Lameness Flashcards
impact of cattle lameness
welfare
productivity
sustainability
signs of lameness - cattle
head bobbing
short stride length
joint position - swing legs out to keep joints straight
uneven stride cadence
arched back
misshapen dew claw
90% rule
90% cattle lameness is in the feet
90% of those are hind feet
90% of those are lateral back claw
digital fat pad
cushion - shock absorption
local anti-inflammatory mediator
dutch 5 step method
- toe length
- match claws - start medial hind, and later fore
- model
- create height
- investigate/trim loose claw
1-3 in healthy cows
4-5 therapeutic
white line disease - cattle
white line- comparatively soft
can travel up coronary band
risk factors - surfaces, horn integrity, stockmanship
treatment - block other claw, remove loose horn, NSAIDs
prevention - good surfaces, good stockmanship, appropriate nutrition
sole ulcers
develop over period of weeks
grow from inside out
disruption of horn growth due to point pressure on corium - interrupts blood supply
risk factors - foot trimming, standing time and surfaces, fat mobilisation from digital fat pad (transition from pregnancy to lactation), inflammation
standing times most important factors
should lie down for 14 hours
surfaces - changes distribution of weight on foot
concrete increased caudal lateral weight
treatment - modelling in foot trimming, block
prevention - increased cow comfort (minimised standing times), maximised transitional health, ensure not lame in dry yards, prompt id and treatment, foot trimming technique and strategy
metabolic impact on lameness - cattle
fat mobilisation in early lactation
fat mobilised –> thinning digital cushion –> poor shock absorption
fat pad also releases inflammatory mediators - cause more thinning
lame cow also eats less –> BCS down even more
digital dermatitis - cattle
multifactorial causes - genetic susceptibility, bacterial, hoof hygiene
risk factors - standing in shit, prior infection (may be chronic)
cycle of infection - active lesion time, healing, chronic, chronic/dormant, non-infected (probably doesn’t often happen)
treatment - if red and hot (Acute, active) then topical treatment, if keratinised (chronic, inactive) then foot bath
prevention - hygiene in cow sheds, increased surface area, control in heifers
foul in the foot/foot rot - cattle
bacterial infection
painful, swollen
bad smell
needs skin challenge by some physical trauma to allow bacteria to enter
treatment - NSAIDs, systemic antimicrobials, local treatments
prevention - hygiene, minimise risk of interdigital trauma
other less common lameness causes - cattle
heel horn erosion
interdigital hyperplasia
toe lesions
fissures
corkscrew claws
deep digital sepsis
upper lameness differentials - cattle
foot and mouth
malignant catarrhal fever
polyarthritis - mycoplasma, joint ill
trauma
iatrogenic - eg from trimming wrong
nutritional
presentation of pain elsewhere - abdominal or respiratory affecting posture
herd level management - cattle lameness
breeding - conformation, immune factors
mobility scoring
trimming
foot bathing - 3-4x per week, not too acidic, no more than 200 cows per bath
hoof health assessment
comfort and hygiene scoring
first aid protocols
mobility scoring - cattle
0 - great mobility - even weight bearing, long fluid strides
1 - imperfect mobility - uneven steps or short strides
2 - impaired mobility - uneven weight bearing on a limb and shortened strides, immediately identifiable
3 - severely impaired mobility - slower than brisk human pace, lame leg easily identifiable, back arched
hygiene scoring - cattle
0 - clean - no dirt or only minor splashing
1 - dirty - area of dirtiness at least palm size
2 - very dirty - area of dirtiness at least forearm length
factors affecting cleanliness - cattle
cubicle cleanliness
cubicle comfort
amount and type of bedding
manure consistency and herd health
frequency of alley cleaning, scraping, collecting yard
space allowance per cow
hair on udder
sub-solar abscess - horse
most common cause of acute lameness
ascending bacterial infection in chorium
grey-black fluid
risk factors - penetration injury, poor foot confirmation, seedy toe, wet muddy conditions, chronic laminitis, PPID
diagnosis - acute unilateral lameness, bounding pulses, heat in hoof, marked pain response to hoof testers
treatment - encourage drainage, don’t use nerve block, poultice, pain relief, tetanus prophylaxis
don’t use antimicrobials unless purulent
chronic abscess - horse
rupture at coronary band or heel bulb
encourage distal drainage
may need repeat flushing
purulent abscess - horse
deeper/more sensitive structures involved
radiograph to diagnose
may need more extensive surgery
antimicrobials
solar penetrations - horse
leave in penetrating object
support leg with bandage/splint
radiograph with object in
may be delay in lameness after removed
sequelae - pedal bone damage, soft tissue damage, synovial infection
broad spectrum antimicrobials, NSAIDs and tetanus prophylaxis
hoof trauma - horse
foot cast for support, sterility and pain relief
fractures/hairline fracture - horse
management - stabilise, analgesia, situational awareness, prioritise welfare, potentially euthanasia
pedal bone fracture - can heal
can maybe use plates or surgery
hairline fractures - subtle on radiographs but can be painful and lead to non weight bearing lameness - if too much pain relief horse may make it worse
palmar digital nerve block
blocks- sole, navicular apparatus, soft tissue of heel, coffin joint, distal DDFT, distal sesamoidean ligament
put in at proximal edge of cartilage of foot, both sides, palmar aspect
2/3 inch needle (25 gauge)
2.5 ml mepivicaine
abaxial sesamoid nerve block
blocks - foot, middle phalanx, PIPJ, distopalmar aspects of proximal phalanx, distal SDFT and DDFT, distal sesamoidean ligaments, distal annular ligament, fetlock
either side back of fetlock
2/3 inch needle (25 gauge)
2.5 ml mepivicaine
coffin joint nerve block
blocks - coffin joint, navicular apparatus, branches of palmar digital nerves, tor region of sole
does basically same job as palmar digital
dorsal aspect of foot just above coronary band in the middle
trot up quickly after - otherwise spreads to palmar digital pouch nerves
1.5 inch needle (20 gauge)
5-6 ml mepivicaine
navicular bursa nerve block
blocks - navicular bursa, navicular bone and associated ligaments, solar toe pain, distal DDFT, does not block coffin joint
used to see if pain is navicular or from coffin joint
trot up after about 10 mins
difficult to do without sedating horse - tough skin - back of heel pointing downwards towards hoof
20 gauge spinal needle
digital flexor tendon sheath nerve block
blocks - lesions in DFTS and the portion of DDFT distal to sheath
to work out if issue is with the DDFT
1-1.5 inch needle (20 gauge)
use tourniquet, encourages fluid in DFTS to move distal
nerve block limitations
proximal diffusion
horse may just have warmed out of lameness
general interpretation errors
anaesthetic in wrong place - fascia or synovial structure or blood vessel
mechanical lameness that doesn’t respond to anaesthesia
may only desensitise skin
diagnostic imaging - horse lameness
prepare foot and foot balance image first
radiograph
- lateromedial - dorso-palmar imbalance
- dorsopalmar - shows it foot not aligned with fetlock
- dorso proximal palmarodistal oblique - cyst like lesions, distal border fragment, lucent zones and medullary sclerosis of navicular bone, fractures, keratomas, or osteitis of pedal bone
- navicular skyline - navicular bone
stationary foot observation - horse
90% forelimb lameness is in foot
size/shape
hoof pastern angle
coronary band conformation
shoe - type, wear, pattern, position
foot palpation - horse
coronary band
coffin joint
lateral cartilages
heel bulbs
gait assessment - horse
firm, flat, non-slip surface
straight line
flexion tests
soft and hard lunge
may need to be ridden
flexion test - horse
apply stress to region of the limb for set time period then trot off again to see effect on gait
aim to increase potential lameness to make it easier to see
may still respond even if don’t have lameness originally
msk evaluation - small animal
palpation - swelling, discomfort, muscle asymmetry, wounds
manipulation
gait examination - walk and trot, straight line and turning
Scald/Ovine Indigital Dermatitis - Sheep
wet conditions
fusebacterium necrophorum
mild and transient lameness
no horn involvement
associated with foot rot
foot rot - sheep
90% of lameness
dichelobacter nodusus - but needs fusebacterium necrophorum to facilitate skin invasion
requires devitalised skin
severe lameness
often recumbent - reduced feeding time
moist, red, swollen skin between claws
separation of hoof wall
usually affects multiple feet
can lead to fly strike
Contagious Ovine Digital Dermatitis - Sheep
CODD
treponeme spp.
linked to foot rot
severe lameness
usually one claw of one foot
ulcers at coronary band with under run hoof
can lead to whole foot avulsion
graded - 1-5
NSAIDs and antibiotics
white line separation - sheep
often individuals rather than whole flock
multiple causes - stony ground, nutritional
“shelley hoof”
separation of hoof wall from underlying tissues
can lead to abscess
toe granuloma - sheep
painful red swellings
caused by over trimming, chemical irritation, or chronic untreated lesions
