anatomy of the shoulder region

Question 1

What composes the pectoral girdle

Answer 1

Clavicle and scapula

Question 2

What are the skeletal components of the shoulder

Answer 2

pectoral girdle, humerus, 2 joints: glenohumeral and acromioclavicular joint.

Question 3

what are the Ligaments of the shoulder region

Answer 3

coracoclavicular ligaments, coracoacromial ligaments
acromioclavicular ligaments,
glenohumeral (superior/ medial and inferior)

Question 4

Outline the coracoclavicular ligaments

Answer 4

2 parts, major stabilizing ligament

Question 5

outline the coracoacromial ligament

Answer 5

forms arch (for head of the humerus)
prevents superior dislocation

Question 6

Outline the glenohumeral joint and its actions

Answer 6

ball n socket joint, between large head of the humerus and glenoid fossa.

abduction/ adduction, flexion/ extension, circumduction and lateral/medial rotation

Question 7

Outline abduction in the shoulder region

Answer 7

Performed by deltoid

origin: spine of scapula, acromion and clavicle
insertion: deltoid tuberosity

Question 8

outline adduction in the shoulder region

Answer 8

performed by latisimus dorsi and pectoralis major.

Question 9

abduction/ adduction of the arm

Answer 9

glenohumeral joint accommodates and rotation of the scapula increase the range of movement.

Question 10

Why is the glenohumeral joint so unstable

Answer 10

The humeral head is very large and the glenoid fossa is very shallow

Question 11

What factors increase joint stability in the shoulder

Answer 11

1) Corachoacromial arch prevents superior dislocation
2) glenohumeral ligaments support an anterior aspect of joint
3) glenoid labrum, skirt surrounding glenoid foss- fibrocartilage ring.
4) long head of biceps n triceps, splint the joint above and below
5) tendons of the rotator cuff muscles

Question 12

Name the rotator cuff muscles

Answer 12

Teres minor, infraspinatus, superspinatus, subscapularis

Question 13

Where does subscapularis originate and insert, where is it found

Answer 13

sits in subscapular fossa,

origin: ant surface of the scapula
insert: lesser tubercle

Question 14

Where does supra/infraspinatus and teres minor insert into

Answer 14

They insert into the greater tubercle

Question 15

What are the functions of the rotator cuff muscles

Answer 15

supraspinatus- initiate abduction
infraspinatus- lateral rotation
teres minor- lateral rotation

Question 16

Outline the function of teres major

Answer 16

Performs radial rotation
stabilizes humerus during abduction but doesn’t cuff so it isn’t classified as an rcm
inserts into the medial lip of the bicipital groove

Question 17

What is the most common rotator cuff injury

Answer 17

supraspinatus impingement, most commonly injured

as there is limited space for tendon below the coracoacromial arch

Question 18

Outline the nerve supply to the shoulder region

Answer 18

the superior trunk has the subscapular nerve coming off to supply the supra/ infraspinatus

posterior cord supplies the shoulder region,
upper and lower nerves supply the subscapularis, trees major
thoracodorsal nerve supplies lattisimus dorsi

Question 19

What are the borders of the quadrangular space

Answer 19

teres minor (sup border), major (inf border)
the humerus ( lateral border) and long head of the tricep (medial border)