2.10 scapular area and shoulder

Question 1

give the nerve, blood supply and action of the following- refer to slide5

1. trapezius
2. rhoboideus minor/major
3. latissimus dorsi
4. levator scapulae

Answer 1

Trapezius and deltoid attached to the acromion and contract in opposing directions. Deep to the trapexius the scapula is attached to the vertbral columns by levator scapulae, rhomboid minor/major, which work with the deltoid and trapezius to position the scapula

1. trapezius - attaches the scapula and clavicle to the trunk
   
   1. nerve
      
      1. motor accesory nerve (XI)
      2. sensory via anterior rami of C3-4
   2. blood supply
      
      1. superficial branch of the transverse cervical artery
   3. function
      
      1. powerful elevator of scapula
         
         1. rotates the scapula during abduction of humerus above horizontal
      2. middle fibers
         
         1. retract scapula
      3. lower fibers
         
         1. depress scapula
2. deltoid
   
   1. nerve
      
      1. Axillary Nerve(C5-C6)
   2. blood supply
   3. action
      
      1. major abductor of arm
         
         1. abducts arm beyond initial 15degress done by supraspinatus
      2. clavicular fibers
         
         1. assist in flexing the arm
      3. posterior fibers
         
         1. assist in extending the arm
3. levator scapulae
   
   1. nerve
      
      1. dorsal scapular nerve
      2. branches from anterior rami of C4-3
   2. action
      
      1. elevates the scapula
4. rhomboid minor/major
   
   1. nerve
      
      1. dorsal scapular nerve
   2. action
      
      1. elevates and retracts the scapula

Question 2

What is this patient presenting with?

1. note the displacement

Answer 2

clavicle fracture

1. presentation
   
   1. arm usually frops and pulled medially from gravity and pec major
   2. displacement of proximal clavicle is pulled down and medially into the muscle
2. cause
   
   1. mechanism
      
      1. fall onto shoulder or outstretched arm
   2. clavicle is small with large forces acting on it to tramsit from the upper limb to the trunk.
   3. typical fracture site is the middle third, proximal to the attachment or the coracoclavicular ligament
3. treatment
   
   1. clean
      
      1. immobilization
   2. complicated
      
      1. requires surgery

Question 3

list this joint type, ligaments, motions and muscles

Answer 3

sternoclavicular joint

1. synovial joint with articular disc
   
   1. surrounded by joint capsule
2. ligament-4 reinforce the joint capsule
   
   1. interclavicular ligament
      
      1. links the ends of the two clavicles to each other and to the superior surface of the manubrium of sternum
   2. anterior sternoclavicular ligament
   3. posterior sternoclavicular ligament
   4. costaclavicular ligament
      
      1. positioned laterally to the joint and links the proximal end of the clavicle to the first rib and related costal cartilage
3. motions
   
   1. predominantly in the anteroposterior and vertical planes
   2. some rotation
4. muscles
   
   1. no muscle crosses the joint

Question 4

Answer 4

Question 5

what are the joints acting on the shoulder?

Question 6

discuss the joint type, ligaments (location and function), motions, muslces,

which AC ligament provides most of the integrity/strength?

Answer 6

acromioclavicular joint (AC)

1. synovial joint
   
   1. surrounded by a joint capsule
2. ligaments- 3
   
   1. acromioclavicular ligament
      
      1. superior to the joint and passing between adjacent regions of the clavicle and acromion
   2. coracoclavicular ligaments- Spans the distance between the coracoid process of the scapula and the inferior surface of the acromial end of the clavicle.
      
      1. trapezoid ligament
         
         1. attaches trapezoid line on the clavicle
      2. conoid ligament
         
         1. attaches to the related coniod tubrecle
      3. aside
         
         1. not directly related to the joint (strong accesory ligament) providing musch of the weight-bearing support for the upper limb on the clavicle and maintaining the position of the clavicle on the acromion
3. motions
   
   1. anteroposterior and vertical planes
   2. some slight axial rotation
4. muscles
   
   1. no muscles “crosses” the jiont and acts on it
      
      1. the trapezius does not act on the joint, even though it manipulates the scapula alot

coracoclavicular ligaments provide most of the integrity/strength of the AC joint

Question 7

a person presents with this in the er. Discuss the cause, pathology and grades.

Answer 7

shoulder seperation

1. cause
   
   1. the AC joint is relatively weak to allow for mobility
      
      1. coracoclavicular ligaments provide most of the strength
   2. damage to acromioclavicular ligament and/or coracoclavicular ligaments
2. pathology
   
   1. weight of upper limb pulls scapula and acromion inferiorly below clavicle
      
      1. clavicle overrides acromion (piano key sign)
3. shoulder seperation grades
   
   1. partially stretched AC ligaments
      
      1. coracoclavicular ligaments intact
   2. torn AC ligament with some displacement
      
      1. coracoclavicular ligaments intact
   3. complete seperation of jiont.
      
      1. acromioclavicular and coracoclavicular ligaments are torn
   4. grades 4-6 uncommon

Question 8

describe the type of joint., location, and structures.

Answer 8

Glenohymeral Joint

1. location
   
   1. synovial ball and socket articulation between the head of the humerus and the glenoid cavity of the scapula.
   2. multiaxial with wide range at the cost of stability.
      
      1. stability is povided by
         
         1. rotor cuff
         2. long head of biceps brachii
         3. bony processes
         4. extrascapular ligaments
2. structure
   
   1. glenoid labrum
      
      1. fibrocartilagenous collar
      2. “deepens” glenoid cavity
      3. creates a vaccum effect
      4. w/o labrum, glenohumeral stability decreases by 20%
   2. capsule
      
      1. attaches from glenoid cavity to anatomical neck of humerus
      2. least amount of support inferioly
   3. ligaments
      
      1. coracocromial
         
         1. ​helps resist upward displacement of the head of the hymerus
      2. coracohumeral
         
         1. strengthens superior portion of capsule
         2. some support during shoulder abduction
      3. transverse humeral
         
         1. ​holds long head of bicps in the groove
      4. glenohumeral
         
         1. ​3 parts all attach from upper margin of glenoid cavity and strengthen anterior protion of capsule
            
            1. superior, middle and inferior

Question 9

discuss the movments

which joint allows for this movment?

Answer 9

glenohumeral-main source of these

atalantoaxial

stewrnoclavicular

Question 10

describe the ligaments of the glenohumeral cavity

Answer 10

1. coracocromial
   
   1. ​helps resist upward displacement of the head of the hymerus
2. coracohumeral
   
   1. strengthens superior portion of capsule
      
      1. some support during shoulder abduction
3. transverse humeral
   
   1. ​holds long head of bicps in the groove
4. glenohumeral​
   
   1. 3 parts all attach from upper margin of glenoid cavity and strengthen anterior protion of capsule
      
      1. superior, middle and inferior

Question 11

describe the anterior axioappendicular muscle

attachment, structures, innervation and motion

Answer 11

anterior axioappendicular muscles

pectoralis major

1. constituents-attachements
   
   1. clavicular head
      
      1. origin
         
         1. anteriorsurface of medial half of clavicle; sternocostal head
      2. insertion
         
         1. lateral lip of intertubercular sulcus
   2. sternocostal head
      
      1. origin
         
         1. anterior surface of the sternum. first 7 costal cartilages-external oblique
      2. insertion
         
         1. lateral lip of intertubercular sulcus of humerus
2. innervation
   
   1. lateral/medial pectoral nerves
3. motin
   
   1. adducts
   2. medial rotation
   3. flex humerus
   4. scapula protraction

Question 12

describe the axioappendicular muscle attachment, structures, innervation and motion

Answer 12

pectoralis minor

1. attachment
   
   1. attaches to coracoid process from ribs
2. innervation
   
   1. medial pectoral nerve
3. motion
   
   1. satabilizes scapula against thoracic wall (anterior/inferior)

Question 13

define the structure attachment, innervation and motion

Answer 13

anterior axioappendicular muscles

1. attachment
   
   1. attaches clavicle to first rib
2. innervation
   
   1. subclavian nerve
3. motion
   
   1. depresses scapula

Question 14

define the structure, attachments, innervation, blood vessel, and motion

Answer 14

anterior serratus of the anterior axioappendicular muscles

1. attachment
   
   1. origin
      
      1. lateral surfaces of upper 8-9 ribs
   2. insertion
      
      1. costal surface of medial c=border of scapula
2. innervation
   
   1. long thoracic (C5-C7)
3. movement
   
   1. protraction
   2. rotation of scapula

Question 15

discuss the muscle innervation, blood supply, action and fibers

Answer 15

deltoid

1. deltoid
   
   1. nerve
      
      1. Axillary Nerve(C5-C6)
   2. blood supply
   3. action-attaches scapula and calvicle to the humerus
      
      1. major abductor of arm
      2. abducts arm beyond initial 15degress done by supraspinatus
   4. clavicular fibers
      
      1. assist in flexing the arm
   5. posterior fibers
      
      1. assist in extending the arm

Question 16

What is the name, innercation, origin, insertion, and function of this muscle

Answer 16

subscapularis- on the anterior scapular side (sits between the thoracic wall and the scapula)

1. attachment
   
   1. origin
      
      1. subscapular fossa
   2. insertion
      
      1. the lesser tubercle of the humerus
2. innervation
   
   1. upper and lower subscapular nerves
3. action
   
   1. medially rotates the humerus and helps stabilize its head in the glenoid cavity

stabilzes the glenohumeral cavity along with supra/infrspinatus and teres minor

Question 17

discuss this area, muscles, innervation, attachment, blood supply and action

Answer 17

posterior scapular muscles

1. supraspinatus
   
   1. nerve
      
      1. suprascapular nerve
   2. attachment
      
      1. pathway
         
         1. passes beneath the acromion and acromioclavicular ligament
      2. origin
         
         1. medial 2/3 of supraspinous fossa
      3. insertion
         
         1. superior facet on the greater tubercle of humers
   3. blood supply
   4. action-at the glenohumeral joint
      
      1. rotator cuff muscle
      2. initiate arm abduction to 15 degrees
2. infraspinatus
   
   1. nerve
      
      1. suprascapular nerve (C5-C6)
   2. attachment
      
      1. origin
         
         1. medial 2/3 of infraspinous fossa of the scapula
      2. insertion
         
         1. middle facet on posterior surface of greater
         2. tubercle of the humerus
   3. blood supply
   4. action
      
      1. rotator cuff muscle
      2. lateral rotation of arm at the glenohumeral joint

both of these are involved with stabilizing the glenohumeral joint along with the teres minor and the subscapularis.

Question 18

list muscles nerves, attachment, blood supply and motion

Answer 18

posterior scapular muscles

1. teres minor
   
   1. nerve
      
      1. axillary nerve (C5-C6)
   2. attachments
      
      1. origin
         
         1. upper 2/3 of a flattened strip of bone on theposterior surface of the scapula immediatly adjacent to the lateral border of the scapula
      2. insertion
         
         1. inferior facet on the posterior surface of thegreater tubercle of thehumerus
   3. blood supply
   4. motion
      
      1. rotaor cuff muscle; lateral rotation of arm at the glenohumeral joint
2. teres major
   
   1. nerve
      
      1. inferior subscapular nerve (C5-C7)
   2. attachment
      
      1. origin
         
         1. elongate oval area on the posterior surface of the inferior angle of the scapula
      2. insertion
         
         1. medial lip of the intertuvercular sulcus on the anterior surface of the humerus
   3. blood supply
   4. motion
      
      1. medial rotation and extension of arm at the glenohumeral joint
      2. stabilizes the glenohumeral joint, along with the supra/infraspinatus and the subscapularis

Question 19

list muscle, nerve, attachment, blood supply and motion

Answer 19

long head of triceps brachii

1. nerve
   
   1. radial nerve (C6-C8)
2. attachment
   
   1. origin
      
      1. infraglenoid tubercle on scapula
   2. insertion
      
      1. common tendon of insertion with medial and lateral heads on the olecranon process of ulna
3. blood supply
4. motion
   
   1. extension of the forarm at the elbow; axxesory adductor and extensor of the arm at the glenohumeral joint

the importance of the triceps brachii in the posterior scapular region is that its vertical course between the teres minor and teres major, together with these muscles and the humerus, forms spaces through which nerves and vessels pass between regions

Question 20

describe stabilizing components of the glomerohumeral joint. Define the motion of each muscle involved. What is left vulnerable in this joint?

Answer 20

stability of the glenohumeral joint

protective circle of muscular tendons

1. structure
   
   1. rotator cuff is generated by four muscles’ tendons that fuse with the capsule of the should joint reinforcing it, except inferiorly
2. all the muscles insert around the glenohumeral joint to generate the rotator cuff. alone each muscle has a specific action
   
   1. supraspinatus
      
      1. initiates the first 15 degree of abductionat GH
   2. infraspinatus
      
      1. lateral rotation at GH
   3. teres minor
      
      1. lateral rotatin at GH
   4. subscapularis
      
      1. medially rotate humerus at GH
3. rotator cuff purpose
   
   1. stabilize GH joint to allow wide range of motion

Question 21

a patient presents with this appearance. what is his condition, cause, special conditions that maya have led to this. What about nervous damage?

Answer 21

shoulder dislocation

1. anteroinferior dislocation
2. cause
   
   1. glenohumeral joint is most suseptible to dislocations when arm is
      
      1. abducted and externally rotated
         
         1. ​this put the head of the humerus facing inferiorly and no muscles to protect it from tearing through the ligements on the inferior side
      2. once out of the glenoid cavity, the powerful pec major puto lls the humerus anterosuperioly
         
         1. this is due its position
   2. usually associated with an isolated trauma but
      
      1. inferior portion of glenoid labrum could be torn by bony fragment and/or cartilage disrupted allow for frequent dislocations.
3. axillary nerve damage may aoccur
   
   1. may be damaged from compression
      
      1. as it passes through the quadrangular space
4. lengthening of the radial nerve
   
   1. tightly bound to the radial groove, when stretched may lead to radial nerve paralysis

Question 22

explain a rotator cuff disorder from a tennis player of 40 + years, who presents with a popeye deformity

Answer 22

impingment syndrome

1. condition
   
   1. supraspinatus passes beneath the acromion and the acromioclavicular ligament. This fixed dimension, space between the tendon and supraspinatus, contains a bursa sac to reduce the friction.
   2. When the arm is abducted, the humeral head ‘pinches’ structures under the coracoacromial ligament
      
      1. structures affected
         
         1. supraspinatus
         2. subacromial bursa
         3. tendon of long head brachii
   3. produce significant impingment when the arm is abducted
      
      1. swelling of the supraspinatus muscle
      2. excessive fluid with in the subacromial/subdeltoid bursa
      3. subacromial boy spurs
2. disorder
   
   1. degradative
      
      1. tendonitis
      2. bursitis
   2. rupture of biceps tendon
3. presentation
   
   1. inability to abduct arm
   2. popeye deformity-rupture of biceps brachii

Question 23

A patient does not attend physical therapy or take his antiinflammatory medication after a shoulder operation. what is this person susceptible to? list condition, cause, who is more susceptible to this, presentation and treatment.

Answer 23

frozen shoulder

1. cause
   
   1. injury to jiont capsule
   2. seen more in patients with
      
      1. diabetes
      2. chronic inflammatory arthritis
2. presentation
   
   1. significant range of motion
   2. inflammatinon, scarring, thickening, and shrinkage of the capsule that surround the joint
3. treatment
   
   1. requires aggressive combination of anti-inflammatories and physical therapy
      
      1. w/o aggressive treatment a frozen shoulder can be permanent