NAVLE Equine Surgery and Lameness 2 — Questions and Answers
Question 1: A 7-year-old Warmblood gelding presents with acute onset right forelimb lameness and a positive flexion test of the distal limb. Nerve blocks reveal pain originating from the palmar digital nerves. Radiographs show pedal osteitis. Which treatment is most appropriate for long-term management?
- Palmar digital neurectomy (Correct answer)
- Coffin joint corticosteroid injection
- Deep digital flexor tenotomy
- Navicular bursa lavage
Correct answer: Palmar digital neurectomy
Palmar digital neurectomy is indicated for horses with chronic foot pain (including pedal osteitis) that have failed conservative management, providing long-term desensitization of the heel and sole.
Question 2: During colic surgery, you identify a large colon displacement in which the left dorsal colon is displaced laterally under the spleen and nephrosplenic ligament. What is this condition called and what is the initial non-surgical treatment?
- Right dorsal displacement; phenylephrine and rolling
- Left dorsal displacement (nephrosplenic entrapment); phenylephrine and rolling (Correct answer)
- Cecal volvulus; nasogastric decompression
- Right dorsal displacement; heparin therapy
Correct answer: Left dorsal displacement (nephrosplenic entrapment); phenylephrine and rolling
Nephrosplenic (left dorsal) displacement involves the colon entrapped over the nephrosplenic ligament and can often be corrected non-surgically using phenylephrine to contract the spleen combined with controlled rolling under general anesthesia.
Question 3: A 3-year-old Thoroughbred filly has a 2-week history of progressive right hindlimb lameness. Palpation reveals pain at the proximal suspensory ligament. Ultrasound shows a core lesion at the origin. Which diagnostic technique best confirms proximal suspensory desmitis in the hindlimb?
- Periarticular analgesia of the tarsometatarsal joint
- High 4-point nerve block
- Deep peroneal nerve block (Correct answer)
- Perineural analgesia of the tibial nerve only
Correct answer: Deep peroneal nerve block
A deep peroneal (fibular) nerve block desensitizes the proximal suspensory ligament origin in the hindlimb, helping confirm proximal suspensory desmitis as the source of pain.
Question 4: A horse undergoes exploratory laparotomy for small intestinal volvulus. After 3 hours of surgery, the horse develops tachycardia, hypotension, and pale mucous membranes. Lactate is 12 mmol/L. What does this lactate value primarily indicate?
- Excessive intraoperative fluids causing hemodilution
- Severe tissue hypoperfusion and anaerobic metabolism (Correct answer)
- Hepatic failure from anesthetic agents
- Normal response to surgical stress
Correct answer: Severe tissue hypoperfusion and anaerobic metabolism
A lactate of 12 mmol/L indicates severe systemic hypoperfusion with anaerobic metabolism, which is a poor prognostic indicator in equine colic surgery.
Question 5: A 10-year-old Quarter Horse mare has medial meniscal damage confirmed on MRI. What is the most accurate statement regarding equine stifle meniscal injuries?
- Medial meniscal tears heal reliably with intra-articular steroids alone
- Arthroscopic debridement is the preferred surgical treatment for partial tears (Correct answer)
- Lateral meniscal tears are more common than medial tears in horses
- Meniscal injuries rarely cause stifle effusion
Correct answer: Arthroscopic debridement is the preferred surgical treatment for partial tears
Arthroscopic debridement of damaged meniscal tissue is the preferred surgical approach for partial meniscal tears in horses, providing access to the caudal pouch of the femorotibial joint.
Question 6: A Quarter Horse presents with acute, severe forelimb lameness and a draining tract near the coronary band. Radiographs show gas lucency within the third phalanx. What condition do these findings most strongly suggest?
- Subsolar abscess with secondary osteomyelitis of the distal phalanx (Correct answer)
- Navicular bone fracture
- Coffin joint septic arthritis
- Sequestrum formation of the proximal phalanx
Correct answer: Subsolar abscess with secondary osteomyelitis of the distal phalanx
A draining tract at the coronary band combined with gas and lytic changes in the third phalanx are classic findings of a chronic subsolar abscess that has ascended and caused osteomyelitis of the distal phalanx.
Question 7: Which anesthetic protocol is most commonly associated with post-anesthetic myopathy in horses undergoing prolonged recumbency?
- Total intravenous anesthesia with ketamine-xylazine-guaifenesin
- Inhalant anesthesia with hypotension and poor padding (Correct answer)
- Epidural analgesia with detomidine
- Regional nerve blocks prior to induction
Correct answer: Inhalant anesthesia with hypotension and poor padding
Post-anesthetic myopathy in horses is most strongly associated with inhalant anesthesia combined with hypotension and inadequate padding, leading to compartment syndrome of dependent muscles.
NAVLE Equine Surgery and Lameness 2
A 7-year-old Warmblood gelding presents with acute onset right forelimb lameness and a positive flexion test of the distal limb.
Nerve blocks reveal pain originating from the palmar digital nerves.
Radiographs show pedal osteitis.
Which treatment is most appropriate for long-term management?