2- Equine Musculoskeletal 1

Question 1

Label the diagram

Answer 1

1) Deep pectoral
2) Superficial pectoral
3) Sternum

Question 2

Label the diagram

Answer 2

1) Rhomboideus
2) Serratus ventralis
3) Serratus ventralis

Question 3

Label the diagram (lateral view)

Answer 3

1) Supraspinatus
2) Infraspinatus

Question 4

What is the OIA of supraspinatus m.?

Answer 4

O: Supraspinous fossa
I: Greater and lesser tubercles of humerus
A: Extend and laterally stabilize the humeral joint

Question 5

What is the OIA of infraspinatus

Answer 5

O: Infraspinatus fossa
I: Superficial tendon- on the greater tubercle of the humerus
I: Deep tendon- on the caudal eminence of greater tubercle
A: Laterally stabilize the humeral joint

Question 6

Label the diagram

Answer 6

1) Subclavius (not in dogs or cats!!)
2) Deltoideus

Question 7

What is the OIA of deltoideus

Answer 7

O: Caudal border of scapula
I: Deltoid tuberosity
A: Flex the humeral joint
**Equine scapula does not have acromion, don’t have acromial part like in dog

Question 8

What is the OIA for Subclavius m.

Answer 8

O: Cranial part of the sternum closely associated to supraspinatus m.
I: Supraspinatus muscle epimysium
A: Covers the jugular vein cranially
**Not in dogs or cats

Question 9

Label the diagram

Answer 9

1) Subscapularis
2) Teres major

Question 10

What is the OIA for subscapularis?

Answer 10

O: Subscapular fossa
I: Lesser tubercle of the humerus
A: Medially stabilize the humeral joint

Question 11

What is the OIA of Teres Major?

Answer 11

O: Caudal angle of the scapula and adjacent border of scapula
I: teres major tuberosity of humerus
A: Flex humeral joint

Question 12

Label the diagram

Answer 12

1) Intertubercular bursa
2) Biceps Brachii
3) Lacertus fibrosus

Question 13

What is the OIA of biceps brachii

Answer 13

O: Supraglenoid tubercle
I: Intertubercular bursa
A: Flex the cubital joint, extend the humeral joint

Question 14

What is the Intertubercular bursa?

Answer 14

Located between the tendon of origin of biceps brachii and the Intertubercular grooves of the humerus

Question 15

What is the lacertus fibrosis

Answer 15

• Tendinous insertion of biceps brachii on the extensor carpi radial is m.
• part of the stay apparatus
• like a rubber band to flex the cubital joint
  ***Very hard upon palpation, feels almost like a bony prominence

Question 16

Label the diagram

Answer 16

1) Biceps brachii
2) Extensor carpi radialis
3) Lacertus fibrosus

Question 17

Label the diagram of heads of triceps brachii

Answer 17

1) long head
2) Medial head
3) Long head
4) Lateral head
**no accessory head in horses

Question 18

What is the OIA for triceps brachii?

Answer 18

O- Long head: caudal border of the scapula
O- Lateral head: deltoid tuberosity
O- Medial head: medial aspect of humerus
I: olecranon tuber
A: extend the cubital joint and flex the humeral (long head)

Question 19

Label the diagram

Answer 19

1) Extensor Carpi Radialis
2) Common digital extensor

Question 20

What is the OIA of extensor carpi radialis?

Answer 20

O: Lateral supracondylar crest of the humerus
I: Metacarpal tuberosity
A: Extend and fix the carpus and flex the elbow joint

Question 21

Which nerve innervates the extensor carpi radialis?

Answer 21

Radial n.

Question 22

What is the OIA of the common digital extensor?

Answer 22

O: Lateral epicondyle of the humerus
I: Extensor process of distal phalanx and dorsal surface of proximal and middle phalanges
A: Extend the carpus and digit and flex the elbow joint

Question 23

Which nerve innervates the common digital extensor?

Answer 23

Radial n.

Question 24

Label the diagram

Answer 24

1) Lateral Digital Extensor
2) Extensor carpi ulnaris (Ulnaris Lateralis)

Question 25

What is the OIA for lateral digital extensor?

Answer 25

O: Lateral tuberosity of the radius, lateral collateral ligament of the elbow
I: Dorsal aspect of proximal phalanx
A: Extend the carpus and digit

Question 26

What nerve innervates the lateral digital extensor?

Answer 26

Radial n.

Question 27

What is the OIA of extensor carpi ulnaris (ulnaris lateralis)? This is a weird one

Answer 27

O: Lateral epicondyle of the humerus
I: Short tendon- accessory carpal bone
I: Long tendon- metacarpal bone IV
A: FLEX and abduct the carpus
Notice it is opposite from the name

Question 28

What nerve innervates the extensor carpi ulnaris?

Answer 28

Radial n.

Question 29

Label the diagram

Answer 29

1) Flexor carpi ulnaris
2) Flexor carpi radialis

Question 30

What is the OIA of flexor carpi ulnaris?

Answer 30

O- Humeral head: medial epicondyle of the humerus
O- Ulnar head: Olecranon
I: Accessory carpal bone
A: Flex the carpus and extend the elbow joint

Question 31

What nerve innervates flexor carpi ulnaris?

Answer 31

Ulnar n.

Question 32

What is the OIA of flexor carpi radialis?

Answer 32

O: Medial epicondyle of the humerus
I: Metacarpal bone II
A: Flex the carpus and extend the elbow joint

Question 33

Which nerve innervates the flexor carpi radialis?

Answer 33

Median n.

Question 34

Red? Green?

Answer 34

Green: Superficial digital flexor
Red: Deep digital flexor

Question 35

What is the OIA of SDF?

Answer 35

O: Medial epicondyle of the humerus and radius (proximal accessory ligament)
I: Flexor surfaces of proximal and middle phalanges
A: Flex the digit (proximal interphalangeal joint) and carpus and extend the elbow joint

Question 36

What nerve innervates the SDF?

Answer 36

Ulnar n.

Question 37

What is the OIA of DDF?

Answer 37

O- Humeral head: medial epicondyle of the humerus (distal accessory ligament)
O- Ulnar head: Olecranon
O- Radial head: radius
I: Flexor surface of the distal phalanx
A: Flex the digit and carpus and extend the elbow joint

Question 38

What nerve or nerves innervates the DDF?

Answer 38

Median and ulnar nn.

Question 39

Name the 4 anatomical areas of the suspensory ligament

Answer 39

Blue- proximal
Purple- mid body
Yellow- branches
Green- extensor branches
Orange- distal sesamoidean ligaments

Question 40

What is another name for the suspensory ligament?

Answer 40

Interosseous muscle