22.5.2: Less common causes of lameness

Question 1

Answer 1

Sole haemorrhage/bruising

Question 2

Answer 2

Foreign body penetration

Question 3

Answer 3

Heel horn erosion (Slurry heel)

Question 4

Answer 4

Vertical fissure (a.k.a. sand crack) with granuloma above

Question 5

Answer 5

(Mild) Horizontal fissures (Hardship lines)

Question 6

Answer 6

More severe horizontal fissures (hardship lines) resulting in the formation of thimbles

Question 7

Comment on this cow’s stance

Answer 7

Classic cross-legged stance adopted by a cow with a fractured phalanx (medial claw, right foreleg)

Question 8

Answer 8

Interdigital skin hyperplasia (a.k.a. interdigital corns/growth/fibromas/granulomas)

Question 9

Describe the aetiology of slurry heel

Answer 9

• The result of standing in wet corrosive slurry during the winter housing period leads to the soft horn of the heel becoming eroded
• Pits and fissures form in the heel
• If severe, or left untreated, the heel eventually disappears completely

Question 10

Treatment of slurry heel

Answer 10

• Regular formalin foot baths through the winter will harden the feet and limit the effects of heel erosion
• Gently trim away loose and fissured horn to remove pocket but spare healthy heel as excessive trimming will exacerbate the problem
• Corrective trimming aims to increase the angle of the front wall to the ground to reduce the pressure on the ulcer site

Question 11

Prognosis for slurry heel

Answer 11

• Good if treated before the disease has completely destroyed the heel
• If this has been allowed to happen, the foot rotates backwards
• The front wall of the hoof meets the ground at a shallower angle -> leads to overgrowth of the hoof at the toe
• Meanwhile pressure exerted by pedal bone pinches the corium and can lead to development of sole haemorrhage and eventually sole ulcers

Question 12

Prevention of slurry heel

Answer 12

• Improve underfoot conditions during the winter period will decrease the severity of the condition
• Certain amount of heel erosion is almost inevitable in housed cattle
• Routine formalin foot baths will often limit the severity of disease

Question 13

Aetiology of vertical fissures (sand cracks)

Answer 13

• Damage to the periople (produces waxy layer that prevents horn drying out) or the underlying corium (produces wall of horn) causes vertical cracks
• Digital damage lesions/trauma/hot dry sandy conditions can cause this

Question 14

Treatment of vertical fissures (sand cracks)

Answer 14

• Open the crack up and exposed underlying abscesses to allow them to drain
• If the crack is opened and there is movement between the two wall sections, granulation tissue can develop and protrude through -> in these cases, resect granulation tissue and apply block to sound claw to limit sheering forces

Question 15

Prognosis for vertical fissures

Answer 15

• Generally good although some can be quite difficult to treat and require multiple trims before the wall returns to normal
• If periople has been permanently damaged leading to long-term continual production of defective wall, prognosis is poor

Question 16

Aetiology of horizontal fissures (hardship lines)

Answer 16

• The production of wall horn is interrupted as it is being produced at the coronary band
• Any severe toxic condition (mastitis, metritis, acute acidosis) can result in temporary but complete absence of horn production
• When horn production restarts, there will be a complete circumferential fissure often round all 8 claws

Question 17

Clinical signs of horizontal fissures (hardship lines)

Answer 17

• Often asymptomatic unless the fissure and underlying laminae become infected or the pinching forces result in the production of a granuloma
• May show clinical signs when fissure has grown down the wall and led to the formation of fissures -> lameness, infection, granulomas are seen

Question 18

Treatment of horizontal fissures (hardship lines)

Answer 18

• If infection has been established, crack should be opened and underlying abscesses allowed to drain
• Any granulation tissue should be resected
• Often difficult/pointless to block the other claw as very often all claws are affected

Question 19

Prognosis for horizontal fissures (hardship lines)

Answer 19

• Prognosis varies according to disease severity
• Sometimes thimbles grow out and are shed asymptomatically
• If all claws are seriously affected, it may be necessary to cull the affected animal

Question 20

True/false: if disruption of horn production is not complete, thinning of the wall occurs. These thinner edges develop into ridges (hardship lines) as the wall grows.

Answer 20

True

Question 21

Aetiology of distal phalanx fractures

Answer 21

• Medial claw of front feet - trauma during bulling (slipping off cows whilst mounting)
• Hind feet - slipping in parlour
• Herd “outbreaks” have been associated with fluoride poisoning

Question 22

Clinical signs of distal phalanx fractures

Answer 22

• Acute onset lameness with no other obvious clinical signs
• If the medial claw of the front feet is affected, animals will often stand “cross-legged” so as to take the weight on the unaffected lateral claw

Question 23

Treatment of distal phalanx fractures

Answer 23

• Distal phalanx is splinted well by the hoof capsule
• Apply a block to the unaffected claw
• (I can’t help but think some NSAIDs might be in order too?!)

Question 24

Prognosis for distal phalanx fractures

Answer 24

• Good providing no other complicating factors e.g. fluoride poisoning

Question 25

Aetiology of interdigital skin hyperplasia

Answer 25

• Chronic irritation of the interdigital area e.g. chronic infection, impaction of small stones/dirt
• Foul in the foot may predispose to the condition later in life
• Hereditary component has been postulated but remains unproven

Question 26

Clinical signs of interdigital skin hyperplasia

Answer 26

• Often asymptomatic; incidental finding during foot trimming
• Causes lameness is overgrowth of skin becomes infected (foul, DD) or becomes so large that it is pinched between the claws during locomotion

Question 27

Treatment of interdigital skin hyperplasia

Answer 27

• If hyperplastic area is infected -> treat infection, this will often resolve the lameness
• In cases where pinching is mild, “dishing” out the horn from the interdigital area will often alleviate clinical signs
• In severe cases/where corrective trimming, surgically remove the hyperplastic skin under local or intravenous regional anaesthesia

Question 28

Prognosis for interdigital skin hyperplasia

Answer 28

Good

Question 29

Prevention of interdigital skin hyperplasia

Answer 29

• Ensure underfoot conditions are optimal during winter housing period

Question 30

Aetiology of suprascapular paralysis

Answer 30

• C6 and C7 outflow provides motor innervation to supraspinatus and infraspinatus muscles
• Usually damaged by trama to prescapular or scapular area

Question 31

Clinical signs of suprascapular paralysis

Answer 31

• Limb can be advanced, but abducts when weight bearing
• Stride may be shortened
• Atrophy of supraspinatus and infraspinatus muscles can be partial or almost complete

Question 32

Answer 32

Radial paralysis in left foreleg

Question 33

Answer 33

Radial paralysis of left forelimb

Question 34

Answer 34

Radial nerve paralysis
In more extreme presentations, where the dorsum of the pastern is in contact with the ground, then paralysis of the whole brachial plexus should be considered.

Question 35

Answer 35

Radial nerve paralysis

Question 36

Aetiology of radial paralysis

Answer 36

• C7, C8 ?? and T1 outflow provide motor innervation of carpus and digit extensors and sensation to lateral side of limb
• Excessive traction on limb (e.g. during calving), trauma to scapulohumeral area, and recumbency can damage the nerve

Question 37

Clinical signs of radial paralysis

Answer 37

• Damage to the nerve proximally leads to the wall being held in flexion with the elbow dropped
• The cranial wall of the hoof “scuffs” the floor during locomotion
• If the nerve is damaged distally, innervation of the elbow is often normal but the carpus and fetlock are held in flexion

Question 38

Aetiology of brachial plexus paralysis

Answer 38

• C5 to T2 outflow make up the principal nerves innervating the forelimb (radial, median and ulnar)
• Excessive traction on the limb (e.g. during calving), traumatic abduction and prolonged lateral recumbency can all damage the brachial plexus