Shoulder joint bones

Question 1

bones and joints in the shoulder joint

Answer 1

scapula and humerus, glenohumeral joint

Question 2

what is the humerus

Answer 2

a long bone, the largest in upper limb, proximal end, rounded- like a hemisphere
articulates with scapula
shaft of humerus
distal end- flattened, widened, tilted forward, 3 fossae, articulates with radius and ulna

Question 3

proximal bony features of humerus

Answer 3

head, anatomical neck (articular surfaces meet non articular surface), greater tubercle, lesser tubercle, intertubercular sulcus (bicipital groove)- allows passage of long head of biceps
surgical neck

Question 4

what is the importance of the surgical neck

Answer 4

area of body if you fall on outstretched hand (FOOH)- injury or fracture to this area

Question 5

midshaft bony points of humerus

Answer 5

deltoid tuberosity- insertion of deltoid muscles
spiral groove (radial)- inferior to deltoid tuberosity- indicates passage of radial nerve

Question 6

distal bony points of humerus

Answer 6

medial and lateral supracondylar ridge, medial and lateral epicondyle, trochlea, capitulum, coronoid fossa, radial fossa, olecranon fossa

Question 7

articular surfaces for glenohumeral joint

Answer 7

covered in hyaline cartilage, humeral head larger than glenoid fossa, glenoid labrum, surrounded by joint capsule and nourished by synovial fluid

Question 8

what does the glenoid labrum do

Answer 8

fibrocartilaginous rim that deepens glenoid fossa

Question 9

joint line of glenohumeral joint

Answer 9

in line anteriorly with tip of coracoid process and inferior to acromion, in concave fossa

Question 10

classification of the glenohumeral joint

Answer 10

a synovial, multiaxial ball and socket joint with 3 degrees of motion (flex, ext, adb,add, MR, LR, circumduction

Question 11

glenohumeral joint capsule

Answer 11

loosely surrounded has an inferior fold, strengthened by ligaments and tendons of the rotator cuff muscles, strengthened by rotator cuff muscles- supported head of humerus in shallow
glenoid and limit movements

Question 12

glenohumeral joint synovial membrane

Answer 12

lines capsule, communicating and 3 bursae, subacromial and subdeltoid and subcoracoid bursae- prevent friction

Question 13

glenohumeral joint capsular ligaments

Answer 13

superior, middle, inferior, transverse glenohumeral

Question 14

what does the transverse glenohumeral ligament do

Answer 14

holds bicep tendon as it travels and wraps around the supra glenal tubercle- has synovial sheath which it moves within to prevent friction between itself and floor of bicipital groove

Question 15

glenohumeral joint accessory ligaments

Answer 15

coracoacromial and coracohumeral ligament (from coracoid process to greater tubercle of humerus)

Question 16

what causes shoulder instability

Answer 16

shall glenoid fossa, large head of humerus, loose articular capsule

Question 17

solutions to shoulder instability

Answer 17

glenoid labrum, ligaments, rotator cuff muscles

Question 18

how to the rotator cuff muscles support joint stability

Answer 18

tendons of supraspinatus, infraspinatus, teres minor and subscapularis- tendons of muscles join up (circumferential cuff)- has muscular element to it, meaning there is control in each of these elements as muscle is voluntary/ involuntary control to maintain control of head of humerus within shallow glenoid fossa

Question 19

common pathologies- dislocation

Answer 19

anterior (usually from a fall) and posterior dislocation (usually comes about due to electrocution), an anterior dislocation is where the head of humerus comes out of the glenoid and can put pressure on/damage axillary nerve

Question 20

common pathologies- fractured neck

Answer 20

fractured neck of humerus- through surgical neck- 1,2,3, part fractures

Question 21

common pathologies- frozen shoulder

Answer 21

adhesive capsulitis- capsule become less mobile- becomes stiff and unable to move in normal fluidity, this thickening effects capsule in its entirety- and have capsular pattern of reduced mobility

Question 22

frozen shoulder fazes

Answer 22

goes through several phases- can come on without environmental trigger or with environmental trigger

Question 23

glenohumeral joint accessory movements- AP

Answer 23

an anterior posterior movement is produced by leaning through your arm onto your thenar eminence

Question 24

glenohumeral joint accessory movements- PA

Answer 24

place your two thumb tips in contact with the posterior surface of the head of humerus, lift the head of humerus in a posteroanterior direction

Question 25

glenohumeral joint accessory movements- longitudinal

Answer 25

facing the head of the bed, movement is produced by pressure in a caudal direction against the models forearm, when the elbow is flexed to 90°

Question 26

glenohumeral joint accessory movements- lateral

Answer 26

one hand lateral at the elbow, one hand medially at the axilla, movement is produced by the medial hand pushing out against the inwardly stabilizing effect of the lateral hand