Intrinsic Muscles Of The Brachium

Question 1

Supraspinatus

Answer 1

Origin: supraspinous fossa
Insertion: greater tubercle of humerus
Action: extension and stabilisation

Question 2

Deltoideus

Answer 2

Origin: scapula spine + acromion
Insertion: deltoid tuberosity
Action: flex shoulder

Question 3

Infraspinatus

Answer 3

Origin: infraspinous fossa
Insertion: greater tubercle of humerus
Action: flex,el extend, abduct, rotate, stabilise depending on angle shoulder is at

Question 4

There’s minor

Answer 4

Origin: infraglenoid tubercle and caudal border of scapula
Insertion: teres minor tuberosity on greater tubercle
Action: flex, lateral rotation, prevent medial rotation

Question 5

Subscapularis

Answer 5

Origin: subscapular fossa
Insertion: lesser tubercle of humerus
Action: adduct, extend and stabilise when non weight bearing. Medial rotation when weight bearing

Question 6

Teres major

Answer 6

Origin: caudal border of scapula and subscapularis
Insertion: teres major tuberosity (medial side of humerus)
Action: flex and medially rotate shoulder

Question 7

Coracobrachialus

Answer 7

Origin: coracoid process of scapula
Insertion: lesser tubercle of humerus
Action: adduct, extend and stabilise shoulder

Question 8

Tensor fascia antebrachii

Answer 8

Origin: fascia on lateral side of latissimus dorsi
Insertion: olecranon
Action: extend elbow

Question 9

Triceps brachii - long head

Answer 9

Origin: caudal border of scapula
Insertion: olecranon tuber
Action: extend elbow and flex shoulder

Question 10

Triceps brachii - lateral head

Answer 10

Origin: tricipital line of humerus
Insertion: olecranon tuber
Action: extend elbow

Question 11

Triceps brachii - accessory head

Answer 11

Origin: neck of humerus
Olecranon tuber
Action: extend elbow

Question 12

Triceps brachii - medial head

Answer 12

Origin: lesser tubercle
Olecranon tuber
Action: extend elbow

Question 13

Anconeus

Answer 13

Origin: lateral supracondylar crest and lateral + medial epicondyles
Insertion: olecranon
Action: extend elbow

Question 14

Biceps brachii

Answer 14

Origin: supraglenoid tubercle
Insertion: ulna and radius tuberosities
Action: flex elbow and extend shoulder

Question 15

Brachialus

Answer 15

Origin: proximal lateral humerus
Insertion: ulnar and radial tuberosities
Action: flex elbow