6- Equine Limb Vessels and Nerves

Question 1

Which muscles does the suprascapular nerve innervate?

Answer 1

Motor to supraspinatus and infraspinatus mm.

Question 2

Which muscle(s) does the subscapular nerve innervates? Is it motor or sensory?

Answer 2

Motor to subscapularis m.

Question 3

Which structures does the axillary nerve supply motor innervation to?

Answer 3

Teres major m.
Teres minor m.
Deltoideus m.
Caudal part of subscapularis m.

Question 4

Which structures does the axillary nerve supply sensory innervation to?

Answer 4

Craniolateral shoulder area
Cranial aspect of the antebrachium

Question 5

Which structures does the musculocutaneous nerve supply motor innervation to?

Answer 5

Biceps brachii m.
Brachialis m.

Question 6

Which structures does the musculocutaneous nerve supply sensory innervation to?

Answer 6

Medial antebrachium region

Question 7

Which structures does the median nerve supply motor innervation to?

Answer 7

Flexor carpi radialis
SDF
DDF

Question 8

Which structures does the median nerve supply sensory innervation to?

Answer 8

Palmar aspect of the manus

Question 9

Which structures does the radial nerve supply motor innervation to?

Answer 9

Proximal limb:
Triceps brachii m.
tensor fasciae antebrachii m.
Anconeus m.

Distal limb:
Whole extensor group plus supinator

Question 10

The radial nerve divides into the superficial branch and deep branch after it innervates the triceps. State which branch is motor, which branch is superficial, and what each branch innervates.

Answer 10

Deep branch- motor
- innervates extensors and supinators of the antebrachium

Superficial branch- sensory
- Cranial and lateral aspect of antebrachium
- medial and dorsal aspect of the manus

Question 11

Which structures does the femoral nerve supply motor innervation to?

Answer 11

Gluteal muscles, quadriceps femoris, and sartorius (motor from saphenous which is a branch off of femoral)

Question 12

Which structures does the saphenous nerve supply sensory innervation to?

Answer 12

Remember femoral nerve gives rise to saphenous nerve

Cutaneous innervation to skin of medial femoral region, medial crus, medial pes

Question 13

Which structures does the obturator nerve supply motor innervation to?

Answer 13

Adductors of pelvic limb
- external obturator
- pectineus
- Gracilis
- adductor

Question 14

Which structures does the sciatic nerve supply motor innervation to?

Answer 14

Internal obturator, gemelli, quadratus femoris within pelvis
Biceps femoris, semimembranosus, and semitendinosus caudal to the hip

Question 15

Which structures does the sciatic nerve supply sensory innervation to?

Answer 15

Lateral and caudal surfaces of crus

Question 16

Describe the technique for the Palmar Digital Nerve Block.

Answer 16

Insert the needle over the neurovascular bundle at the proximal border of the collateral cartilage

Question 17

Which nerves are affected by the Palmar Digital Nerve Block, and which structures will loose feeling?

Answer 17

Palmar Digital nerves
- sole
- navicular apparatus
- coffin joint
- distal flexor tendon sheath
- distal sesamoidean ligaments
- loss of skin sensation at the heel

Question 18

Describe the technique for the abaxial sesamoid nerve block

Answer 18

Insert the needle at the abaxial surface of the sesamoid, point needle distally

Question 19

Which nerves and structures are anesthetized when the abaxial sesamoid nerve block is performed?

Answer 19

Palmar digital nerves
- Foot
- middle phalanx
- pastern joint
- distal proximal phalanx
- distal SDF and DDF
- distal sesamoidean ligaments
- distal annular ligament
- +/- fetlock joint

Question 20

Describe the technique used to perform the low 4-point block

Answer 20

• Insert the needle distal to the button of the splint medially and laterally
• insert the needle SQ between the suspensory ligament and the DDF tendon

Question 21

What nerves are affected when the low 4-point block is performed?

Answer 21

• Palmar metacarpal/ metatarsal nerves (adjacent to splint bones)
• Palmar nerves (between suspensory and SDF tendon

Question 22

What structures are affected when the low 4-point block is performed?

Answer 22

• All structures affected by lower two blocks
• fetlock joint
• suspensory branches
• more proximal SDF/DDF tendons

Question 23

Describe the technique used to perform a high 4 point block on the front limb

Answer 23

• inject SQ on dorsal surface of the DDFT through the fascia just distal to the carpometacarpal joint
• flex the limb and insert the needle along the splint bones pointed at palmar metacarpal 3

Question 24

What nerves are affected when the high 4-point block is performed on the front limb?

Answer 24

• medial and lateral palmar nerves
• medial and lateral palmar metacarpal nerves

Question 25

What structures are affected when the high 4-point block is performed on the front limb?

Answer 25

- flexor tendons - splint bones - interosseous ligaments - proximal suspensory ligament - inferior check ligament

Question 26

Describe the technique used for the high 4 (6) point block on the pelvic limb

Answer 26

- 1.5in needle inserted distal to the TMT on wither side of and hit the back of metacarpal 3 - deposit 3-5 mL through eh fascia over the DDF on medial and lateral side - 2cm distal to the TMT at 10 and 2 o’clock positions on the dorsal cannon bone

Question 27

What nerves and structures are affected when the high 4 (6) point block is performed on the hind limb?

Answer 27

- medial and lateral plantar nerves - medial and lateral plantar metatarsal nerves Everything distal to the tarsometatarsal (TMT) except the dorsal over the cannon bone

Question 28

What is sweeny shoulder in horses?

Answer 28

Damage to the suprascapular nerve results in atrophy of supra and infraspinatus, shoulder instability, and shoulder "slip". The spine of the scapula will be very easy to see once those muscles atrophy.

Question 30

What is 1 & 2?

Answer 30

Ulnar nerve Median nerve

Question 31

What is 3 & 4?

Answer 31

Palmar branch of ulnar nerve Dorsal branch of ulnar nerve

Question 32

What is 5 & 6?

Answer 32

Lateral palmar nerve Deep branch of lateral palmar nerve

Question 33

What is 6, 7, & 8?

Answer 33

Deep branch of lateral palmar nerve Communicating branch Palmar metacarpal nerves

Question 34

What is 9, 10, & 11?

Answer 34

Dorsal branch of digital nerve Lateral palmar digital nerve Medial palmar digital nerve

Question 35

Label autonomous zones on horse thoracic limbs

Answer 35

1) Ulnar 2) Radial 3) Ulnar 4) Ulnar 5) Musculocutaneous 6) Ulnar

Question 36

Label autonomous zones on bovine thoracic limbs

Answer 36

1) Ulnar 2) Musculocutaneous 3) Median 4) Ulnar 5) Radial 6)Ulnar

Question 37

Label diagram of nerves on the palmar aspect of horse fore limb

Answer 37

Yellow- median and medial palmar Blue- Ulnar, turns into palmar branches Pink- Medial metacarpal Red- Lateral metacarpal Green- lateral palmar

Question 38

Label the nerves on the dorsal aspect of the thoracic limb

Answer 38

Purple- Medial cutaneous antebrachial nerve Blue- Ulnar nerve and dorsal branch Yellow- Medial palmar Green- Lateral palmar

Question 39

Label the autonomous zones on horse hind limbs

Answer 39

1) Saphenous 2) Tibial 3) Peroneal 4) Tibial

Question 40

Label the autonomous zones of bovine hind limbs

Answer 40

1) Saphenous 2) Sciatic 3) Peroneal 4) Tibial 5) Sciatic 6) Saphenous 7) Peroneal 8) Tibial

Question 41

Label the nerves on the plantar view of the horse hind limb

Answer 41

Yellow- Medial plantar Green- Lateral plantar Light green- tibial Pink- medial plantar metatarsal Red- Lateral Plantar Metatarsal

Question 42

Label the diagram of the nerves on the dorsal view of horse pelvic limb

Answer 42

Doodoo brown- Saphenous Blue- Deep Fibular Teal- Caudal cutaneous sural Red- Superficial fibular Light purple- Medial dorsal metatarsal Purple- Lateral dorsal metatarsal Green- lateral plantar Yellow- medial plantar

Question 43

If you suspect an injury to the suspensory branches of the interosseus, which nerve block should you perform?

Answer 43

Low 4-point block

Question 44

if you suspect an access in the sole of a horses hoof, which nerve block should you perform?

Answer 44

palmar digital block

Question 45

If you suspect a horse is painful in its pastern joint, which nerve block should you perform?

Answer 45

Abaxial sesamoid block

Question 46

If you suspect an injury to the fetlock joint, which nerve block should you perform?

Answer 46

Low 4-point block

Question 47

If you suspect a horse has sustained an injury to a splint bone, which nerve block should you perform?

Answer 47

High 4-point block