injured, it can cause life threatening bleeding.
49
What is the brachial plexus?
It is the network of nerves that provide motor and sensory innervation to the upper limb
50
Where do the spinal nerves of the brachial plexus arise? And what are the 5 segments of the brachial plexus?
The spinal nerves arise from the lower cervical and upper thoracic vertebrae C5-8 and T1.
The 5 segments are: roots, trunks, divisions, cords and branches
51
What are the roots of the brachial plexus?
The 5 spinal nerves exiting the spinal cord and collectively giving rise to the brachial plexus
52
What are the trunks of the brachial plexus?
C5 and C6 combine to form the superior trunk
C7 continues as the middle trunk
C8 and T1 combine to form the inferior trunk
53
What are the divisions of the brachial plexus?
Each trunk divides into an anterior and posterior division under the clavicle
54
What are the cords of the brachial plexus?
Anterior divisions of the superior and middle trunk combine to form the lateral cord
Posterior divisions of all trunks combine to form the posterior cord
Anterior divisions of the inferior trunk continues as the medial cord
55
Draw the brachial plexus
see diagram
56
What are the branches of the brachial plexus?
Musculocutaneous - branch from the lateral cord
Axillary - branch from the posterior cord
Median - formed by branches of the lateral and medial cords
Radial - branch of the posterior cord
Ulna - branch from the medial cord
57
Tell me about the axillary nerve in relation to motor and sensory innervation and position in the brachial plexus (which cord and spinal fibres). How is it vulnerable to injury? How would you test for injuries with the axillary nerve? (motor and sensory)
Teres minor and deltoid
Skin over the upper lateral arm (inferior portion of deltoid- sergeant badge area）
Posterior cord
C5 and C6
Fracture of the surgical neck or a dislocation of the humeral head
Abduction of shoulders (raising them up)
No sensation in the skin over the upper lateral arm (above the deltoid)
58
Tell me about the radial nerve in relation to motor and sensory innervation and position in the brachial plexus (which cord and spinal fibres). How is it vulnerable to injury? How would you test for injuries with the radial nerve? (motor and sensory)
Triceps brachii and all muscles in the posterior compartment of the forearm (extensors of wrist and digits)
Skin on the medial part of the dorsum of the hand. Skin over posterior arm and forearm
Posterior cord
C5 - T1
Fracture of the midshaft of the humerus.
Extension of elbows. Movement and sensation of wrist may also be impaired
No sensation in the skin on the dorsum of the thumb.
59
Tell me about the musculocutaneous nerve in relation to motor and sensory innervation and position in the brachial plexus (which cord and spinal fibres). How is it vulnerable to injury? How would you test for injuries with the musculocutaneous nerve? (motor and sensory)
Three anterior muscles of the arm: Biceps brachii, brachialis, coracobrachialis
Region of skin over the lateral half of anterior forearm
Lateral cord
C5 - C7
Not in a place that is frequently injured
60
Tell me about the median nerve in relation to motor and sensory innervation and position in the brachial plexus (which cord and spinal fibres). How is it vulnerable to injury? How would you test for injuries with the median nerve? (motor and sensory)
Muscles in the anterior forearm (flexors of wrist and digits), innervates small muscles of the thumb
Skin over the lateral aspect of the palm of the hand and palmar surface of lateral digits
Lateral and medial cord
C6 - T1
Crosses anterior aspect of elbow in the cubital fossa - so fracture of the humerus or damage at the wrist due to carpal tunnel syndrome
Weakness or paralysis of thumb
No sensation in the skin of the lateral aspect of palm or lateral digits
61
Tell me about the ulnar nerve in relation to motor and sensory innervation and position in the brachial plexus (which cord and spinal fibres). How is it vulnerable to injury? How would you test for injuries with the ulnar nerve? (motor and sensory)
Most of the small muscles in the hand (vital for fine movements of digits)
Skin over the medial aspect of the hand and palmar surface of medial digits
Medial cord
C8 - T1
Most injuries occur behind the medial epicondyle (being superficial in that region)
Loss of coordination of fingers
No sensation in the medial aspect of the palm of the hand or the medial digits
62
What is the most catastrophic type of brachial injury?
When the 5 roots of the brachial plexus are injured as it effectively denervates the whole upper limb.
63
Where does the biceps brachii lie? Where do its heads attach? Where do the heads converge?
It lies most superficially in the anterior arm.
It has 2 heads. The long head attaches to the supraglenoid tubercle and the short head to the coracoid process.
The two heads converge via a single tendon onto the radial tuberosity of the radius. The tendon of the long head pierces the capsule of the shoulder joint and helps to stabilise the shoulder joint.
64
Is the biceps a flexor or extensor? What of. Does it help with supination or pronation of the arm when the elbow is flexed?
It is a flexor of the elbow (also contributes to flexion of the shoulder)
It aids with supination of the arm when the elbow is flexed (turning screwdriver)
65
Where does the brachealis lie? What is it attached to? Is the brachealis a flexor or extensor? What of
It lies deep to the biceps brachii.
Proximally, it is attached to the anterior aspect of the lower half of the shaft of the humerus. Distally, it crosses the elbow joint to insert on the ulna tuberosity.
It is a flexor of the elbow joint. (means it crosses the elbow joint)
66
Where is the coracobrachialis found? What is it attached to? Is it a flexor or extensor? What of.
In between the brachialis and the medial head of the triceps.
It attaches proximally to the coracoid process of the scapula and distally to the medial aspect of the middle part of the humerus.
It is a weak flexor of the shoulder joint
67
What is the cubital fossa and what are the 3 borders?
It is the region anterior to the elbow joint.
It is triangular shaped with 3 borders
Lateral border: Brachioradialis (posterior forearm muscle)
Medial border: pronator teres (anterior forearm muscle)
Superior border: (imaginary line) drawn between the medial and lateral epicondyles.
Apex is just the most distal.
68
What can be found in the cubital fossa?
The tendon of the biceps brachii
Bicipital aponeurosis
Brachial artery
Median and radial nerve
Superficial veins
69
What is the bicep tendon?
It is the tendon that is palpable in the cubital fossa
A bicep hammer can be used to examine bicep reflex
70
What is a bicipital aponeurosis? What is its function?
A fascial extension of the biceps tendon. It functions to separate the superficial veins from the brachial artery and the median nerve.
71
Where does the brachial artery lie in regards to the bicep tendon? How does the brachial artery flow e.g. what is the path of it since subclavian artery becomes axillary artery which becomes brachial artery.
The brachial artery lies medial to the bicep tendon in the cubital fossa
It is easily palpable and it bifurcates to form the radial and ulnar arteries
It is possible for the brachial artery to be punctured during cannulation and venepuncture (so extra care must be taken)
72
Where does the median nerve lie, what is it medial to? Does it innervate the muscles of the arm, forearm or hand?
It lies medial to the brachial artery
It does not innervate muscles of the arm but travels through the anterior compartment of the arm and the cubital fossa to get to the anterior forearm and hand.
73
Where does the radial nerve pass?
It passes through the lateral aspect of the cubital fossa and lies deep to brachioradialis.
