Upper Limb: Shoulder Region Flashcards
Which fossa is found on the costal surface of the scapula?
A. Supraspinous fossa
B. Infraspinous fossa
C. Subscapular fossa
C
Which border of the scapula is located in close proximity to the vertebral column?
Medial border (vertebral border)
Which bone prominence (projection) is located on the posterior aspect of the scapula?
A. Spine of scapula
B. Acromion process
C. Coracoid process
A
Which of the following is a bony landmark of the proximal humerus? Select all that apply.
Inferior angle
Greater tubercle
Lesser tubercle
Spinoglenoid notch
Surgical neck
Greater tubercle
Lesser tubercle
Surgical neck
The acromioclavicular joint is formed by the articulation of which two structures?
The acromial end of the clavicle and the acromion process of the scapula
Which ligament prevents the scapula from being displaced medially beneath the clavicle?
A. Coracohumeral
B. Acromioclavicular
C. Coracoacromial
D. Coracoclavicular
D
True or false: The glenohumeral joint is a ball and socket joint that allows two degrees of freedom (flexion/extension, adduction/abduction).
False
What structures form the coraco-acromial arch? Select all that apply.
Deltoid
Acromion process
Coracoid process
Coracohumeral ligament
Coracoacromial ligament
Acromion process
Coracoid process
Coracoacromial ligament
Which structure serves to deepen the glenoid cavity?
Glenoid labrum
Which of the following ligaments converts the intertubercular sulcus into a canal?
A. Coracohumeral
B. Transverse humeral
C. Glenohumeral
B
What is the functional significance of the three segments of the upper limb?
Proximal segment: Places the hand in space
Intermediate segment: Positions the hand
Terminal segment: Manipulation of the environment
What bones form the skeleton of the upper limb?
Clavicle
Scapula
Humerus
Radius
Ulna
Carpals
Metacarpals
Phalanges
What is the major joint found in the upper limb?
Synovial joint
The scapulothoracic joint is the only joint of the upper limb that is NOT a synovial joint—or a TRUE joint for that matter. What type of joint is it, and why is it not a true joint?
Physiological joint
Bones are not articulating; the scapula glides across the muscles below it.
What is the name of the structure that gives rise to the multi-segmental peripheral nerves that supply the upper limb?
Brachial plexus
What is the name of the artery that supplies the majority of the upper limb with blood?
Axillary artery
Let’s talk about the brachial plexus.
- How many roots are there? Where do they originate?
- How many trunks are there?
- How many divisions?
- How many cords?
- 5 roots originating from the anterior rami of C5-T5
- 3 trunks (superior, middle, inferior)
- 6 divisions (3 anterior, 3 posterior)
- 3 cords (lateral, medial, posterior)
5.
What are the dermatomes of the upper limb? Label the yellow highlights.
See image
Key landmarks:
- Thumb: C6
- Pinky: C8
- Armpit: T1
What is the origin for the supraspinatus?
Supraspinous fossa
What is the origin for the infraspinatus?
Infraspinous fossa
What is important about the greater tubercle of the humerus?
It is a point of attachment for 3 of 4 rotator cuff muscles
What are the 4 joints of the shoulder region?
Acromioclavicular
Sternoclavicular
Glenohumeral
Scapulathoracic
Why is the scapulothoracic joint a joint of the shoulder region?
You can’t have overhead motion without the scapula gliding out superolaterally
What is the difference between a glenohumeral subluxation and glenohumeral dislocation?
Subluxation: Changes relation of humeral head to glenoid fossa but humeral head is not completely out of the glenoid fossa
Dislocation: humeral head completely out of glenoid fossa
What are the primary myotomes of the upper limb and their corresponding spinal nerves?
- C5: shoulder abduction
- C5, C6: elbow flexion
- C7: Elbow extension, wrist extension, finger extension
- C8: wrist flexion, finger flexion
- T1: Intrinsic muscles
What are the names of the bones of the shoulder region?
Clavicle
Scapula
Humerus
Which joint serves as the only bony link between the axial and superior appendicular skeleton?
Sternoclavicular joint
What ligament is important for preventing downward displacement of the scapula?
Coracoclavicular ligament
Which bones articulate to form the glenohumeral joint?
Glenoid fossa of scapula and humeral head
What structures form an arch over the glenohumeral joint?
Acromion, coracoid process, and coraco-acromial ligament
What is the name of the bursa that protects the supraspinatus tendon from the coraco-acromial arch?
Subacromial bursa
Label the bony landmarks of the clavicle.
See image
Label the bony landmarks of the scapula (anterior and posterior view).
See image
Label the bony landmarks of the scapula (superior and lateral view).
See image
Label the bony landmarks of the humerus.
See image
What are the articulations within the sternoclavicular joint?
Sternal end of clavicle, clavicular notch of the manubrium
What 3 ligaments are associated with the SC joint?
Anterior and posterior sternoclavicular ligaments
Costoclavicular ligament
Interclavicular ligament
What movements occur at the SC joint?
Elevation, depression, anterior/posterior gliding, rotation
What is unique about the SC joint in relation to the synovial cavity?
There are TWO synovial cavities separated by an articular disc allowing the joint to move freely (similar to a ball and socket joint)
What are the articulations of the acromioclavicular joint?
Acromial end of clavicle with acromion process of scapula
What ligaments are associated with the AC joint?
Acromioclavicular
Coracoclavicular (conoid and trapezoid)
What movements occur at the AC joint?
Rotation during movements of the scapula
What are the articulations of the glenohumeral joint?
humeral head and glenoid cavity (fossa) of scapula
What is the purpose of the glenoid labrum?
Deepen the cavity of the glenoid fossa
What are the ligaments associated with the GH joint?
Coracohumeral
Glenohumeral (superior, middle, inferior)
Transverse humeral
What are the two bursae associated with the GH joint?
Subacromial (most important to remember)
Subscapular
What movements occur at the GH joint?
Flexion and extension
Adduction and abduction
Internal and external rotation
What are the “articulations” of the scapulothoracic joint?
Scapula and thoracic wall (subscapularis and serratus anterior)
What movements occur at the ST joint?
Elevation and depression
Retraction and protraction
Upward rotation and downward rotation
What is adhesive capsulitis or frozen shoulder?
Inflammation causes a thickening and stiffening of the GH joint capsule and ligaments resulting in pain and decreased mobility of the shoulder.
Which of the following muscles can be easily palpate lateral to the sternum and inferior to the clavicle?
A. Trapezius
B. Pectoralis major
C. Deltoid
B
True or false: The posterior axillary fold is formed by the teres major and the tendon of the latissimus dorsi.
True
What structures form the boundary of the clavipectoral triangle? Select all that apply:
Clavicular portion of the pectoralis major muscle
Trapezius
Deltoid
Clavicle
Sternum
Clavicular portion of the pectoralis major muscle
Deltoid
Clavicle
Which of the following muscles is a muscle of the anterior axio-appendicular group of muscles? Select all that apply.
Rhomboids
Serratus anterior
Trapezius
Pectoralis minor
Deltoid
Subclavius
Serratus anterior
Pectoralis minor
Subclavius
Which of the following muscles will have its action on the humerus?
A. Pectoralis minor
B. Teres major
C. Rhomboids
D. Serratus anterior
A
Which of the following inserts on the lateral lip of the intertubercular sulcus?
A. Pectoralis major
B. Pectoralis minor
C. Subclavius
D. Serratus anterior
A
Which of the following muscles has an origin point on the rib cage? Select all that apply.
Serratus anterior
Subclavius
Pectoralis major
Pectoralis minor
All of them!
Serratus anterior
Subclavius
Pectoralis major
Pectoralis minor
Which of the following muscles will contribute to upward rotation of the scapula?
A. Serratus anterior
B. Pectoralis major
C. Subclavius
A
Which of the following muscles has its insertion on the clavicle, and the acromion process and spine of the scapula?
A. Latissimus dorsi
B. Rhomboids
C. Trapezius
C. Levator scapulae
C
Which of the following muscles originates from the spinous processes of either the cervical and/or thoracic vertebrae? Select all that apply.
Latissimus dorsi
Levator scapulae
Trapezius
Rhomboids
Latissimus dorsi
Trapezius
Rhomboids
Which of the following muscles will adduct, internally (medially) rotate, and extend the humerus of the GH joint?
A. Trapezius
B. Latissimus dorsi
C. Rhomboids
D. Levator scapulae
B
Which of the following muscles has an origin point from the clavicle and the acrimion process and spine of the scapula?
A. Deltoid
B. Supraspinatus
C. Infraspinatus
D. Subscapularis
A
Which of the following muscles is considered a muscle of the rotator cuff? Select all that apply.
Teres major
Teres minor
Deltoid
Supraspinatus
Infraspinatus
Subscapularis
Teres minor
Supraspinatus
Infraspinatus
Subscapularis
Which of the following muscles insert onto the greater tubercle of the humerus? Select all that apply.
Teres major
Teres minor
Deltoid
Supraspinatus
Infraspinatus
Subscapularis
Teres minor
Supraspinatus
Infraspinatus
Which of the following muscles produces abduction, flexion, and extension of the humerus at the GH joint?
A. Teres minor
B. Deltoid
C. Teres major
D. Supraspinatus
B
Which of the following structures forms the quadrangular space? Select all that apply.
Teres minor
Teres major
Lateral head of triceps
Long head of triceps
Surgical neck of humerus
Teres minor
Teres major
Long head of triceps
Surgical neck of humerus
Which structure forms the lateral boundary of the triangular space?
Long head of triceps
Which structures can be seen in the quadrangular space? Select all that apply.
Radial nerve
Posterior circumflex humeral artery
Circumflex scapular artery
Axillary nerve
Profunda brachii artery
Posterior circumflex humeral artery
Axillary nerve
Which structures form boundaries of the apex of the cervical-axillary canal?
Clavicle, 1st rib, superior edge of scapula
Which structure forms the lateral wall of the axilla?
Proximal humerus (at level of intertubercular sulcus)
True or false: Neurovascular structures traveling between the neck and upper limb travel through the cervical-axillary canal.
True
Which muscle of the shoulder region is the ONLY muscle that is NOT innervated by branches of the brachial plexus? What is it innervated by?
Trapezius
CN XI (Spinal Accessory Nerve)
Which of the following branches of the brachial plexus supplies the serratus anterior?
A. Long thoracic nerve
B. Thoracodorsal nerve
C. Lateral pectoral nerve
D. Medial pectoral nerve
A
Which never innervates both the supraspinatus and infraspinatus?
Suprascapular
True or false: The blood supply to the muscles of the shoulder region arise from branches of the subclavian and axillary arteries.
True
Which of the following arteries are branches of the thoracoacromial artery? Select all that apply.
Clavicular
Lateral thoracic
Subscapular
Pectoral
Acromial
Deltoid
Clavicular
Pectoral
Acromial
Deltoid
Which of the following arteries supply the humeral head and GH joint with blood?
A. Anterior and posterior circumflex humeral arteries
B. Thoracodorsal and lateral thoracic arteries
C. Circumflex scapular and suprascapular arteries
A
Which of the following arteries network together to form anastomoses around the scapula? Select all that apply.
Lateral thoracic
Dorsal scapular
Suprascapular
Circumflex scapular
Thoracodorsal
Dorsal scapular
Suprascapular
Circumflex scapular
Which artery is vulnerable to damage secondary to a fracture of the surgical neck of the humerus?
Posterior circumflex humeral
What structures form the boundaries of the cervico-axillary canal?
First rib, scapula, superior edge of scapula
What forms the apex of the axilla?
Cervico-axillary canal
The subscapularis, teres major, and latissimus dorsi form which wall of the axilla?
Posterior
What do the suprascapular and nerve to subclavius have in common?
Both originate from ventral rami of C5 and C6
Which suprascapular nerve originates from only one spinal root?
Dorsal scapular nerve
Which nerve root originates from 3 spinal nerves and before the trunks of the brachial plexus?
Long thoracic nerve
Which muscle of the upper limb is innervated by a nerve DIFFERENT than the brachial plexus? What nerve innervates it?
Trapezius
CN IX (accessory)
How many suprascapular nerves are there? What are their names and origins?
- Dorsal scapular (ventral ramus, C5)
- Long thoracic nerve (ventral rami, C5, C6, C7)
- Supraclavicular nerve (C5, C6 —> superior trunk)
- Nerve to subclavius (C5-C6 —>superior trunk)
How many infraclavicular branches are there?
6
How many TERMINAL branches originate from the posterior cord of the brachial plexus and what are their names?
2
Axillary nerve
Radial nerve
How many NONTERMINAL branches originate from the posterior cord? What are their names?
3
Upper subscapular
Lower subscapular
Thoracodorsal
The intercostal brachial nerve originates from which spinal nerve? What does it supply?
T2; Axilla
Which artery supplies the rhomboids, levator scapulae and trapezius and contributes to scapular anastomoses?
Dorsal scapular artery
True or false: The thoracoacromial artery has 2 branches.
False; it has 4!
Clavicular, pectoral, acromial, deltoid
True or false: The subscapular artery has 2 branches.
True!
Thoracodorsal, circumflex scapular
What structure/s does the circumflex humeral artery supply?
Anterior and posterior head of humerus and glenohumeral joint
The _____________ artery supplies teres major and minor and contributes to blood supply to the entire rotator cuff vis anastomoses.
Circumflex scapular
Which of the following arteries form anastomoses around the scapula?
Thoracodorsal
Dorsal scapular
Thoracoacromial
Suprascapular
Circumflex scapular
Circumflex humeral
Dorsal scapular
Suprascapular
Circumflex scapular
NOTE: The circumflex humeral artery DOES anastomose, but it does so around the GH joint, NOT the scapula!
True or false: the scapulohumeral muscles of the shoulder region can be divided into anterior and posterior groups.
FALSE
The axio-appendicular muscles are divided into anterior and posterior groups
What four muscles are found in the anterior axio-appendicular shoulder region? What do they act on? What nerve/s innervate them?
Subclavius: acts on clavicle; innervated by nerve to subclavius
Serratus anterior: acts on scapula; innervated by long thoracic nerve
Pectoralis major: acts on scapula; innervated by lateral and medial pectoral nerves
Pectoralis minor: acts on humerus; innervated by medial pectoral nerve
True or false: The posterior axio-appendicular muscles of the shoulder region are divided into superficial and deep subgroups.
True
Which posterior axio-appendicular muscles of the shoulder region are superficial? What do they act on? What innervates them?
Trapezius: acts on scapula; innervated by CN XI (accessory nerve)
Latissimus dorsi: acts on humerus; innervated by Thoracodorsal nerve
Which posterior axio-appendicular muscles of the shoulder region are deep? What do they act on? What innervates them?
Levator scapulae: acts on scapula; innervated by dorsal scapular nerves and C3 and C4
Rhomboids: act on scapula; innervated by dorsal scapular nerve
Which of the following scapulohumeral muscles is NOT a muscle of the rotator cuff? Select all that apply.
A. Deltoid
B. Subscapularis
C. Supraspinatus
D. Infraspinatus
E. Teres minor
F. Teres major
A, F
True or false: The muscles of the rotator cuff act on the scapula.
FALSE!
They all ORIGINATE on the scapula, but insert and ACT on the humerus.
What muscle is this? Name its origin, insertion, innervation, and action.
NAME: Pectoralis major
ORIGIN: Clavicular head: anterior surface of medial half of clavicle. Sternocostal head: anterior surface of the sternum and superior 6 costal cartilages. Abdominal head: Aponeurosis of external oblique.
INSERTION: lateral lip of intertubercular sulcus of humerus
INNERVATION: Lateral and medial pectoral nerves
ACTION: Adducts and medial rotates GH joint. Acting alone the clavicular head flexes the shoulder and sternocostal head extends the shoulder from a flexed position.
What muscle is this? Name its origin, insertion, innervation, and action.
NAME: Pectoralis minor
ORIGIN: 3rd to 4th ribs near their costal cartilages
INSERTION: medial border and superior surface of coracoid process of scapula
INNERVATION: medial pectoral nerve
ACTION: stabilizes scapula by drawing it inferiorly and anteriorly against the thoracic wall (protracts scapula)
What muscle is this? Name its origin, insertion, innervation, and action.
NAME: Serratus anterior
ORIGIN: External surfaces of lateral parts of 1st through 8th ribs
INSERTION: Anterior (costal) surface of the medial border of the scapula
INNERVATION: Long thoracic nerve
ACTION: Protracts the scapula and holds it against the thoracic wall; rotates scapula upward
What muscle is this? Name its origin, insertion, innervation, and action.
NAME: Subclavius
ORIGIN: Junction of 1st rib and its costal cartilage
INSERTION: inferior surface of middle 1/3 of clavicle
INNERVATION: Nerve to subclavius
ACTION: Anchors and depresses the clavicle
What muscle is this? Name its origin, insertion, innervation, and action.
NAME: Trapezius
ORIGIN: Medial 1/3 of superior nuchal line; external occipital protuberance, nuchal ligament and spinous processes of the c7-T12 vertebrae
INSERTION: Lateral 1/3 of clavicle, acromion, and spine of the scapula
INNERVATION: CN XI (accessory nerve; motor) and c3 and c4 (pain and proprioception)
ACTION: elevates (superior fibers), depresses (inferior fibers), retracts (middle fibers), and upwardly rotates scapula
What muscle is this? Name its origin, insertion, innervation, and action.
NAME: Latissimus dorsi
ORIGIN: Spinous processes of inferior 6 thoracic vertebrae, thoracolumbar fascia, iliac crest, and inferior 3-4 ribs
INSERTION: Floor of intertubercular sulcus of humerus
INNERVATION: Thoracodorsal nerve
ACTION: extends, adducts, and medially rotates GH joint
What muscle is this? Name its origin, insertion, innervation, and action.
NAME: Levator scapulae
ORIGIN: posterior tubercles of transverse processes of c1-c4 vertebrae
INSERTION: superior part of medial border of scapula
INNERVATION: dorsal scapular nerve (motor) and c3-c4 spinal nerves (pain an proprioception)
ACTION: elevates and downwardly rotates the scapula
What muscle is this? Name its origin, insertion, innervation, and action.
NAME: Rhomboids major (minor not picture; lays superior to major)
ORIGIN: Minor: nuchal ligament and spinous processes of c7-t1 vertebrae. Major: spinous processes of t2-t5 vertebrae
INSERTION: Minor: medial border at level of spine. Major: medial border from spine to inferior angle
INNERVATION: Dorsal scapular nerve
ACTION: Retracts and downwardly rotates scapula; fixes scapula to thoracic wall
What muscle is this? Name its origin, insertion, innervation, and action.
NAME: Deltoid
ORIGIN: lateral 1/3 clavicle, acromion, and spine of scapula
INSERTION: Deltoid tuberosity of humerus
INNERVATION: Axillary nerve
ACTION: Anterior: flexes and medially rotates GH joint. Middle: abducts GH joint. Posterior: Extends and laterally rotates GH joint
What muscle is this? Name its origin, insertion, innervation, and action.
NAME: Subscapularis
ORIGIN: Subscapular fossa
INSERTION: Lesser tubercle of humerus and medial lip of intertubercular sulcus
INNERVATION: Upper and lower subscapular nerves
ACTION: Medially rotates GH joint; helps to hold humeral head in glenoid cavity
What muscle is this? Name its origin, insertion, innervation, and action.
NAME: Supraspinatus
ORIGIN: Supraspinous fossa
INSERTION: Superior facet of greater tubercle of humerus
INNERVATION: Suprascapular nerve
ACTION: initiates and assists deltoid in abduction of GH joint and acts with other rotator cuff muscles to stabilize the shoulder joint
What muscle is this? Name its origin, insertion, innervation, and action.
NAME: Infraspinatus
ORIGIN: Infraspinous fossa
INSERTION: Middle facet of greater tubercle of humerus
INNERVATION: Suprascapular nerve
ACTION: laterally (externally) rotates the GH joint; helps hold humeral had in glenoid cavity of the scapula
What muscle is this? Name its origin, insertion, innervation, and action.
NAME: Teres minor
ORIGIN: superior part (about 2/3s) of the lateral border of the scapula
INSERTION: Inferior facet of greater tubercle of the humerus
INNERVATION: Axillary nerve
ACTION: Laterally (externally) rotates the GH joint; helps hold humeral head in glenoid cavity of scapula
What muscle is this? Name its origin, insertion, innervation, and action.
NAME: Teres major
ORIGIN: Inferior part of the lateral border and dorsal surface of the inferior angle of scapula
INSERTION: medial lip of intertubercular sulcus of humerus
INNERVATION: Lower subscapular nerve
ACTION: abducts and medially rotates the GH joint
The ________ and __________ muscles form a force couple to abduct the humerus.
Supraspinatus
Deltoid
The ________ and __________ muscles together act as lateral rotators of the humerus and prevent translations of the humeral head during overhead arm movements.
Infraspinatus
Teres minor
If the serratus anterior is paralyzed or weak, what happens to the scapula?
“Winging”; the medial border of the scapula will lift off the thorax
If you have an injury to the axillary nerve and experienced paralysis of the deltoid, what would you see?
Loss of rounding of the deltoid and inability to abduct the arm past 15 degrees (that is because supraspinatus imitators abduction but deltoid takes over)
True or false: Teres minor acts alone in external rotation of the shoulder.
False
It works with infraspinatus
True or false: If the suprascapular nerve were injured, you might see paralysis in supraspinatus.
False
You would see paralysis in supraspinatus AND infraspinatus
__________ is the medial rotator of the humerus; coupled with the middle and inferior glenohumeral ligaments, it has been shown to be an important stabilizer of the GH joint, particularly when the arm is held at about a 45 degree abduction.
Subscapularis
