22.5.4: Neurological conditions of ruminants - peripheral nervous system

Question 1

What is another name for spastic paresis?

Answer 1

Elso heel

Question 2

Answer 2

Spastic paresis

Question 3

Which animals are affected by spastic paresis and what are the clinical signs?

Answer 3

• Calves of most breeds can be affected. Not very common but some farms see many cases.
• Calves are a few weeks to 6 months old

Clinical signs:
* Very straight hocks with excess tone in gastrocnemius
* Tin soldier gait
* Usually one leg is worse than the other
* In Belgian Blue calves, the quadriceps femoris is affected and the disease is usually bilateral

Question 4

Treatment and prognosis for spastic paresis

Answer 4

• Lameness becomes progressive until the calf is recumbent -> usually euthanised
• Treatment: partial tibial neurectomy

Question 5

Obturator nerve injury clinical signs

Answer 5

• Large calves/hip-locked calves at calving
• Resulting hindlimb adductor muscle paralysis
• May be caused by direct trauma or localised ischaemia secondary to pressure from the calf

Question 6

Obturator nerve injury treatment and prognosis

Answer 6

• Conservative management: NSAIDs, deep bed, shackles/hobbles to maintain positioning of hindlimbs
• Prognosis is good in most cases but recovery can take several months
• If there is tearing/transection of the nerve, this has a poor prognosis

Question 7

Answer 7

Sciatic nerve injury
(dropped hock with knucled fetlock; leg position is considered diagnostic)

Question 8

Common cause of sciatic nerve injury, treatment and prognosis

Answer 8

• Common cause: calving esp in dairy cows, iatrogenic in calves and small ruminants
• Treated conservatively with NSAIDs and supportive care
• Prognosis is good; recovery takes a few days to several weeks
• Recumbency is associated with a poor prognosis

Question 9

Clinical signs of sciatic nerve injury

Answer 9

• Difficulty standing
• Dropped hock with knuckled fetlock - may be bilateral or unilateral

Question 10

Cause and clinical signs of tibial nerve injury

Answer 10

• Rare compared to sciatic nerve injury; occurs secondary to injury of the medial hindlimb in the hock region
• Dropped hock but hyper-extended fetlock
• =The cow walks on her heels

Question 11

Cause of femoral nerve injury

Answer 11

• Calves are injured during birth -> associated with excessive traction especially if hip-locked

Question 12

Clinical signs of femoral nerve injury

Answer 12

• Calves are unable to extend stifle or bear weight on the affected limb
• Bilaterally affected calves “dog sit”
• Quadriceps femoris atrophies over 10 days
• Patellar laxity also develops

Question 13

Treatment of femoral nerve injury

Answer 13

• Conservative
• Remember to ensure adequate nutrition

Question 14

Prognosis for femoral nerve injury

Answer 14

• Depends on severity of clinical signs
• Severely affected animals will struggle to stand without dropping on back legs
• Will struggle to drink
• If very severely affected prognosis is poor

Question 15

Common causes of brachial plexus injury

Answer 15

• Calves - injury during birth, especially due to excessive traction on forelimbs/cow going down with calf halfway delivered
• Sheep - accidents e.g. stuck in fence/gate or harness injuries in rams

Question 16

Clinical signs of brachial plexus injury

Answer 16

Inability to extend elbow, carpus or fetlock
* Dropped elbow, scuffed hoof, knuckled foot when resting
* Unable to bear weight on affected limb in severe cases
* Shoulder muscles atrophy (nervous atrophy) leaving the spine of scapular prominent

Question 17

Answer 17

Brachial plexus injury

Question 18

Treatment of brachial plexus injury

Answer 18

• Conservative
• Can splint forelimbs to aid movement and prevent tendon contracture

Question 19

Cause and clinical signs of radial nerve injury

Answer 19

• Occurs following prolonged lateral recumbency or traumatic injuries
• There is knuckling of the carpus and fetlock but the animal can still weightbear
• There is decreased sensation in the antebrachium, metacarpus and foot

Question 20

Treatment and prognosis of radial nerve injury

Answer 20

• Treatment is conservative
• Prognosis depends on severity of injury