Module 06 - Upper Limb Flashcards
What is the glenohumeral joint?
It is a shoulder joint made from the large humeral head and the shallow glenoid cavity of the scapula
What is the acromioclavicular joint?
Shoulder joint made from the acromion of the scapula and the clavicle
What is the sternoclavicular joint?
Joint between the sternum and clavicle
What bones make the pectoral girdle?
Sternum, clavicle, scapula, and humerus
What are the 3 joints of the pectoral girdle?
Glenohumeral
Acromioclavicular
Sternoclavicular
What are the 4 ligaments of the pectoral girdle ?
Acromioclavicular ligament
Coracoacromial ligament
coracoclavicular ligament
glenohumeral ligaments
Location and function of the acromioclavicular ligament?
Between acromion (of scapula) and clavicle Reinforces the acromiclavicular joint and supports the superior surface of the shoulder
Location and function of the coracoacromial ligament?
Connects the acromion and coracoid process (both on scapula)
Forms a vault that prevents the displacement of the humeral head superiorly
Location and function of the coracoclavicular ligament?
Connects the coracoid process (scapula) and the clavicle
Main Stabilizer of the acromioclavicular joint, because it anchors the clavicle to the coracoid process of the scapula
Location and function of the glenohumeral ligaments?
Connects the humerus to the scapula
Stabilizes the glenohumeral joint, especially during the adduction of the arm
largest ligaments in the pectoral girdle + cannot be seen from a superior view
What type of joint is the glenohumeral joint?
Ball and socket joint
What provides the glenohumeral joint with extensive mobility? (2)
Poor fit of the articular surfaces
Loose fibrous capsules
What is the glenoid labrum + function?
Rim of fibrocartilage that deepens the glenoid cavity
Improves stability of the glenohumeral joint
What are the 4 muscles that make up the rotator cuff?
supraspinatus
infraspinatus
teres minor
subscrapularis
What is the function of the rotator cuff
stabilizes the shoulder joints, also called “dynamic ligaments”
What structure is also referred to dynamic ligaments?
rotator cuff
What muscle, that is not part of the rotator cuff, helps stabilize the joint?
the biceps brachii
Its long head attaches the to superior glenoid tubercle of the scapula
What are bursae?
fluid-filled (synovial fluid) sacs lined by synovial membranes that provide cushioning between bones, tendons, and muscles, and prevents friction between them
What is the function of the subacrominal bursa?
Protects supraspinatus muscle by:
Separating the surface of the supraspinatus tendon from the acromion, the coracoid, and the coraco-acromial ligrament superiorly
What is the function of the subdeltoid bursa?
Protects supraspinatus muscle by:
Separating the deep surface of the deltoid muscles from the shoulder joint
What is shoulder bursitis?
Inflammation and thickening of the bursae due to an increased amount of friction
Results from repetitive motion (ex: baseball pitcher)
Symptoms:
-excessive swelling in the region of the shoulder
- warmth at the site of inflammation
- pain with movement/pressure at the shoulder
What are scapulohumeral muscles?
Connect the humerus to the scapula and functions to stabilize the glenohumeral joint
What are the 2 scapulohumeral muscles? (in this class)
teres major
supraspinatus
Origin, insertion and action of teres major?
origin:
inferior part of the lateral border of the scapula
insertion:
medial lip of the intertubercular sulcus on the humerus
action:
extension and medial rotation of the humerus
Origin, insertion and action of supraspinatus?
Origin: Superior part of the scapula Insertion: Tubercle of the humerus Action: Initiates abduction of the humerus
Describe the location of each rotator cuff muscle in relation to each other and the neighbouring bony structures
Supraspinatus
originate in the supraspinous fossa of the scapula, superior to the scapular spine
Infraspinatus
originates in the infraspinous fossa of the scapula, inferior to the scapula spine and superior to the teres minor
Subscapularis
originates in the subscapular fossa and is anterior to the other 3 rotator cuff muscles. It is inferior to the coracoid process
Teres minor
inferior most of the rotator cuff and posteriot to subscapularis
What is a supraspinatus tear and include causes and symptoms
Rupture of the tendon near the site of insertion - fairly common due to this tendon being easily pinched or torn between greater tubercle of humerus and acromion of scapula Causes: History of trauma, increased age, typically occur when lifting something heavy or lifting something heavy too quickly Symptoms - audible pop at time of injury - rapid onset of shoulder pain - swelling at shoulder -reduced range of motion
What are the 3 muscles of the anterior compartment of the arm?
Biceps brachii
Brachialis
coracobrachialis
What is the function of the biceps brachii?
flexion of the forearm at the elbow
supination of the forearm
What is the function of the brachialis?
flexion of the forearm at the elbow
What is the function of the coracobrachialis?
flexes the arm at the glenohumeral joint
What is the muscle of the posterior compartment of the arm
Triceps brachii
Describe the anatomy of the triceps brachii
3 heads:
- A long head from the infraglenoid tubercle of scapula
- Lateral and medial heads from the posterio surface of the humerus
All 3 heads insert at a common tendon, the triceps tendong, at the olecranon of the ulna
What is the function of the triceps brachii
extension of the elbow
What is triceps tendonitis?
Overuse injury resulting in inflammation and thickening of the triceps tendon at its insertion on the olecranon process
What is the cubital fossa?
Triangular depression located on the anterior surface of the elbow joint (creux du coude)
Contains important neurovascular structures
analogous to the popliteal fossa
What are the structures that make the borders of the cubital fossa?
Lateral: brachioradialis
Medial: Pronator teres
Superior: imaginary line between the humeral epicondyles
What are the 3 main structures that pass through the cubital fossa?
- tendon of the biceps brachii
- brachial artery (which split into the ulnar and radial artery)
- median nerve
What causes the “Popeye deformity”?
Distal biceps tendon rupture
What are the 3 joints of the elbow?
humeroradial joint
humeroulnar joint
superior (proximal) radioulnar joint
What is the humeroradial joint?
joint between the capitulum of the humerus and concave head of the radisu
What is the humeroulnar joint?
Joint between the trochlea of the humerus and trochlear notch of the ulna
What is the superior (proximal) radioulnar joint?
Synovial joint between the head of the radiaus and the radial notch of the ulna.
What is a lateral epicondylitis?
AKA tennis elbow, common overuse injury of the elbow region related to the extensor muscles of the forearm.
Tiny tears from overuse may occur at the tendinous origin
Most common tendon: extensor carpi radialis brevis
What are the 2 joints of the forearm?
Proximal radioulnar joint
Distal radioulnar joint
What are the 2 ligaments of the forearm?
annular ligament
interosseous membrane
describe the anatomy and function of the annular ligament
Encircles the of the radius
Holds the radius against the radial notch of the ulna
What is the interosseous membrane and what is its function?
Fibrous joint that spans the space between the ulna and radius
Divides the forearm into anterior and posterior compartments
What is the distal radioulnar joint?
formed between the head of the ulna and the ulnar notch of the radius
What is a radial head subluxation?
Aka nursemaid’s elbow, or pulled elbow.
Partial dislocation of the radioulnar joint
typically seen in young children
What are the muscles in the anterior compartment of the forearm?
Pronator teres Flexor digitorum superficialis Flexor digitorum profundus Flexor pollicis longus Pronator quadratus
What is the most superficial muscle of the anterior compartment of the forearm?
Pronator teres
What is the intermediate muscle of the anterior compartment of the forearm?
Flexor digitorum superficialis
What are the 3 deep muscles of the anterior compartment of the forearm?
- Flexor digitorum profundus
- Flexor pollicis longus
- Pronator quadratus
What is pronator teres syndrome?
Repetitive pronation of the forearm (ex: using a screwdriver) may cause pronator teres hypertrophy, which can entrap the median nerve
- pain in anterior forearm. along the path of the median nerve
- significant weakness when flexing the wrist due to impaired moto innervation
- numbness and tingling of the skin on the hand and first 4 digits
What is the muscle of the posterior compartment of the forearm (superficial layer only for this class)
Extensor digitorum
extends digits and wrists
What are the 8 bones of the wrist and how are they arranged?
Lateral to medial** Proximal row: scaphoid, lunate, triquetrum, pisiform Distal row: trapezium, trapezoid, capitate, hamate
mnemonic proximal: lateral to medial distal: medial to lateral In a clockwise manner So Long To Pinky, Here Comes The Thumb
What are the 3 joints of the wrist?
Intercarpal joints
Midcarpal joints
Radiocarpal (wrist) joints
Describe the intercarpal joints
Synovial plane joints between the carpal bones
Capable of slight gliding movements
Describe the midcarpal joints
Continuous space between the proximal and distal rows of carpal bones
Capable of slight gliding movements
Describe the radiocarpal (wrist) joint
Biaxial, synovial, ellipsoidal (condyloid) joint formed between the distal end of the radius and the proximal row of carpal bones, except pisiform
It functions in extension, flexion, abduction, adduction and circumduction
What is the carpal tunnel?
Concavity formed by the anterior surface of the carpal bones (posterior border) and the flexor retinaculum (anterior border)
What structures pass through the carpal tunnel?
Median Nerve
9 flexor tendons (4 flexor digitorum superficialis, 4 flexor digitorum profundus, and flexor pollicis longus) from the forearm to the hand
What is the extensor retinaculum?
Broad ligamentous sheet located at the dorsal aspect of the wrist
Holds the tendons in place
What are the hypothenar muscles of the hand?
Located on the medial anterior aspect of the hand
Responsible for the movement of the 5th digit
What are the thenar muscles of the hand?
Located on the lateral anterior aspect of the hand (chubby base of the thumb)
Responsible for the movements of the thumb
What are the 2 types of interosseous muscles of the hand?
Dorsal interossei
Palmar interossei
What is the function of dorsal interossei muscles?
Finger abduction
What is the function of palmar interossei muscles?
Finger adduction
What is the flexor retinaculum?
Broad ligamentous sheet located on the anterior aspect of the wrist, forms the anterior border of the carpal tunnel
Describe the superficial palmar arch
Ulnar artery passes superficial to the flexor retinaculum, entering the palm to form the superficial palmar arch - completed by the radial artery
Arch is located superficial to the long flexor tendons of the hand
What is the function of the superficial palmar arch?
4 branches supply the medial three and a half fingers (vascular)
Describe the deep palmar arch
Radial artery curves dorsally to enter the deep part of the palm as the deep palmar arch which is completed by the deep branch of the ulnar artery
What is the function of the deep palmar arch
Vascular supply of the thumb and lateral aspect of the index
What are the 3 nerves that innervate the hand?
Ulnar nerve
Radial nerve
median nerve
What does the ulnar nerve innervate?
Cutaneous branches supply the medial third of both the palm and dorsum of the hand + palmar and dorsal surfaces of both the little finger and medial half of the ring finger
What does the median nerve innervate in the hand?
Cutaneous innervation to the skin of the lateral 2 thirds of the palm, palmar surfaces of the lateral 3 &1/2 digits, and the dorsum of the distal halves of the same digits
What does the radial nerve innervate?
Superficial brand passes from anterolateral aspect of forearm to dorsum of the hand - giving cutaneous branches tot he lateral 2/3 of the dorsal surface of the hand and to the dorsal surface of the lateral 3&1/2 digits over the proximal phalanges
What is hypothenar hammer syndrome?
Trauma to the palmar portion of the ulnar artery may occur with repetitive movements or physical trauma to the hypothenar region (like hammering)
Compresses the ulnar artery
Ischemia, discolouration, paresthesia, and temperature sensitivity of the digits 2-5
