Shoulder and Deltoid Pg 60-71 Flashcards
What is the shoulder?
articulation of the head of humerus and the glenoid cavity of scapula
What is the main function of the shoulder?
To place the hand in a position to grasp efficiently
Where does the clavicle attach?
attaches to the sternum medially and the acromion process of the scapula laterally
The clavicle is located above and anterior to which rib ?
first rib
What are two functions of the clavicle?
acts as a strut to hold the scapula and shoulder in place laterally
protects the subclavian vessels and the brachial plexus and azxillary vessels as they enter arm
Where is the most frequent break in the clavicle located and what does this look like?
Between the middle and lateral third of the clavicle
Shoulder droops
Why does the shoulder droop when the clavicle breaks between the middle and lateral third of the clavicle?
Sternocleidomastoid muscle pulls the medial fragment upwards
Trapezius cannot hold up the lateral fragment due to the weight of the upper limb
Deltoid muscle and gravity pulls lateral fragment down and medially
What can happen if the broken pieces of the clavicle have jagged edges?
The jagged edges of the clavicle can damage the subclavian artery and the brachial plexus running deep to it
WHAT IS IMPORTANT TO KNOW ABOUT THE SUPRASCAPULAR NOTCH?
the suprascapular notch is enclosed by the superior transverse ligament (aka suprascapular ligmant)
THE SUPRASCAPULAR ARTERY RUNS OVER THE SUPERIOR TRANSVERSE LIGAMENT
THE SUPRASCAPULAR NERVE RUNS UNDER THE SUPERIOR TRANSVERSE LIGAMENT
*The army goes over the bridge. The navy goes under the bridge
What is the function of the glenoid labrum?
fibrocartilaginous ring that deepens the shoulder socket to provide more stability
Which part of the humerus is most likely to fracture or thin?
Surgical neck (because it is the narrowest part of the humerus)
WHAT STRUCTURES CAN GET DAMAGED IF THE SURGICAL NECK OF THE HUMERUS IS FRACTURED?
AXILLARY NERVE AND THE POSTERIOR HUMERAL CIRCUMFLEX ARTERY
WHAT SYMPTOMS WILL THE PATIENT EXHIBIT IF THE AXILLARY NERVE IS DAMAGED?
WEAKNESS/LOSS OF ABDUCTION OF ARM AND SENSORY LOSS OVER LATERAL SHOULDER (NUMBNESS)
What does the axillary nerve innervate?
Supplies sensory innervation to the skin of the lateral arm
Supplies motor innervation to the deltoid and teres minor muscles
WHAT NERVE MAY GET DAMAGED WITH A FRACTURE OF THE HUMERAL SHAFT?
RADIAL NERVE
WHAT HAPPENS IF YOU DAMAGE THE DEEP BRANCH OF THE RADIAL NERVE?
CANNOT EXTEND WRIST (WRIST DROP), THUMB, AND METAPHALANGEAL JOINT
WHAT HAPPENS IF YOU DAMAGE THE SUPERFICIAL BRANCH OF THE RADIAL NERVE?
LOSS OF SENSATION OVER RADIAL DISTRIBUTION OF THE HAND
WHAT HAPPENS IF YOU DAMAGE THE ORIGIN OF THE RADIAL NERVE?
GET BOTH DEEP AND SUPERFICIAL DAMAGE IN ADDITION TO LOSS OF ARM EXTENSION AND LOSS OF SENSATION OVER POSTERIOR ARM AND FOREARM
The greater tubercle of the humerus is the site of insertion for which muscles?
Supraspinatous, Infraspinatous, and Teres minor
Lesser tubercle of the humerus is the site of insertion for which muscle?
subscapularis
What two structures run along the spiral (radial) groove which is found on the posterior shaft of the humerus?
Radial nerve
Profunda brachii artery
Function of sternoclavicular joint
allows for elevation, depression, protraction, retraction, and circumduction of shoulder
What is the function of the acromioclavicular joint?
resists the upward motion of the head of humerus
What happens if the acromioclavicular ligament is ruptured?
Separation of shoulder
List the four ligaments found in the glenohumeral joint
Coracohumeral
Glenohumeral
Transverse humeral
Coracoacromial
List the muscles that make up the rotator cuff?
Supraspinatous, Infraspinatous, Teres minor, and Subscapularis
The glenohumeral joint is innervated by what nerves?
Axillary nerve
Suprascapular nerve
Lateral Pectoral nerve
What arteries supply the glenohumeral joint?
Suprascapular artery
Anterior humeral circumflex artery
Posterior humeral circumflex artery
What are the 3 joints of the shoulder?
Sternoclavicular joint
Acromioclavicular joint
Glenohumeral joint
What two veins merge to form the axillary vein?
Brachial vein and superficial basilic vein
Where are superficial veins in the upper extremity found and where do they drain?
They are found in the subcutaneous tissues and drain into the deep veins
Which veins are used for drawing blood, parenteral injections and starting IVs?
Superficial veins are the primary veins used and most commonly the:
Basilic vein
Cephalic vein
Median cubital vein
What is the course of the basilic vein?
The basilic vein runs medially and eventully joins the brachial vein to form axillary vein
What is the course of the cephalic vein?
The cephalic vein runs laterally and enters the clavipectoral triangle to join the axillary vein
What vein is found in the cubital fossa and connects the cephalic and basilic vein?
Median cubital vein
What structures run under the median cubital vein?
biceps tendon
brachial artery
median nerve
Why are superficial veins important during exercise?
Physical activity cause increase in arterial blood pressure which increases pressure within the muscle fascia leading to improper function of deep veins. The body compensates by utilizing superficial veins to carry blood back to the heart upon muscle exertion since the superficial veins are not next to arterial vessels or in fascial sheaths
Peripheral cutaneous nerves that branch off of axillary nerve innervate ?
skin over the deltoid
Peripheral cutaneous nerves supply what?
They provide sensory information to specific areas of skin
Palmar cutaneous branches of the radial nerve innervate?
thumb
Palmar cutaneous branches of the median nerve innervate?
skin over middle fingers
Palmar cutaneous branches of the ulnar nerve innervate?
innervates skin over the little finger
What branches from the musculocutaneous nerve after the musculocutaneous nerve has innervated the biceps brachii, brachialis, and coracobrachialis muscles?
Lateral cutaneous nerve
What does the lateral cutaneous nerve (that branches from the musculocutaneous nerve) innervate?
lateral aspect of the forearm
What is the course of the radial nerve?
The radial nerve runs along radial groove (aka spiral groove) of humerus and past the triangular interval
What does the radial nerve innervate?
triceps brachii, extensors in forearm, and skin on posterior aspect of arm and forearm
What artery runs alongside radial nerve?
profunda brachii artery
A fracture that involves the shaft of the humerus often damages what nerve?
Radial nerve
What nerve runs along the surgical neck of humerus?
Axillary nerve
A fractured surgical neck of the humerus may lead to what type of nerve damage?
Axillary nerve damage
The axillary nerve passes through what space?
quadrangular space
The axillary nerve innervates ?
teres minor, deltoid, and the skin over the deltoid (lateral shoulder)
Which artery runs alongside axillary nerve?
Posterior humeral circumflex artery
What two structures are associated with the suprascapular notch?
Suprascapular ligament runs along top of the suprascapular notch to create the suprascapular foramen
Suprascapular nerve runs under the suprascapular ligament
Suprascapular artery runs above the suprascapular ligament
Suprascapular nerve innervates?
Supraspinatous and Infraspinatous
What artery supplies supraspinatous?
Suprascapular artery
What artery supplies infraspinatous?
Suprascapular artery
Circumflex scapular artery
What artery supplies teres minor?
Suprascapular artery
Dorsal scapular artery
What artery supplies teres major?
Posterior circumflex humeral artery
Thoracodorsal branch of subscapular
What artery supplies deltoid?
Thoracoacromial artery
Subscapular artery
Circumflex humeral artery
Deep brachial artery
What artery supplies subscapularis?
Suprascapular artery
Axillary artery
Subscapular artery
What muscles make up rotator cuff?
Supraspinatous
Infraspinatous
Teres minor
Subscapularis
What is function of rotator cuff?
Move humerus
Hold head of humerus in glenoid fossa
Prevent shoulder subluxation with movement
MAINTAINS THE STABILITY OF SHOULDER
If any muscle of the rotator cuff is damaged or paralyzed, what results?
Sublaxation of head humerus from glenoid cavity
What two structures run along spiral groove of posterior side of humerus and are thus in jeopardy with fracture of humeral shaft?
Radial nerve
Profunda brachii artery
WHAT STRUCTURES RUN OUT OF THE QUADRANGULAR SPACE (UPPER EXTREMITY)?
AXILLARY NERVE
POSTERIOR CIRCUMFLEX HUMERAL ARTERY
WHAT ARE BOUNDARIES OF QUADRANGULAR SPACE?
TERES MINOR
TERES MAJOR
LONG HEAD OF TRICEPS (MEDIALLY)
SURGICAL NECK OF HUMERUS (LATERAL)
What structures run through the triangular space (upper extremity)?
Circumflex scapular artery and veins
(no nerve)
What are boundaries of triangular space?
Teres minor
Teres major
Long head of triceps (lateral)
What structures run through the triangular interval (upper extremity)?
Radial nerve
Profunda brachii artery
What are boundaries of triangular interval (upper extremity)?
Teres major
Long head of triceps (Medial)
Lateral head of triceps (Lateral)
Mild Shoulder Separation-what is affected?
Acromioclavicular ligament severed
Severe Shoulder Separation-what is affected?
Both acromioclavicular ligament and coracoclavicular ligaments severed
What happens in Shoulder Dislocation?
Humeral head out of socket
What should you test if you suspect shoulder dislocation?
Test nerve sensation of axillary nerves and musculocutaneous nerves
Which direction is the humerus most commonly displaced out of glenoid cavity?
Anterior (95%)
What causes shoulder dislocation?
Aggressive abduction and lateral rotation that damages or stretches rotator cuff
*baseball
What things can get damaged in shoulder dislocation and why?
Damage to axillary nerve can occur due to close relation to inferior part of the joint capsule
Can also damage axillary artery and vein and brachial plexus
Anterior shoulder dislocation appears?
Arm typically held in external rotation and slight abduction
Posterior shoulder dislocation appears?
Arm typically held in adduction and internally rotated
Fractures of the surgical neck of humerus are common in what population?
elderly with osteoporosis
INJURY TO SURGICAL NECK OF HUMERUS USUALLY RESULTS IN DAMAGE TO?
AXILLARY NERVE
Damage to the surgical neck of humerus that results in damage to axillary nerve results in ?
Numbness and loss of sensation over the shoulder and inability to abduct the arm to 90 degrees
Transverse fractures of humerus are usually classified as?
Spiral fractures
FRACTURE AT THE HUMERAL SHAFT MAY DAMAGE WHAT NERVE?
RADIAL NERVE
What is the main symptom of radial nerve damage?
Wrist drop
When drawing blood from medial cubital vein, must be careful to not puncture?
biceps tendon, brachial artery, median nerve
*if use cephalic or basilic vein instead-no worries, only muscle underneath
INJURY TO DISTAL HUMERUS MAY DAMAGE WHAT NERVE?
MEDIAN NERVE
INJURY TO MEDIAL EPICONDYLE OF HUMERUS MAY DAMAGE WHAT NERVE?
ULNAR NERVE
WHAT CAN CAUSE WINGED SCAPULA?
THE LONG THORACIC NERVE ARISES FROM C5, C6, C7 NERVE ROOTS. IF THE ROOTS OR THE LONG THORACIC NERVE ITSELF IS DAMAGED, THE SERRATUS ANTERIOR WILL BE PARALYZED
WHAT ARE THE SIGNS OF WINGED SCAPULA?
ARM CAN’T BE ABDUCTED ABOVE 90 DEGREES
SCAPULA MOVES LATERALLY AND POSTERIORLY
Rotator cuff syndrome results in?
Shoulder pain induced by movement of the humerus that steadily worsens over time
Instability in the glenohumeral joint
Degenerative tendinitis and/or rupture of the supraspinatus tendon (most common injury)
Why should you never push down on a broken clavicle?
Axillary artery/vein and cords of brachial plexus run underneath the clavicle
WHICH MUSCLES OF THE UPPER EXTREMITY ARE LATERAL ROTATORS
POSTERIOR DELTOID
INFRASPINATUS
TERES MINOR
WHICH MUSCLES OF THE UPPER EXTREMITY ARE MEDIAL ROTATORS?
SUBSCAPULARIS
TERES MAJOR
ANTERIOR DELTOID
PECTORALIS MAJOR
LATISSIMUS DORSI
What nerve innervates deltoid?
axillary nerve
What is the primary action of anterior deltoid?
flexes and medially rotates
What is the primary action of medial deltoid?
Power abductor of arm starting from 15 to 90 degrees
What is the primary action of the posterior deltoid
extends and laterally rotates
What nerve innervates supraspinatous?
Suprascapular nerve
What is the primary action of supraspinatous
initiates abduction of arm up to 15 degrees (then the deltoid kicks in )
What is the primary action of teres major and also latissimus dorsi?
adducts, extends, and medially rotate
What innervates pectoralis major?
Lateral and medial pectoral nerve
What is the primary action of pectoralis major?
adducts, flexes, and medially rotates
If a football player gets hit on the side wall of chest, what injury should you worry about?
Damage to the long thoracic nerve.
This paralyzes serratus anterior and results in winged scapula since serratus anterior can no longer hold shoulder in