Ch 65 - Amputations

Question 1

What local anaesthetics can be used for blocking nerves during amputation?
What is the maximum dose?

Answer 1

• 0.5% bupivicaine or 0.5% ropivicaine
• Maximum 2mg/kg

Question 2

What are the options for thoracic limb amputation?

Answer 2

• Removal of the scapula
• Disarticulation

Question 3

What vessels and nerves are encountered during amputation by removal of the scapula?

Answer 3

• Omobrachial and cephalic vein
• Branches of superficial cervical artery including suprascapular artery
• Lateral thoracic artery, vein and nerve
• Thoracodorsal artery, vein and nerve
• Brachial plexus
• Axillary artery and vein
• External thoracic artery

Question 4

Where can the superficial cervical and axillary LNs be located during forelimb amuptation?

Answer 4

• Superficial cervical LN: Located along prescapular branch of superficial cervical artery at its cranial aspect, deep to brachiocephalicus muscle
• Axillary LN: Located along lateral thoracic artery, caudal to axillary vein, medial to latissimus dorsi and deep pectoral muscles

Question 5

List the options for pelvic limb amputation

Answer 5

• Disarticulation
• Osteotomy of the femur (mid-femoral)
• En bloc with acetabulectomy

Question 6

Why does osteosarcoma more commonly cross the hip joint?

Answer 6

Ligament of the head of the femur is though to act as a bridge

Question 7

What blood vessels and nerves are encountered during a pelvic limb amputation via disarticulation?

Answer 7

• Femoral artery and vein
• Saphenous nerve (cranial/lateral to femoral artery)
• Medial circumflex femoral artery (caudally in femoral triangle)
• Superficial circumflex iliac artery and lateral circumflex femoral artery and vein may need to be ligated if femoral artery and vein are ligated distal to these branches
• Caudal gluteal artery and vein
• Sciatic nerve
• Femoral nerve

Question 8

What osteotomies are required for an acetabulectomy?

Answer 8

Ilial body, ischium and pubis

Question 9

What alteration is recommended if performing a THR in a dog with a contralateral pelvic limb amputation?

Answer 9

Recommended to place the acetabular cup in a more closed position to decreases the risk of luxation (4/9 amputees had post-THR luxation in one study)

Question 10

List the options for prostheses after a partial limb amputation

Answer 10

• Intraosseous (intraosseous transcutaneous amputation prosthesis ITAP)
• Socket prosthesis

Question 11

How much of the limb must be remaining for a socket prosthesis?

Answer 11

At least 30% of the radius/ulna or tib/fib

Question 12

What is a partial foot amputation?

Answer 12

Amputation of two adjacent digits en bloc, with or without the corresponding MC/MT bones

Question 13

How does the vasculature of the tail differ in the cranial tail compared to the tip of the tail?

Answer 13

• Cranial 1/3 of the tail, there are typically 7 longitudinal arterial trunks
• Only the 2 lateral caudal arteries and the median caudal artery reach the tip