THRA.24

Question 1

The architecture of the trunk is referred to as…

Answer 1

‘Bow and string’ theory

Bow: thoracolumbar vertebrae

String: abdominal muscles

Question 2

Design of the body is to allow…

Answer 2

Low energy expenditure

Question 3

The joints of the animal should be stabilised to…

Answer 3

• Prevent unwanted abduction/adduction
• Coordinate flexion/extension

Maximising efficient transmission of thrust

Question 4

M. serratus ventralis is adapted to…

Answer 4

• Carry considerable weight with minimum effort
• Due to high tendinous tissue

Question 5

The function of collateral ligaments

Answer 5

• Limit range of flexion and extension
• Exception: Shoulder joint

Question 6

The function of collateral ligaments in the shoulder

Answer 6

• Present a force which must be overcome to move
• Prevents flexion of the elbow due to body weight

Question 7

Stay apparatus

Answer 7

• Tendinous-ligamentous support system in equine
• Allows the horse to stand for long periods

Question 8

Give the mechanism of the stay apparatus

Answer 8

Whilst standing

• Contraction of the supraspinate and triceps muscles
• Tension of superficial + deep digital flexor muscles

Results in passive tension → Maintains elbow extension

Question 9

Why is weight-bearing on the carpus effortless?

Answer 9

Axis of the radius + cannon bone are in the same vertical line

Question 10

The carpus is prevented from buckling forward by the…

Answer 10

Lacertus fibrosus

Question 11

Overextension of the carpus is prevented by…

Answer 11

• Caudal ligaments
• Ligaments of the accessory bone
• Check ligaments

Question 12

What provides the main support of the fetlock?

Answer 12

Suspensory ligament

(Palmar + planter)

Question 13

Suspensory ligament prevents…

Answer 13

Overextension of the fetlock during locomotion

Question 14

During locomotion, the suspensory ligament is supported by…

Answer 14

SDF + DDF

Question 15

Answer 15

Suspensory ligament

Question 16

Answer 16

Lacertus fibrosus

Question 17

Effect of body weight on the fetlock joint

Answer 17

Extends the fetlock

Question 18

Which structures prevent muscular effort in the equine hindlimb?

Answer 18

• Collagenous bands derived from muscular tissue
• Skeletal adaptations

Question 19

What does this figure represent?

Answer 19

The patellar lock/loop

Question 20

Answer 20

Middle patella ligament

Question 21

Answer 21

Superficial digital flexor tendon

Question 22

Answer 22

Third fibular muscle

Question 23

Answer 23

Accessory ligament

Question 24

Answer 24

Suspensory ligament

Question 25

Patellar loop causes

Answer 25

* Locking of patella * Immobilisation of the stifle * Immobilisation of the hock

Question 26

Initiation of the patella loop

Answer 26

* Extension of stifle beyond the proximal trochlear groove * Medial twist of the patella * Parapatellar cartilage is hooked over the trochlear tubercle

Question 27

Function of patella loop

Answer 27

* Allows the horse to rest its weight on one hindlimb * With minimum effort

Question 28

How is the patella loop stopped?

Answer 28

* Weight is shifted to the other limb * Quadriceps draws the patella proximally

Question 29

If the patella loop cannot be unlocked, what can be observed?

Answer 29

The horse drags the toe

Question 30

Reciprocal apparatus

Answer 30

* Flexion of the stifle * Flexion of the hock

Question 31

Muscles involved in the reciprocal apparatus

Answer 31

* Gastrocnemius * Third peroneal muscle * SDF

Question 32

Give the _natural gaits_

Answer 32

* Equine: * Walk * Trot * Gallop * Other animals: * Pace * Amble * Rack

Question 33

Walk

Answer 33

* 4-beat gait * 2 feet always in contact with the floor 1. Left hind 2. Left fore 3. Right hind 4. Right fore

Question 34

Trot

Answer 34

* 2-beat gait * Opposite fore + hind feet hit the ground together 1. Right fore + left hind 2. Left fore + right hind

Question 35

Gallop

Answer 35

* 4-beat gait * Either left or right forelimb leads 1. Right fore 2. Left hind 3. Right hind 4. Left fore

Question 36

Answer 36

Walking

Question 37

Answer 37

Trotting

Question 38

Answer 38

Gallop

Question 39

What is a stride sequence?

Answer 39

Movement of a limb with: * Swing phase * Stance phase