Injections/nerve blocks

Question 1

Eq injection: Coffinjoint­

Answer 1

1. Dorsal: 1-2cm prox. to coronary band. Needle penetrates EDC tendon. Insert from a vertical position and directed distally.
2. Palmar: into the navicular bursa
   - Synovia may escape, or you can aspirate it. If so, you are in the right place.
   - Blocks entire coffin joint, and navicular bursa by diffusion

Question 2

Eq injection: Fetlockjoint­

Answer 2

Twooptions:
1.Palmar/plantarrecesses:(better) recessis located prox. topSB and dist. to the lat. splintbone, bw. cannon bone and suspensorylig. (itisbetteriftheanimalstandsfully→increasesthewidthofthejointcapsule).
­2.Dorsal recess:theneedle is insertedinobliquemanner undertheEDC tendon.

Question 3

Eq injection: Pastern joint

Answer 3

• Dorsal: 1-2 cm prox. to joint. Needle is inserted lat. to CDE, 1.5cm below lat. eminence of dist. aspect of Ph1.
• Palmar: Needle is inserted prox. to transverse prominence on the palmar aspect of Ph2, under DDF tendon.

Question 4

Eq injection: Carpus

Answer 4

• Radiocarpal joint: injected dorsally, with the carpus flexed. Palpated as an indentation on medial or lateral side of ECR tendon. Needle directed straight into indentation, about 2cm dist. to the V created by ECU and EDL.
• Intercarpal joint: Capsule found about 3cm dist. to radiocarpal joint on the palmar lat. surface. Carpus flexed and indentation medial or lateral side of ECR tendon. The needle is directed straight into the indentation.
• Lateral approach: palpate notch created by the ECU tendon and LDE tendon. Insert the needle into small depressions immediately distal to this notch. Can be performed with horse standing on limb.

Question 5

Eq injection: Elbow joint

Answer 5

1. Needle is inserted cran. to the lat.collat.lig.

2. Needle is inserted bw. lat.epicondyle and olecranon.

Question 6

Eq injection: Shoulder joint

Answer 6

1. Needle is inserted in a caudodors. direction bw. the cran and cau portion of greater tubercle (cran. to tendon of infraspinatus)
2. Needle is inserted in a craniodors. direction, 8cm dist. and 9cm cau. to the cran. portion of greater tubercle.

Question 7

Eq injection: Low 4 point Nerve Block

Answer 7

1. R.pulvinus: Bulb at heel. Prox. margin of hoof cartilage.
2. R.palmaris: halfway bw the coronary band and fetlock joint (Ø blocking of R.dors)
3. N.palmaris: inject at the dist. end of pSB
4. N.digitalis palmaris: bw DDF tendon and susp.lig., halfway up length of MC3
   - Blocks DDF/SDF tendon up to level of block; insertion/branches of suspensory ligament

Question 8

Eq injection: 6 point Nerve Block

Answer 8

Lateral and medial plantar nerves, and lateral and medial metatarsal nerves: these are blocked identical to the 4-point block in FL.
-Dorsal Metatarsal nerves innervate dorsal surface,
therefore an additional subcutaneous ring block is directed dorsally.
-Blocks fetlock joint and all structures below; DDF/SDF tendon up to level of block; insertion/branches of susp.lig.

Question 9

Eq injection: Proximal MC/MT

Answer 9

-High 4 point block: block palmar nerves bw DDF tendon and susp.lig., and block palmar MC nerves axial to splint
bone and abaxial to susp.lig.
-Local infiltration of susp.lig: directly infiltrate along axial aspect of splint bones, directly next to susp.lig.
-Lateral palmar: anaesthetise the lateral palmar nerve as it courses along the medial aspect of acc. carpal bone.
-Blocks all structures distal to the carpus, including the prox. susp.lig.

Question 10

Eq injection: Median Nerve Block

Answer 10

5cm distal to elbow joint, on the medial aspect of the

limb. The needle is walked off the caudal aspect of the radius.

Question 11

Eq injection: Ulnar Nerve Block

Answer 11

10cm proximal to acc. carpal bone, bw FCU and ECU

Question 12

Eq injection: Fibular Nerve Block

Answer 12

• Deep and Superficial Fibular Nerve
• Lateral aspect of limb
• 10cm prox. to the point of the hock, in a groove created by the Long and Lateral Digital Extensor muscles.
• Blocks entire limb from distal tibia down, including tarsus

Question 13

Eq injection: Tibial Nerve Block

Answer 13

• 10cm proximal to Calcaneous, bw DDF and SDF tendon
• (nerve lies closer to medial aspect of the limb)
• Blocks entire limb from distal tibia down, including tarsus

Question 14

Eq injection: Tarsus

Answer 14

1. Tibio-Tarsal/Tarso-Crural join: Approached on the dorso-medial aspect of the hock, where the joint pouch is easily palpated. The needle is inserted directly inwards. Can inject the medial or lateral plantar pouch of Tibio-Tarsal joint.
2. Distal Intertarsal joint: medial aspect. Needle inserted into small, T-shaped gap formed by the junction of T3 and TC. The gap is immediately distal to the Cunean tendon.
3. Tarsal-metatarsal joint: plantar-lateral aspect. Needle is inserted immediately above the head of the lateral splint bone. Needle is angled in a dorsal-medial and distal direction.

Question 15

Eq injection: Stifle Joint Block

Answer 15

1. Medial Femoral-Tibial: needle inserted bw med.patellar lig. and med.collateral lig., prox. to the tibial tuberosity.
2. Femoral-Patellar:
   - Cran. approach: needle inserted bw medial and intermediate patellar lig, 4cm prox to the tibial tuberosity. Needle angled upwards, towards supra-patellar recess.
   - Lat.approach: needle is inserted 6cm above the lat. tibial condyle, behind the caudal edge of lat.patellar lig.
3. Lateral Femoral-Tibial: (into extensor recess) Needle is inserted caudal to lat.collat.lig, just prox. to tibia. Bw. lat.patellar.lig. and EDL.

Question 16

Ca: Radial Nerve Block

Answer 16

Push lateral head of triceps back, and inject proximal to epicondyle (for operation on dorsal antebrachium)

Question 17

Ca: Median Nerve Block

Answer 17

Over-extend the carpus, and feel for the median nerve bw M. flexor carpi radialis and SDF. Will feel nerve with thumb (on medial aspect of leg)

Question 18

Ca: Tibial Nerve Block

Answer 18

-Find tibial nerve in soft tissue between common calcanean tendon and digital flexors; pinch
skin with two fingers and pull to feel the nerve jumping
-Inject from medial aspect
-Aspirate to make sure you are not in the caudal branch of the saphenous artery (which accompanies the tibial nerve in this groove).
-The skin fold is very thin.

Question 19

Ca: Common Peroneal/Fibular Nerve

Answer 19

N. peroneus/fibularis communis block: it is very hard to give a distinct nerve block to the dog.
-Locate peroneal nerve by head of fibula (lateral aspect)
-Inject a little bit proximally to it
or
-Palpate the groove bw the EDL and peroneus longus, half way bw the stifle and the hock (proximal to branching of the lateral saphenous vein)

Question 20

Epidural

Answer 20

-Epidural space: Under the Lig. Flavum, near the Dura Mater
-Spatium Subdurale: appears on penetrating Dura Mater and letting some air in (artificial space). May also appear when there is bleeding.
-Spatium Subarachnoidale: presence of cerebro-spinal fluid
-As you penetrate with a needle, you will feel 2 resistances: Lig.Flavum and Dura Mater. The rest of the tissues lack resistance.
o Two resistances to collect cerebro-spinal fluid; one resistance for the epidural injection (go in two resistances, then withdraw one)
1. Epidural space
2. Subdural space
3. Subarachnoid space
-Dog: Lumbosacral space: L7-S1
-Cat: Cau1-Cau2/Cau2-Cau3 (in the tail)
-Cow/Horses: Sa5-Cau1. In the cow, tail vertebrae may be broken. In that case, move to Ca1-Ca2

Question 21

Eq: Podotrochlear (navicular) bursa

Answer 21

Middle between bulbs of the heels and base of
digital fossa (from caudal aspect of the foot).